| 1. |
- Barber, Megan R.W., et al.
(author)
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Economic Evaluation of Damage Accrual in an International Systemic Lupus Erythematosus Inception Cohort Using a Multistate Model Approach
- 2020
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In: Arthritis Care and Research. - : Wiley. - 2151-464X .- 2151-4658. ; 72:12, s. 1800-1808
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Journal article (peer-reviewed)abstract
- Objective: There is a paucity of data regarding health care costs associated with damage accrual in systemic lupus erythematosus. The present study was undertaken to describe costs associated with damage states across the disease course using multistate modeling. Methods: Patients from 33 centers in 11 countries were enrolled in the Systemic Lupus International Collaborating Clinics (SLICC) inception cohort within 15 months of diagnosis. Annual data on demographics, disease activity, damage (SLICC/American College of Rheumatology Damage Index [SDI]), hospitalizations, medications, dialysis, and selected procedures were collected. Ten-year cumulative costs (Canadian dollars) were estimated by multiplying annual costs associated with each SDI state by the expected state duration using a multistate model. Results: A total of 1,687 patients participated; 88.7% were female, 49.0% were white, mean ± SD age at diagnosis was 34.6 ± 13.3 years, and mean time to follow-up was 8.9 years (range 0.6–18.5 years). Mean annual costs were higher for those with higher SDI scores as follows: $22,006 (Canadian) (95% confidence interval [95% CI] $16,662, $27,350) for SDI scores ≥5 versus $1,833 (95% CI $1,134, $2,532) for SDI scores of 0. Similarly, 10-year cumulative costs were higher for those with higher SDI scores at the beginning of the 10-year interval as follows: $189,073 (Canadian) (95% CI $142,318, $235,827) for SDI scores ≥5 versus $21,713 (95% CI $13,639, $29,788) for SDI scores of 0. Conclusion: Patients with the highest SDI scores incur 10-year cumulative costs that are ~9-fold higher than those with the lowest SDI scores. By estimating the damage trajectory and incorporating annual costs, data on damage can be used to estimate future costs, which is critical knowledge for evaluating the cost-effectiveness of novel therapies.
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| 2. |
- Hanly, John G., et al.
(author)
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A Longitudinal Analysis of Outcomes of Lupus Nephritis in an International Inception Cohort Using a Multistate Model Approach
- 2016
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In: Arthritis & Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 68:8, s. 1932-1944
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Journal article (peer-reviewed)abstract
- Objective: To study bidirectional change and predictors of change in estimated glomerular filtration rate (GFR) and proteinuria in lupus nephritis (LN) using a multistate modeling approach. Methods: Patients in the Systemic Lupus International Collaborating Clinics inception cohort were classified annually into estimated GFR state 1 (>60 ml/minute), state 2 (30–60 ml/minute), or state 3 (3.0 gm/day), or end-stage renal disease (ESRD) or death. Using multistate modeling, relative transition rates between states indicated improvement and deterioration. Results: Of 1,826 lupus patients, 700 (38.3%) developed LN. During a mean ± SD follow-up of 5.2 ± 3.5 years, the likelihood of improvement in estimated GFR and estimated proteinuria was greater than the likelihood of deterioration. After 5 years, 62% of patients initially in estimated GFR state 3 and 11% of patients initially in estimated proteinuria state 3 transitioned to ESRD. The probability of remaining in the initial states 1, 2, and 3 was 85%, 11%, and 3%, respectively, for estimated GFR and 62%, 29%, and 4%, respectively, for estimated proteinuria. Male sex predicted improvement in estimated GFR states; older age, race/ethnicity, higher estimated proteinuria state, and higher renal biopsy chronicity scores predicted deterioration. For estimated proteinuria, race/ethnicity, earlier calendar years, damage scores without renal variables, and higher renal biopsy chronicity scores predicted deterioration; male sex, presence of lupus anticoagulant, class V nephritis, and mycophenolic acid use predicted less improvement. Conclusion: In LN, the expected improvement or deterioration in renal outcomes can be estimated by multistate modeling and is preceded by identifiable risk factors. New therapeutic interventions for LN should meet or exceed these expectations.
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| 3. |
- Hanly, John G., et al.
(author)
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Cerebrovascular Events in Systemic Lupus Erythematosus : Results From an International Inception Cohort Study
- 2018
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In: Arthritis Care and Research. - : Wiley. - 2151-464X .- 2151-4658. ; 70:10, s. 1478-1487
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Journal article (peer-reviewed)abstract
- Objective: To determine the frequency, characteristics, and outcomes of cerebrovascular events (CerVEs), as well as clinical and autoantibody associations in a multiethnic/racial inception cohort of patients with systemic lupus erythematosus (SLE). Methods: A total of 1,826 patients were assessed annually for 19 neuropsychiatric (NP) events, including 5 types of CerVEs: 1) stroke, 2) transient ischemia, 3) chronic multifocal ischemia, 4) subarachnoid/intracranial hemorrhage, and 5) sinus thrombosis. Global disease activity (Systemic Lupus Erythematosus Disease [SLE] Activity Index 2000), damage scores (SLE International Collaborating Clinics/American College of Rheumatology Damage Index), and Short Form 36 (SF-36) scores were collected. Time to event, linear and logistic regressions, and multistate models were used as appropriate. Results: CerVEs were the fourth most frequent NP event: 82 of 1,826 patients had 109 events; of these events, 103 were attributed to SLE, and 44 were identified at the time of enrollment. The predominant events were stroke (60 of 109 patients) and transient ischemia (28 of 109 patients). CerVEs were associated with other NP events attributed to SLE, non–SLE-attributed NP events, African ancestry (at US SLICC sites), and increased organ damage scores. Lupus anticoagulant increased the risk of first stroke and sinus thrombosis and transient ischemic attack. Physician assessment indicated resolution or improvement in the majority of patients, but patients reported sustained reduction in SF-36 summary and subscale scores following a CerVE. Conclusion: CerVEs, the fourth most frequent NP event in SLE, are usually attributable to lupus. In contrast to good physician-reported outcomes, patients reported a sustained reduction in health-related quality of life following a CerVE.
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| 4. |
- Hanly, John G., et al.
(author)
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Mood Disorders in Systemic Lupus Erythematosus: Results From an International Inception Cohort Study
- 2015
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In: Arthritis & Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 67:7, s. 1837-1847
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Journal article (peer-reviewed)abstract
- ObjectiveTo examine the frequency, characteristics, and outcome of mood disorders, as well as clinical and autoantibody associations, in a multiethnic/racial, prospective inception cohort of patients with systemic lupus erythematosus (SLE). MethodsPatients were assessed annually for mood disorders (4 types, according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) and 18 other neuropsychiatric events. Global disease activity scores (SLE Disease Activity Index 2000 [SLEDAI-2K]), damage scores (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index [SDI]), and Short Form 36 subscales, mental and physical component summary scores were collected. Time to event, linear and ordinal regressions, and multi-state models were used as appropriate. ResultsAmong the 1,827 patients with SLE, 88.9% were female, and 48.9% were Caucasian. The mean SD age of the patients was 35.1 +/- 13.3 years, disease duration was 5.6 +/- 4.8 months, and the length of followup was 4.7 +/- 3.5 years. During the course of the study, 863 (47.2%) of the 1,827 patients had 1,627 neuropsychiatric events. Mood disorders occurred in 232 (12.7%) of 1,827 patients, and 98 (38.3%) of 256 mood disorder events were attributed to SLE. The estimated cumulative incidence of any mood disorder after 10 years was 17.7% (95% confidence interval 15.1, 20.2%). A greater risk of mood disorder was associated with concurrent neuropsychiatric events (P0.01), and a lower risk was associated with Asian race/ethnicity (P=0.01) and treatment with immunosuppressive drugs (P=0.003). Mood disorders were associated with lower mental health and mental component summary scores but not with the SLEDAI-2K, SDI, or lupus autoantibodies. Among the 232 patients with depression, 168 (72.4%) were treated with antidepressants. One hundred twenty-six (49.2%) of 256 mood disorders resolved in 117 (50.4%) of 232 patients. ConclusionMood disorders, the second most frequent neuropsychiatric event in patients with SLE, have a negative impact on health-related quality of life and improve over time. The lack of association with global SLE disease activity, cumulative organ damage, and lupus autoantibodies emphasizes the multifactorial etiology of mood disorders and a role for non-lupus-specific therapies.
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| 5. |
- Hanly, John G., et al.
(author)
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Peripheral Nervous System Disease in Systemic Lupus Erythematosus : Results From an International Inception Cohort Study
- 2020
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In: Arthritis and Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 72:1, s. 67-77
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Journal article (peer-reviewed)abstract
- Objective: To determine the frequency, clinical characteristics, associations, and outcomes of different types of peripheral nervous system (PNS) disease in a multiethnic/multiracial, prospective inception cohort of systemic lupus erythematosus (SLE) patients. Methods: Patients were evaluated annually for 19 neuropsychiatric (NP) events including 7 types of PNS disease. SLE disease activity, organ damage, autoantibodies, and patient and physician assessment of outcome were measured. Time to event and linear regressions were used as appropriate. Results: Of 1,827 SLE patients, 88.8% were female, and 48.8% were white. The mean ± SD age was 35.1 ± 13.3 years, disease duration at enrollment was 5.6 ± 4.2 months, and follow-up was 7.6 ± 4.6 years. There were 161 PNS events in 139 (7.6%) of 1,827 patients. The predominant events were peripheral neuropathy (66 of 161 [41.0%]), mononeuropathy (44 of 161 [27.3%]), and cranial neuropathy (39 of 161 [24.2%]), and the majority were attributed to SLE. Multivariate Cox regressions suggested longer time to resolution in patients with a history of neuropathy, older age at SLE diagnosis, higher SLE Disease Activity Index 2000 scores, and for peripheral neuropathy versus other neuropathies. Neuropathy was associated with significantly lower Short Form 36 (SF-36) physical and mental component summary scores versus no NP events. According to physician assessment, the majority of neuropathies resolved or improved over time, which was associated with improvements in SF-36 summary scores for peripheral neuropathy and mononeuropathy. Conclusion: PNS disease is an important component of total NPSLE and has a significant negative impact on health-related quality of life. The outcome is favorable for most patients, but our findings indicate that several factors are associated with longer time to resolution.
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| 6. |
- Hanly, John G., et al.
(author)
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Psychosis in Systemic Lupus Erythematosus : Results From an International Inception Cohort Study
- 2019
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In: Arthritis and Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 71:2, s. 281-289
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Journal article (peer-reviewed)abstract
- Objective: To determine, in a large, multiethnic/multiracial, prospective inception cohort of patients with systemic lupus erythematosus (SLE), the frequency, attribution, clinical, and autoantibody associations with lupus psychosis and the short- and long-term outcomes as assessed by physicians and patients. Methods: Patients were evaluated annually for 19 neuropsychiatric (NP) events including psychosis. Scores on the Systemic Lupus Erythematosus Disease Activity Index 2000, the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index, and the Short Form 36 (SF-36) were recorded. Time to event and linear regressions were used as appropriate. Results: Of 1,826 SLE patients, 88.8% were female and 48.8% were Caucasian. The mean ± SD age was 35.1 ± 13.3 years, the mean ± SD disease duration was 5.6 ± 4.2 months, and the mean ± SD follow-up period was 7.4 ± 4.5 years. There were 31 psychotic events in 28 of 1,826 patients (1.53%), and most patients had a single event (26 of 28 [93%]). In the majority of patients (20 of 25 [80%]) and events (28 of 31 [90%]), psychosis was attributed to SLE, usually either in the year prior to or within 3 years of SLE diagnosis. Positive associations (hazard ratios [HRs] and 95% confidence intervals [95% CIs]) with lupus psychosis were previous SLE NP events (HR 3.59 [95% CI 1.16–11.14]), male sex (HR 3.0 [95% CI 1.20–7.50]), younger age at SLE diagnosis (per 10 years) (HR 1.45 [95% CI 1.01–2.07]), and African ancestry (HR 4.59 [95% CI 1.79–11.76]). By physician assessment, most psychotic events resolved by the second annual visit following onset, in parallel with an improvement in patient-reported SF-36 summary and subscale scores. Conclusion: Psychosis is an infrequent manifestation of NPSLE. Generally, it occurs early after SLE onset and has a significant negative impact on health status. As determined by patient and physician report, the short- and long-term outlooks are good for most patients, although careful follow-up is required.
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| 7. |
- Hanly, John G., et al.
(author)
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Seizure disorders in systemic lupus erythematosus results from an international, prospective, inception cohort study
- 2012
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In: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 71:9, s. 1502-1509
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Journal article (peer-reviewed)abstract
- Objective The aim of this study was to describe the frequency, attribution, outcome and predictors of seizures in systemic lupus erythematosus (SLE). Methods The Systemic Lupus International Collaborating Clinics, or SLICC, performed a prospective inception cohort study. Demographic variables, global SLE disease activity (SLE Disease Activity Index 2000), cumulative organ damage (SLICC/American College of Rheumatology Damage Index (SDI)) and neuropsychiatric events were recorded at enrolment and annually. Lupus anticoagulant, anticardiolipin, anti-beta(2) glycoprotein-I, antiribosomal P and anti-NR2 glutamate receptor antibodies were measured at enrolment. Physician outcomes of seizures were recorded. Patient outcomes were derived from the SF-36 (36-Item Short Form Health Survey) mental component summary and physical component summary scores. Statistical analyses included Cox and linear regressions. Results The cohort was 89.4% female with a mean follow-up of 3.5 +/- 2.9 years. Of 1631 patients, 75 (4.6%) had >= 1 seizure, the majority around the time of SLE diagnosis. Multivariate analysis indicated a higher risk of seizures with African race/ethnicity (HR (CI): 1.97 (1.07 to 3.63); p=0.03) and lower education status (1.97 (1.21 to 3.19); p<0.01). Higher damage scores (without neuropsychiatric variables) were associated with an increased risk of subsequent seizures (SDI=1:3.93 (1.46 to 10.55); SDI=2 or 3:1.57 (0.32 to 7.65); SDI >= 4:7.86 (0.89 to 69.06); p=0.03). There was an association with disease activity but not with autoantibodies. Seizures attributed to SLE frequently resolved (59/78 (76%)) in the absence of antiseizure drugs. There was no significant impact on the mental component summary or physical component summary scores. Antimalarial drugs in the absence of immunosuppressive agents were associated with reduced seizure risk (0.07 (0.01 to 0.66); p=0.03). Conclusion Seizures occurred close to SLE diagnosis, in patients with African race/ethnicity, lower educational status and cumulative organ damage. Most seizures resolved without a negative impact on health-related quality of life. Antimalarial drugs were associated with a protective effect.
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| 8. |
- Urowitz, Murray B., et al.
(author)
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Accrual of Atherosclerotic Vascular Events in a Multicenter Inception Systemic Lupus Erythematosus Cohort
- 2020
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In: Arthritis and Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 72:10, s. 1734-1740
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Journal article (peer-reviewed)abstract
- Objective: In previous studies, atherosclerotic vascular events (AVEs) were shown to occur in ~10% of patients with systemic lupus erythematosus (SLE). We undertook this study to investigate the annual occurrence and potential risk factors for AVEs in a multinational, multiethnic inception cohort of patients with SLE. Methods: A large 33-center cohort of SLE patients was followed up yearly between 1999 and 2017. AVEs were attributed to atherosclerosis based on SLE being inactive at the time of the AVE as well as typical atherosclerotic changes observed on imaging or pathology reports and/or evidence of atherosclerosis elsewhere. Analyses included descriptive statistics, rate of AVEs per 1,000 patient-years, and univariable and multivariable relative risk regression models. Results: Of the 1,848 patients enrolled in the cohort, 1,710 had ≥1 follow-up visit after enrollment, for a total of 13,666 patient-years. Of these 1,710 patients, 3.6% had ≥1 AVEs attributed to atherosclerosis, for an event rate of 4.6 per 1,000 patient-years. In multivariable analyses, lower AVE rates were associated with antimalarial treatment (hazard ratio [HR] 0.54 [95% confidence interval (95% CI) 0.32–0.91]), while higher AVE rates were associated with any prior vascular event (HR 4.00 [95% CI 1.55–10.30]) and a body mass index of >40 kg/m2 (HR 2.74 [95% CI 1.04–7.18]). A prior AVE increased the risk of subsequent AVEs (HR 5.42 [95% CI 3.17–9.27], P < 0.001). Conclusion: The prevalence of AVEs and the rate of AVE accrual demonstrated in the present study is much lower than that seen in previously published data. This may be related to better control of both the disease activity and classic risk factors.
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| 9. |
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| 10. |
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| 11. |
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| 12. |
- Hanly, J. G., et al.
(author)
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Autoantibodies as biomarkers for the prediction of neuropsychiatric events in systemic lupus erythematosus
- 2011
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In: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 70:10, s. 1726-1732
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Journal article (peer-reviewed)abstract
- Objective Neuropsychiatric events occur unpredictably in systemic lupus erythematosus (SLE) and most biomarker associations remain to be prospectively validated. This study examined a disease inception cohort of 1047 SLE patients to determine which autoantibodies at enrolment predicted subsequent neuropsychiatric events. Methods Patients with a recent SLE diagnosis were assessed prospectively for up to 10 years for neuropsychiatric events using the American College of Rheumatology case definitions. Decision rules of graded stringency determined whether neuropsychiatric events were attributable to SLE. Associations between the first neuropsychiatric event and baseline autoantibodies (lupus anticoagulant (LA), anticardiolipin, anti-beta(2) glycoprotein-I, anti-ribosomal P and anti-NR2 glutamate receptor) were tested by Cox proportional hazards regression. Results Disease duration at enrolment was 5.4 +/- 4.2 months, follow-up was 3.6 +/- 2.6 years. Patients were 89.1% female with mean (+/- SD) age 35.2 +/- 13.7 years. 495/1047 (47.3%) developed one or more neuropsychiatric event (total 917 events). Neuropsychiatric events attributed to SLE were 15.4% (model A) and 28.2% (model B). At enrolment 21.9% of patients had LA, 13.4% anticardiolipin, 15.1% anti-beta(2) glycoprotein-I, 9.2% anti-ribosomal P and 13.7% anti-NR2 antibodies. LA at baseline was associated with subsequent intracranial thrombosis (total n=22) attributed to SLE (model B) (HR 2.54, 95% CI 1.08 to 5.94). Anti-ribosomal P antibody was associated with subsequent psychosis (total n=14) attributed to SLE (model B) (HR 3.92, 95% CI 1.23 to 12.5, p=0.02). Other autoantibodies did not predict neuropsychiatric events. Conclusion In a prospective study of 1047 recently diagnosed SLE patients, LA and anti-ribosomal P antibodies are associated with an increased future risk of intracranial thrombosis and lupus psychosis, respectively.
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| 13. |
- Hanly, John G., et al.
(author)
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Headache in Systemic Lupus Erythematosus Results From a Prospective, International Inception Cohort Study
- 2013
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In: Arthritis and Rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 65:11, s. 2887-2897
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Journal article (peer-reviewed)abstract
- ObjectiveTo examine the frequency and characteristics of headaches and their association with global disease activity and health-related quality of life (HRQOL) in patients with systemic lupus erythematosus (SLE). MethodsA disease inception cohort was assessed annually for headache (5 types) and 18 other neuropsychiatric (NP) events. Global disease activity scores (SLE Disease Activity Index 2000 [SLEDAI-2K]), damage scores (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index [SDI]), and Short Form 36 (SF-36) mental and physical component summary scores were collected. Time to first headache and associations with SF-36 scores were analyzed using Cox proportional hazards and linear regression models with generalized estimating equations. ResultsAmong the 1,732 SLE patients enrolled, 89.3% were female and 48.3% were white. The mean SD age was 34.6 +/- 13.4 years, duration of disease was 5.6 +/- 5.2 months, and length of followup was 3.8 +/- 3.1 years. At enrollment, 17.8% of patients had headache (migraine [60.7%], tension [38.6%], intractable nonspecific [7.1%], cluster [2.6%], and intracranial hypertension [1.0%]). The prevalence of headache increased to 58% after 10 years. Only 1.5% of patients had lupus headache, as identified in the SLEDAI-2K. In addition, headache was associated with other NP events attributed to either SLE or non-SLE causes. There was no association of headache with SLEDAI-2K scores (without the lupus headache variable), SDI scores, use of corticosteroids, use of antimalarials, use of immunosuppressive medications, or specific autoantibodies. SF-36 mental component scores were lower in patients with headache compared with those without headache (mean +/- SD 42.5 +/- 12.2 versus 47.8 +/- 11.3; P < 0.001), and similar differences in physical component scores were seen (38.0 +/- 11.0 in those with headache versus 42.6 +/- 11.4 in those without headache; P < 0.001). In 56.1% of patients, the headaches resolved over followup. ConclusionHeadache is frequent in SLE, but overall, it is not associated with global disease activity or specific autoantibodies. Although headaches are associated with a lower HRQOL, the majority of headaches resolve over time, independent of lupus-specific therapies.
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| 14. |
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| 15. |
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| 16. |
- Hanly, JG, et al.
(author)
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SF-36 summary and subscale scores are reliable outcomes of neuropsychiatric events in systemic lupus erythematosus
- 2011
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In: Annals of the rheumatic diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 70:6, s. 961-967
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Journal article (peer-reviewed)abstract
- To examine change in health-related quality of life in association with clinical outcomes of neuropsychiatric events in systemic lupus erythematosus (SLE).MethodsAn international study evaluated newly diagnosed SLE patients for neuropsychiatric events attributed to SLE and non-SLE causes. The outcome of events was determined by a physician-completed seven-point scale and compared with patient-completed Short Form 36 (SF-36) health survey questionnaires. Statistical analysis used linear mixed-effects regression models with patient-specific random effects.Results274 patients (92% female; 68% Caucasian), from a cohort of 1400, had one or more neuropsychiatric event in which the interval between assessments was 12.3±2 months. The overall difference in change between visits in mental component summary (MCS) scores of the SF-36 was significant (p<0.0001) following adjustments for gender, ethnicity, centre and previous score. A consistent improvement in neuropsychiatric status (N=295) was associated with an increase in the mean (SD) adjusted MCS score of 3.66 (0.89) in SF-36 scores. Between paired visits when the neuropsychiatric status consistently deteriorated (N=30), the adjusted MCS score decreased by 4.00 (1.96). For the physical component summary scores the corresponding changes were +1.73 (0.71) and −0.62 (1.58) (p<0.05), respectively. Changes in SF-36 subscales were in the same direction (p<0.05; with the exception of role physical). Sensitivity analyses confirmed these findings. Adjustment for age, education, medications, SLE disease activity, organ damage, disease duration, attribution and characteristics of neuropsychiatric events did not substantially alter the results.ConclusionChanges in SF-36 summary and subscale scores, in particular those related to mental health, are strongly associated with the clinical outcome of neuropsychiatric events in SLE patients.
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| 17. |
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| 18. |
- Mergulhao, F. J. M., et al.
(author)
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Medium and copy number effects on the secretion of human proinsulin in Escherichia coli using the universal stress promoters uspA and uspB
- 2003
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In: Applied Microbiology and Biotechnology. - : Springer Science and Business Media LLC. - 0175-7598 .- 1432-0614. ; 61:06-maj, s. 495-501
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Journal article (peer-reviewed)abstract
- The use of the uspA and uspB promoters (universal stress promoters) for heterologous protein production in Escherichia coli is described. Best results were obtained with a moderate copy number vector (1560 copies) bearing the uspA promoter, reaching 4.6 mg/g dry cell weight (DCW) of ZZ-proinsulin secreted to the periplasm and 1.9 mg/g DCW secreted to the culture medium. These values are about 1.7-fold higher than those previously reported with the same ZZ fusion tag and the SpA leader peptide showing that these stress promoters are potentially valuable for recombinant protein secretion in E. coli. It is further demonstrated that the use of M9 minimal medium is advantageous for protein secretion as compared to LB rich medium.
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| 19. |
- Sandén, Anna Maria, et al.
(author)
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Limiting factors in Escherichia coli fed-batch production of recombinant proteins
- 2003
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In: Biotechnology and Bioengineering. - : Wiley. - 0006-3592 .- 1097-0290. ; 81:2, s. 158-166
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Journal article (peer-reviewed)abstract
- Fed-batch production of recombinant beta-galactosidase in E. coli was studied with respect to the specific growth rate at induction. The cultivations were designed to induce protein production by IPTG at a glucose feed rate corresponding to high (mu = 0.5 h(-1)) or low (mu = 0.1 h(-1)) specific growth rate. Protein production rate was approximately 100% higher at the higher specific growth rate, resulting in the accumulation of beta-galactosidase up to 30% of the total cell protein. Transcription analysis showed that beta-galactosidase-specific messenger RNA was immediately formed after induction (<5 min), but the amount was the same in both cases and was thus not the initial limiting factor. The content of ribosomes, as represented by rRNA, rapidly decreased with specific growth rate from a relative level of 100%, at the high specific growth rate, to 20% at the low specific growth rate. At high specific growth rate, ribosomes were additionally degraded upon induction due to the high production level. Translation therefore seemed to be the initial limiting factor of the protein synthesis capacity. The alarmone guanosine tetraphosphate increased at both high and low feed level inductions, indicating an induction-forced starvation of charged tRNA and/or glucose. The altered physiological status was also detected by the formation of acetic acid. However, the higher production rate resulted in high-level accumulation of acetic acid, which was absent at low feed rate production. Acetic acid production is thus coupled to the high product formation rate and is proposed to be due either to a precursor drain of Krebs cycle intermediates and a time lag before induction of the glyoxalate shunt, or to single amino acid overflow, since the model product is relatively poor in glycin and alanin. In conclusion, it is proposed that production at high specific growth rate becomes precursor-limited, while production at low specific growth rate is carbon- and/or energy-limited.
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| 20. |
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| 21. |
- Hanly, J G, et al.
(author)
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Autoantibodies and neuropsychiatric events at the time of systemic lupus erythematosus diagnosis
- 2008
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In: Arthritis and Rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 58:3, s. 843-853
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Journal article (peer-reviewed)abstract
- Objective. To examine, in an inception cohort of systemic lupus erythematosus (SLE) patients, the association between neuropsychiatric (NP) events and anti-ribosomal P (anti-P), antiphospholipid (lupus anticoagulant [LAC], anticardiolipin), anti-beta 2-glycoprotein I, and anti-NR2 glutamate receptor antibodies. Methods. NP events were identified using the American College of Rheumatology case definitions and clustered into central/peripheral and diffuse/focal events. Attribution of NP events to SLE was determined using decision rules of differing stringency. Autoantibodies were measured without knowledge of NP events or their attribution. Results. Four hundred twelve patients were studied (87.4% female; mean +/- SD age 34.9 +/- 13.5 years, mean +/- SD disease duration 5.0 +/- 4.2 months). There were 214 NP events in 133 patients (32.3%). The proportion of NP events attributed to SLE varied from 15% to 36%. There was no association between autoantibodies and NP events overall. However, the frequency of anti-P antibodies in patients with central NP events attributed to SLE was 4 of 20 (20%), versus 3 of 107 (2.8%) in patients with other NP events and 24 of 279 (8.6%) in those with no NP events (P = 0.04). Among patients with diffuse NP events, 3 of 11 had anti-P antibodies (27%), compared with 4 of 111 patients with other NP events (3.6%) and 24 of 279 of those with no NP events (8.6%) (P 0.02). Specific clinical-serologic associations were found between anti-P and psychosis attributed to SLE (P = 0.02) and between LAC and cerebrovascular disease attributed to SLE (P = 0.038). There was no significant association between other autoantibodies and NP events. Conclusion. Clinically distinct NP events attributed to SLE and occurring around the time of diagnosis were found to be associated with anti-P antibodies and LAC. This Suggests that there are different autoimmune pathogenetic mechanisms, although low sensitivity limits the clinical application of testing for these antibodies.
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| 22. |
- Hanly, J. G., et al.
(author)
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Neuropsychiatric events at the time of diagnosis of systemic lupus erythematosus - An international inception cohort study
- 2007
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In: Arthritis and Rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 56:1, s. 265-273
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Journal article (peer-reviewed)abstract
- Objective. To describe the prevalence, characteristics, attribution, and clinical significance of neuropsychiatric (NP) events in an international inception cohort of systemic lupus erythematosus (SLE) patients. Methods. The study was conducted by the Systemic Lupus International Collaborating Clinics (SLICC). Patients were enrolled within 15 months of fulfilling the American College of Rheumatology (ACR) SLE classification criteria. All NP events within a predefined enrollment window were identified using the ACR case definitions of 19 NP syndromes. Decision rules were derived to determine the proportion of NP disease attributable to SLE. Clinical significance was determined using the Short Form 36 (SF-36) Health Survey and the SLICC/ACR Damage Index (SDI). Results. A total of 572 patients (88% female) were recruited, with a mean +/- SD age of 35 +/- 14 years. The mean +/- SD disease duration was 5.2 +/- 4.2 months. Within the enrollment window, 158 of 572 patients (28%) had at least 1 NP event. In total, there were 242 NP events that encompassed 15 of 19 NP syndromes. The proportion of NP events attributed to SLE varied from 19% to 38% using alternate attribution models and occurred in 6.1-11.7% of patients. Those with NP events, regardless of attribution, had lower scores on the SF-36 and higher SDI scores compared with patients with no NP events. Conclusion. Twenty-eight percent of SLE patients experienced at least 1 NP event around the time of diagnosis of SLE, of which only a minority were attributed to SLE. Regardless of attribution, the occurrence of NP events was associated with reduced quality of life and increased organ damage.
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| 23. |
- Hanly, John G., et al.
(author)
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Neuropsychiatric Events in Systemic Lupus Erythematosus : Predictors of Occurrence and Resolution in a Longitudinal Analysis of an International Inception Cohort
- 2021
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In: Arthritis and Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 73:12, s. 2293-2302
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Journal article (peer-reviewed)abstract
- Objective: To determine predictors of change in neuropsychiatric (NP) event status in a large, prospective, international inception cohort of patients with systemic lupus erythematosus (SLE). Methods: Upon enrollment and annually thereafter, NP events attributed to SLE and non-SLE causes and physician-determined resolution were documented. Factors potentially associated with the onset and resolution of NP events were determined by time-to-event analysis using a multistate modeling structure. Results: NP events occurred in 955 (52.3%) of 1,827 patients, and 593 (31.0%) of 1,910 unique events were attributed to SLE. For SLE-associated NP (SLE NP) events, multivariate analysis revealed a positive association with male sex (P = 0.028), concurrent non-SLE NP events excluding headache (P < 0.001), active SLE (P = 0.012), and glucocorticoid use (P = 0.008). There was a negative association with Asian race (P = 0.002), postsecondary education (P = 0.001), and treatment with immunosuppressive drugs (P = 0.019) or antimalarial drugs (P = 0.056). For non-SLE NP events excluding headache, there was a positive association with concurrent SLE NP events (P < 0.001) and a negative association with African race (P = 0.012) and Asian race (P < 0.001). NP events attributed to SLE had a higher resolution rate than non-SLE NP events, with the exception of headache, which had comparable resolution rates. For SLE NP events, multivariate analysis revealed that resolution was more common in patients of Asian race (P = 0.006) and for central/focal NP events (P < 0.001). For non-SLE NP events, resolution was more common in patients of African race (P = 0.017) and less common in patients who were older at SLE diagnosis (P < 0.001). Conclusion: In a large and long-term study of the occurrence and resolution of NP events in SLE, we identified subgroups with better and worse prognosis. The course of NP events differs greatly depending on their nature and attribution.
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| 24. |
- Hanly, J. G., et al.
(author)
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Short-term outcome of neuropsychiatric events in systemic lupus erythematosus upon enrollment into an international inception cohort study
- 2008
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In: Arthritis and Rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 59:5, s. 721-729
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Journal article (peer-reviewed)abstract
- Objective. To determine the short-term outcome of neuropsychiatric (NP) events upon enrollment into an international inception cohort of patients with systemic lupus erythematosus (SLE). Methods. The study was performed by the Systemic Lupus International Collaborating Clinics. Patients were enrolled within 15 months of SLE diagnosis and NP events were characterized using the American College of Rheumatology case definitions. Decision rules were derived to identify NP events attributable to SLE. Physician outcome scores of NP events and patient-derived mental component summary (MCS) and physical component summary (PCS) scores of the Short Form 36 were recorded. Results. There were 890 patients (88.7% female) with a mean +/- SD age of 33.8 +/- 13.4 years and mean disease duration of 5.3 +/- 4.2 months. Within the enrollment window, 271 (33.5%) of 890 patients had at least 1 NP event encompassing 15 NP syndromes. NP events attributed to SLE varied from 16.5% to 33.9% using alternate attribution models and occurred in 6.0-11.5% of patients. Outcome scores for NP events attributed to SLE were significantly better than for NP events due to non-SLE causes. Higher global disease activity was associated with worse outcomes. MCS scores were lower in patients with NP events, regardless of attribution, and were also lower in patients with diffuse and central NP events. There was a significant association between physician outcome scores and patient MCS scores only for NP events attributed to SLE. Conclusion. In SLE patients, the short-term outcome of NP events is determined by both the characteristics and attribution of the events. Conclusion. In SLE patients, the short-term outcome of NP events is determined by both the characteristics and attribution of the events.
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| 25. |
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| 26. |
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| 27. |
- Hanly, JG, et al.
(author)
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Prospective analysis of neuropsychiatric events in an international disease inception cohort of patients with systemic lupus erythematosus
- 2010
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In: Annals of the rheumatic diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 69:3, s. 529-535
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Journal article (peer-reviewed)abstract
- To determine the frequency, accrual, attribution and outcome of neuropsychiatric (NP) events and impact on quality of life over 3 years in a large inception cohort of patients with systemic lupus erythematosus (SLE).MethodsThe study was conducted by the Systemic Lupus International Collaborating Clinics. Patients were enrolled within 15 months of SLE diagnosis. NP events were identified using the American College of Rheumatology case definitions, and decision rules were derived to determine the proportion of NP disease attributable to SLE. The outcome of NP events was recorded and patient-perceived impact determined by the SF-36.Results1206 patients (89.6% female) with a mean (±SD) age of 34.5±13.2 years were included in the study. The mean disease duration at enrolment was 5.4±4.2 months. Over a mean follow-up of 1.9±1.2 years, 486/1206 (40.3%) patients had ≥1 NP events, which were attributed to SLE in 13.0–23.6% of patients using two a priori decision rules. The frequency of individual NP events varied from 47.1% (headache) to 0% (myasthenia gravis). The outcome was significantly better for those NP events attributed to SLE, especially if they occurred within 1.5 years of the diagnosis of SLE. Patients with NP events, regardless of attribution, had significantly lower summary scores for both mental and physical health over the study.ConclusionsNP events in patients with SLE are of variable frequency, most commonly present early in the disease course and adversely impact patients' quality of life over time. Events attributed to non-SLE causes are more common than those due to SLE, although the latter have a more favourable outcome.
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| 28. |
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| 29. |
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| 30. |
- Isenberg, D. A., et al.
(author)
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An assessment of disease flare in patients with systemic lupus erythematosus: a comparison of BILAG 2004 and the flare version of SELENA
- 2011
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In: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 70:1, s. 54-59
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Journal article (peer-reviewed)abstract
- Aims To compare the British Isles Lupus Assessment Group (BILAG) 2004, the Safety of Estrogens in Lupus Erythematosus National Assessment (SELENA) flare index (SFI) and physician's global assessment (PGA) in assessing flares of disease activity in patients with systemic lupus erythematosus (SLE). Methods Sixteen patients with active SLE were assessed by a panel of 16 rheumatologists. The order in which the patients were seen was randomised using a 4x4 Latin square design. Each patient's flare status was determined at each assessment using the BILAG 2004 activity index; the SFI and a PGA. A group of five specialists designated each patient into severe, moderate, mild or no flare categories. Results The rate of complete agreement (95% CI) of the four individual examining physicians for any flare versus no flare was 81% (55% to 94%), 75% (49% to 90%) and 75% (49% to 90%) for the BILAG 2004 index, SELENA flare instrument and PGA, respectively. The overall agreement between flare defined by BILAG 2004 and the SFI was 81% and when type of flare was considered was 52%. Intraclass correlation coefficients (95% CI), as a measure of internal reliability, were 0.54 (0.32 to 0.78) for BILAG 2004 flare compared with 0.21 (0.08 to 0.48) for SELENA flare and 0.18 (0.06 to 0.45) for PGA. Severe flare was associated with good agreement between the indices but mild/moderate flare was much less consistent. Conclusions The assessment of flare in patients with SLE is challenging. No flare and severe flare are identifiable but further work is needed to optimise the accurate 'capture' of mild and moderate flares.
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| 31. |
- Ugarte-Gil, Manuel Francisco, et al.
(author)
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Impact of glucocorticoids on the incidence of lupus-related major organ damage : A systematic literature review and meta-regression analysis of longitudinal observational studies
- 2021
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In: Lupus Science and Medicine. - : BMJ. - 2053-8790. ; 8:1
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Research review (peer-reviewed)abstract
- Objective In systemic lupus erythematosus (SLE), disease activity and glucocorticoid (GC) exposure are known to contribute to irreversible organ damage. We aimed to examine the association between GC exposure and organ damage occurrence. Methods We conducted a literature search (PubMed (Medline), Embase and Cochrane January 1966-October 2021). We identified original longitudinal observational studies reporting GC exposure as the proportion of users and/or GC use with dose information as well as the occurrence of new major organ damage as defined in the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index. Meta-regression analyses were performed. Reviews, case-reports and studies with <5 years of follow-up, <50 patients, different outcomes and special populations were excluded. Results We selected 49 articles including 16 224 patients, 14 755 (90.9%) female with a mean age and disease duration of 35.1 years and of 37.1 months. The mean follow-up time was 104.9 months. For individual damage items, the average daily GC dose was associated with the occurrence of overall cardiovascular events and with osteoporosis with fractures. A higher average cumulative dose adjusted (or not)/number of follow-up years and a higher proportion of patients on GC were associated with the occurrence of osteonecrosis. Conclusions We confirm associations of GC use with three specific damage items. In treating patients with SLE, our aim should be to maximise the efficacy of GC and to minimise their harms.
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| 32. |
- Clarke, Ann E., et al.
(author)
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Assessing the Costs of Neuropsychiatric Disease in the Systemic Lupus International Collaborating Clinics Cohort Using Multistate Modeling
- 2023
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In: Arthritis Care and Research. - : Wiley. - 2151-464X .- 2151-4658. ; 75:9, s. 1859-1870
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Journal article (peer-reviewed)abstract
- Objective: To estimate direct and indirect costs associated with neuropsychiatric (NP) events in the Systemic Lupus International Collaborating Clinics inception cohort. Methods: NP events were documented annually using American College of Rheumatology definitions for NP events and attributed to systemic lupus erythematosus (SLE) or non-SLE causes. Patients were stratified into 1 of 3 NP states (no, resolved, or new/ongoing NP event). Change in NP status was characterized by interstate transition rates using multistate modeling. Annual direct costs and indirect costs were based on health care use and impaired productivity over the preceding year. Annual costs associated with NP states and NP events were calculated by averaging all observations in each state and adjusted through random-effects regressions. Five- and 10-year costs for NP states were predicted by multiplying adjusted annual costs per state by expected state duration, forecasted using multistate modeling. Results: A total of 1,697 patients (49% White race/ethnicity) were followed for a mean of 9.6 years. NP events (n = 1,971) occurred in 956 patients, 32% attributed to SLE. For SLE and non-SLE NP events, predicted annual, 5-, and 10-year direct costs and indirect costs were higher in new/ongoing versus no events. Direct costs were 1.5-fold higher and indirect costs 1.3-fold higher in new/ongoing versus no events. Indirect costs exceeded direct costs 3.0 to 5.2 fold. Among frequent SLE NP events, new/ongoing seizure disorder and cerebrovascular disease accounted for the largest increases in annual direct costs. For non-SLE NP events, new/ongoing polyneuropathy accounted for the largest increase in annual direct costs, and new/ongoing headache and mood disorder for the largest increases in indirect costs. Conclusion: Patients with new/ongoing SLE or non-SLE NP events incurred higher direct and indirect costs.
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| 33. |
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| 34. |
- Hanly, John G., et al.
(author)
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Neuropsychiatric events in systemic lupus erythematosus : A longitudinal analysis of outcomes in an international inception cohort using a multistate model approach
- 2020
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In: Annals of the Rheumatic Diseases. - : BMJ. - 0003-4967 .- 1468-2060. ; 79:3, s. 356-362
-
Journal article (peer-reviewed)abstract
- Objectives: Using a reversible multistate model, we prospectively examined neuropsychiatric (NP) events for attribution, outcome and association with health-related quality of life (HRQoL), in an international, inception cohort of systemic lupus erythematosus (SLE) patients. Methods: Annual assessments for 19 NP events attributed to SLE and non-SLE causes, physician determination of outcome and patient HRQoL (short-form (SF)-36 scores) were measured. Time-to-event analysis and multistate modelling examined the onset, recurrence and transition between NP states. Results: NP events occurred in 955/1827 (52.3%) patients and 592/1910 (31.0%) unique events were attributed to SLE. In the first 2 years of follow-up the relative risk (95% CI) for SLE NP events was 6.16 (4.96, 7.66) and non-SLE events was 4.66 (4.01, 5.43) compared with thereafter. Patients without SLE NP events at initial assessment had a 74% probability of being event free at 10 years. For non-SLE NP events the estimate was 48%. The majority of NP events resolved over 10 years but mortality was higher in patients with NP events attributed to SLE (16%) versus patients with no NPSLE events (6%) while the rate was comparable in patients with non-SLE NP events (7%) compared with patients with no non-SLE events (6%). Patients with NP events had lower SF-36 summary scores compared with those without NP events and resolved NP states (p<0.001). Conclusions: NP events occur most frequently around the diagnosis of SLE. Although the majority of events resolve they are associated with reduced HRQoL and excess mortality. Multistate modelling is well suited for the assessment of NP events in SLE.
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| 35. |
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| 36. |
- Aertsen, A., et al.
(author)
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Heat shock protein-mediated resistance to high hydrostatic pressure in Escherichia coli
- 2004
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In: Applied and Environmental Microbiology. - 0099-2240. ; 70:5, s. 2660-2666
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Journal article (peer-reviewed)abstract
- A random library of Escherichia coli MG1655 genomic fragments fused to a promoterless green fluorescent protein (GFP) gene was constructed and screened by differential fluorescence induction for promoters that are induced after exposure to a sublethal high hydrostatic pressure stress. This screening yielded three promoters of genes belonging to the heat shock regulon (dnaK, lon, clpPX), suggesting a role for heat shock proteins in protection against, and/or repair of, damage caused by high pressure. Several further observations provide additional support for this hypothesis: (i) the expression of rpoH, encoding the heat shock-specific sigma factor {sigma}32, was also induced by high pressure; (ii) heat shock rendered E. coli significantly more resistant to subsequent high-pressure inactivation, and this heat shock-induced pressure resistance followed the same time course as the induction of heat shock genes; (iii) basal expression levels of GFP from heat shock promoters, and expression of several heat shock proteins as determined by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis of proteins extracted from pulse-labeled cells, was increased in three previously isolated pressure-resistant mutants of E. coli compared to wild-type levels.
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| 37. |
- Ederth, Josefine, 1974-
(author)
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The Role of the Escherichia coli RNA Polymerase β´Jaw in Transcription
- 2004
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Doctoral thesis (other academic/artistic)abstract
- Transcription, the central step in gene expression and regulation, is carried out by the DNA-dependent RNA polymerase (RNAP). Bacterial RNAP is a complex molecular machine in which the network of interacting parts and their movements, including contacts to nascent RNA and the DNA template, are at best partially understood.In this work, the aim has been to elucidate the role of the RNAP jaw-domain, which is part of the RNAPs largest subunit ( β´), in transcription. The jaw-domain is interesting because of its close proximity to downstream DNA in the complex. Downstream DNA is known as a component involved in all three steps of transcription. However, the key role it plays in regulating the enzyme´s activity is far from understood.Initially, two novel mutations in the β´ jaw-domain were isolated and characterized in vivo. It was shown that the jaw-domain has specific effects on regulation of the ColE1 plasmid copy number, likely via different effects on initiation at the RNA Iand RNA II- promoters.Further, in vitro characterisations indicate that contacts of the jaw-domain to downstream DNA, at the leading edge of the transcription complex, contribute to regulation during all three phases of transcription. The results provide insight into the role of the jaw-domain-downstream DNA contact in transcription initiation and pausing, and suggest possible explanations for the previously reported effects on ColEI plasmid copy number.The RNAP jaw-domain is situated at ~30 Å distance from the active site. Suppressor mutations were selected to gain further knowledge of how the jaw-domain can exert such profound effects on the enzyme´s activity. Allele specific suppressor mutations were found in the rifampicin-pocket, only a few Ångströms away from the active site. It is shown that the suppressor substitutions compensate for the jawdeletion RNAPs defects in transcriptional pausing and inability to grow at elevated temperatures. These same substitutions exacerbate the jaw-deletion´s defect at transcription initiation, which suggests that the elongation defects are responsible for the temperature sensitive growth phenotype of the jaw-deletion strain. In light of the RNAP crystal structures available, a possible mechanism for counteracting effects on the active site mediated by the suppressor mutations and the jaw-deletion is suggested.
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| 38. |
- Gholami, Asma, et al.
(author)
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Discovery of novel inhibitors for Pseudomonas aeruginosa lipase enzyme from in silico and in vitro studies
- 2024
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In: Journal of Biomolecular Structure & Dynamics. - 0739-1102. ; 42:5, s. 2197-2210
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Journal article (peer-reviewed)abstract
- Pseudomonas aeruginosa is an opportunistic pathogen prone to developing drug-resistance and is a major cause of infection for burn patients and patients suffering from cystic fibrosis or are hospitalized in intensive care units. One of the virulence factors of this bacterium is the lipase enzyme that degrades the extracellular matrix of the host tissue and promotes invasion. Bromhexine is a mucolytic drug and has recently been reported to function as a competitive inhibitor of lipase with an IC50 value of 49 mu M. In the present study, an attempt was made to identify stronger inhibitors from the ChEMBL database of bioactive compounds, as compared to the reference compound Bromhexine. Following docking and MD simulations, four hit compounds (N1-N4) were selected that showed promising binding modes and low RMSD values indicative of stable protein-ligand complexes. From subsequent binding pose metadynamics (BPMD) simulations, two of these (N2 and N4) stood out as more potent than Bromhexine, displaying stable interactions with residues in the catalytic site of the enzyme. Biological investigations were performed for all four compounds. Among them, the same two hit compounds were found to be the most effective binders with IC50 values of 22.1 and 27.5 mu M, respectively; i.e. roughly twice as efficient as the reference Bromhexine. Taken together, our results show that these hits can be promising new candidates to use as leads for the development of drugs targeting the P. aeruginosa lipase enzyme.Communicated by Ramaswamy H. Sarma
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| 39. |
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| 40. |
- Wahlgren, Weixiao Yuan, 1970, et al.
(author)
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Substrate-bound outward-open structure of a Na+-coupled sialic acid symporter reveals a new Na+ site.
- 2018
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In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9:1
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Journal article (peer-reviewed)abstract
- Many pathogenic bacteria utilise sialic acids as an energy source or use them as an external coating to evade immune detection. As such, bacteria that colonise sialylated environments deploy specific transporters to mediate import of scavenged sialic acids. Here, we report a substrate-bound 1.95Å resolution structure and subsequent characterisation of SiaT, a sialic acid transporter from Proteus mirabilis. SiaT is a secondary active transporter of the sodium solute symporter (SSS) family, which use Na+ gradients to drive the uptake of extracellular substrates. SiaT adopts the LeuT-fold and is in an outward-open conformation in complex with the sialic acid N-acetylneuraminic acid and two Na+ ions. One Na+ binds to the conserved Na2 site, while the second Na+ binds to a new position, termed Na3, which is conserved in many SSS family members. Functional and molecular dynamics studies validate the substrate-binding site and demonstrate that both Na+ sites regulate N-acetylneuraminic acid transport.
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