| 1. |
|
|
| 2. |
- Ruiz-Pavon, Lorena, et al.
(author)
-
Functionally important amino acids in the Arabidopsis thylakoid phosphate transporter: Homology modeling and site-directed mutagenesis
- 2010
-
In: Biochemistry. - : American Chemical Society. - 0006-2960 .- 1520-4995. ; 49:30, s. 6430-6439
-
Journal article (peer-reviewed)abstract
- The anion transporter 1 (ANTR1) from Arabidopsis thaliana, homologous to the mammalian members of the solute carrier 17 (SLC17) family, is located in the chloroplast thylakoid membrane. When expressed heterologously in Escherichia coli, ANTR1 mediates a Na+-dependent active transport of inorganic phosphate (Pi). The aim of this study was to identify amino acid residues involved in Pi binding and translocation by ANTR1 and in the Na+ dependence of its activity. A three-dimensional structural model of ANTR1 was constructed using the crystal structure of glycerol 3-phosphate/phosphate antiporter from E. coli as a template. Based on this model and multiple sequence alignments, five highly conserved residues in plant ANTRs and mammalian SLC17 homologues have been selected for site-directed mutagenesis, namely, Arg-120, Ser-124, and Arg-201 inside the putative translocation pathway and Arg-228 and Asp-382 exposed at the cytoplasmic surface of the protein. The activities of the wild-type and mutant proteins have been analyzed using expression in E. coli and radioactive Pi transport assays and compared with bacterial cells carrying an empty plasmid. The results from Pi- and Na+-dependent kinetics indicate the following: (i) Arg-120 and Arg-201 may be important for binding and translocation of the substrate; (ii) Ser-124 may function as a transient binding site for Na+ ions in close proximity to the periplasmic side; (iii) Arg-228 and Asp-382 may participate in interactions associated with protein conformational changes required for full transport activity. Functional characterization of ANTR1 should provide useful insights into the function of other plant and mammalian SLC17 homologous transporters.
|
|
| 3. |
- Ruiz-Pavon, L, et al.
(author)
-
Modeling and Mutational analysis of Anion transporter 1 protein of Arabidopsis thaliana
- 2010
-
In: The FEBS Journal. - : Wiley-Blackwell. - 1742-464X .- 1742-4658. ; 277:Suppl. 1, s. 231-231
-
Journal article (other academic/artistic)abstract
- The thylakoid anion transporter 1 (ANTR1) from Arabidopsisthaliana, has been characterized as a Na-dependent Pi transporter when expressed in E. coli (1), but no data is yet available for the protein structure and amino acids involved in transport of Pi. In this study a three-dimensional structural model of ANTR1 was constructed in silico using the crystal structure of glycerol-3- phosphate/phosphate antiporter from E. coli as a template. Based on Multiple Sequence Alignments (MSAs) with other plant ANT- Rs and mammalian SLC17 homologues, five highly conserved amino acids involved in Pi transport have been identified, namely Arg-120, Ser-124 and Arg-201 inside the putative translocation pathway, Arg-228 and Asp-382 exposed at the cytoplasmic sur- face of the protein. The activity of the protein as a Na-dependent Pi transporter in the wild type and mutants was analyzed by het- erologous expression and uptake of radioactive Pi into E. coli cells. Substitution of the three Arg (120, 201 and 228) for Glu residues and of Asp-382 for an Asn residue resulted in an inac- tive ANTR1 transporter. All other mutants had sufficient activity to allow measurement of kinetic parameters, attesting that the mutated proteins were functional. Based on our results, we pro- pose that Arg-201 is a critical residue for substrate binding and translocation, whereas Ser-124 may function as periplasmic gate- way for Na+ ions. Residue Arg-120 plays an important role in Pi binding and associated conformational changes, and finally that Arg-228 and Asp-382 only weakly participate in interactions allowing conformational changes to occur at the cytoplasmic sur-face of the transporter.
|
|
| 4. |
- Asp, Michaela, et al.
(author)
-
Spatial detection of fetal marker genes expressed at low level in adult human heart tissue
- 2017
-
In: Scientific Reports. - : NATURE PUBLISHING GROUP. - 2045-2322. ; 7
-
Journal article (peer-reviewed)abstract
- Heart failure is a major health problem linked to poor quality of life and high mortality rates. Hence, novel biomarkers, such as fetal marker genes with low expression levels, could potentially differentiate disease states in order to improve therapy. In many studies on heart failure, cardiac biopsies have been analyzed as uniform pieces of tissue with bulk techniques, but this homogenization approach can mask medically relevant phenotypes occurring only in isolated parts of the tissue. This study examines such spatial variations within and between regions of cardiac biopsies. In contrast to standard RNA sequencing, this approach provides a spatially resolved transcriptome- and tissue-wide perspective of the adult human heart, and enables detection of fetal marker genes expressed by minor subpopulations of cells within the tissue. Analysis of patients with heart failure, with preserved ejection fraction, demonstrated spatially divergent expression of fetal genes in cardiac biopsies.
|
|
| 5. |
|
|
| 6. |
- Clyne, N, et al.
(author)
-
The intracellular distribution of cobalt in exposed and unexposed rat myocardium
- 1990
-
In: Scandinavian Journal of Clinical and Laboratory Investigation. - 0036-5513 .- 1502-7686. ; 50:6, s. 605-609
-
Journal article (peer-reviewed)abstract
- The intracellular distribution of cobalt was analysed in the myocardium of exposed and unexposed rats. The exposed rats were given a dietary cobalt supplementation of 40 mg CoS04-7 H20/kg body weight for 8 weeks. The mitochondrial fraction showed the greatest relative increase in cobalt: 0.09 ng/mg protein in the unexposed rats to 8.43 ng/mg protein in the exposed rats. In the exposed rats the submitochondrial particles had the highest levels of cobalt: 19.43 ng/mg protein, followed by the sarcoplasmatic reticulum: 12.3 ng/mg protein. The microsomal 44 000g supernatant also showed an increase, although the levels remained low (0.51 ng/mg protein in the exposed animals). Apparently the calcium-storing organelles had the highest levels of cobalt. This could affect calcium flux in myocardial cells and, secondarily, tension development in cardiac muscle.
|
|
| 7. |
- Flores-Langarica, Adriana, et al.
(author)
-
Intestinal CD103+CD11b+ cDC2 conventional dendritic cells are required for primary CD4+ T and B cell responses to soluble flagellin
- 2018
-
In: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 9:OCT
-
Journal article (peer-reviewed)abstract
- Systemic immunization with soluble flagellin (sFliC) from Salmonella Typhimurium induces mucosal responses, offering potential as an adjuvant platform for vaccines. Moreover, this engagement of mucosal immunity is necessary for optimal systemic immunity, demonstrating an interaction between these two semi-autonomous immune systems. Although TLR5 and CD103+CD11b+ cDC2 contribute to this process, the relationship between these is unclear in the early activation of CD4+ T cells and the development of antigen-specific B cell responses. In this work, we use TLR5-deficient mice and CD11c-cre.Irf4fl/fl mice (which have reduced numbers of cDC2, particularly intestinal CD103+CD11b+ cDCs), to address these points by studying the responses concurrently in the spleen and the mesenteric lymph nodes (MLN). We show that CD103+CD11b+ cDC2 respond rapidly and accumulate in the MLN after immunization with sFliC in a TLR5-dependent manner. Furthermore, we identify that whilst CD103+CD11b+ cDC2 are essential for the induction of primary T and B cell responses in the mucosa, they do not play such a central role for the induction of these responses in the spleen. Additionally, we show the involvement of CD103+CD11b+ cDC2 in the induction of Th2-associated responses. CD11c-cre.Irf4fl/fl mice showed a reduced primary FliC-specific Th2-associated IgG1 responses, but enhanced Th1-associated IgG2c responses. These data expand our current understanding of the mucosal immune responses promoted by sFliC and highlights the potential of this adjuvant for vaccine usage by taking advantage of the functionality of mucosal CD103+CD11b+ cDC2.
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
|
|
| 11. |
|
|
| 12. |
- Momeni, Naghi, et al.
(author)
-
A novel blood-based biomarker for detection of autism spectrum disorders
- 2012
-
In: Translational Psychiatry. - : Nature Publishing Group. - 2158-3188. ; 2
-
Journal article (peer-reviewed)abstract
- Autism Spectrum Disorders (ASD) are classified as neurological developmental disorders. Several studies have been carried out to find a candidate biomarker linked to development of these disorders, but up to date no reliable biomarker is available. Mass spectrometry techniques have been used for protein profiling of blood plasma of children with such disorders in order to identify proteins/peptides which may be used as biomarkers for detection of the disorders. Three differentially expressed peptides with mass charged (m/z) values of 2,020 ± 1, 1,864 ± 1, and 1,978 ± 1 Da in heparin plasma of children with ASD which were significantly changed as compared to the peptide pattern of the non-ASD control group are reported here. This novel set of biomarkers allows for a reliable blood based diagnostic tool that may be used in diagnosis and potentially, in prognosis of ASD.
|
|
| 13. |
|
|
| 14. |
- Momeni, Naghi, et al.
(author)
-
High complement factor I activity in the plasma of children with autism spectrum disorders
- 2012
-
In: Autism Research and Treatment. - : Hindawi Publishing Corporation. - 2090-1925 .- 2090-1933.
-
Journal article (peer-reviewed)abstract
- Autism spectrum disorders (ASDs) are neurodevelopmental and behavioural syndromes affecting social orientation, behaviour, and communication that can be classified as developmental disorders. ASD is also associated with immune system abnormality. Immune system abnormalities may be caused partly by complement system factor I deficiency. Complement factor I is a serine protease present in human plasma that is involved in the degradation of complement protein C3b, which is a major opsonin of the complement system. Deficiency in factor I activity is associated with an increased incidence of infections in humans. In this paper, we show that the mean level of factor I activity in the ASD group is significantly higher than in the control group of typically developed and healthy children, suggesting that high activity of complement factor I might have an impact on the development of ASD.
|
|
| 15. |
|
|
| 16. |
- Persson, Bengt L., et al.
(author)
-
Energy-linked nicotinamide nucleotide transhydrogenase : Properties of proton-translocating mitochondrial transhydrogenase from beef heart purified by fast protein liquid chromatography
- 1984
-
In: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 259, s. 8626-8632
-
Journal article (peer-reviewed)abstract
- Mitochondrial nicotinamide nucleotide transhydrogenasefrom beef heart was purified by a novel procedureinvolving fast protein liquid chromatography andcharacterized with respect to molecular and catalyticproperties. The method is reproducible, gives highlypure transhydrogenase as judged by silver staining,and can be modified to produce large amounts of puretranshydrogenase protein suitable for e.g. sequencingand other protein chemical studies.Transhydrogenase purified by fast protein liquidchromatography is reconstitutively active and pumpsprotons as indicated by an extensive quenching of 9-aminoacridine fluorescence. Under conditions whichgenerate a proton gradient in the absence of a membranepotential the activity of reconstituted transhydrogenaseis close to zero indicating a complete andproper incorporation in the membrane and a preferentialregulation of the enzyme by a proton gradientrather than a membrane potential.Treatment of reconstituted transhydrogenase withN,N-dicyclohexylcarbodiimide results in an inhibitionof proton pump activity without an effect on uncoupledcatalytic activity, suggestingt hat proton translocationand catalytic activities are not obligatory linked orthat this agent separates proton pumping from thecatalytic activity.
|
|
| 17. |
|
|
| 18. |
- Persson, Bengt, et al.
(author)
-
The SDR (short-chain dehydrogenase/reductase and related enzymes) nomenclature initiative
- 2009
-
In: Chemico-Biological Interactions. - : Elsevier BV. - 0009-2797 .- 1872-7786. ; 178:1-3, s. 94-98
-
Journal article (peer-reviewed)abstract
- Short-chain dehydrogenases/reductases (SDR) constitute one of the largest enzyme superfamilies with presently over 46,000 members. In phylogenetic comparisons, members of this superfamily show early divergence where the majority have only low pairwise sequence identity, although sharing common structural properties. The SDR enzymes are present in virtually all genomes investigated, and in humans over 70 SDR genes have been identified. In humans, these enzymes are involved in the metabolism of a large variety of compounds, including steroid hormones, prostaglandins, retinoids, lipids and xenobiotics. It is now clear that SDRs represent one of the oldest protein families and contribute to essential functions and interactions of all forms of life. As this field continues to grow rapidly, a systematic nomenclature is essential for future annotation and reference purposes. A functional subdivision of the SDR superfamily into at least 200 SDR families based upon hidden Markov models forms a suitable foundation for such a nomenclature system, which we present in this paper using human SDRs as examples.
|
|
| 19. |
|
|
| 20. |
|
|
| 21. |
- Svanberg, Sune, et al.
(author)
-
Applications of terawatt lasers
- 1994
-
In: LASER SPECTROSCOPY - XITH INTERNATIONAL CONFERENCE. - : AIP. - 1551-7616 .- 0094-243X. - 1563962624 ; :290, s. 264-269
-
Conference paper (peer-reviewed)
|
|
| 22. |
|
|
| 23. |
- van Dishoeck, E. F., et al.
(author)
-
Water in star-forming regions: Physics and chemistry from clouds to disks as probed by Herschel spectroscopy
- 2021
-
In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 648
-
Journal article (peer-reviewed)abstract
- Context. Water is a key molecule in the physics and chemistry of star and planet formation, but it is difficult to observe from Earth. The Herschel Space Observatory provided unprecedented sensitivity as well as spatial and spectral resolution to study water. The Water In Star-forming regions with Herschel (WISH) key program was designed to observe water in a wide range of environments and provide a legacy data set to address its physics and chemistry. Aims. The aim of WISH is to determine which physical components are traced by the gas-phase water lines observed with Herschel and to quantify the excitation conditions and water abundances in each of these components. This then provides insight into how and where the bulk of the water is formed in space and how it is transported from clouds to disks, and ultimately comets and planets. Methods. Data and results from WISH are summarized together with those from related open time programs. WISH targeted ∼80 sources along the two axes of luminosity and evolutionary stage: from low- to high-mass protostars (luminosities from <1 to > 10Lpdbl) and from pre-stellar cores to protoplanetary disks. Lines of H2O and its isotopologs, HDO, OH, CO, and [O I], were observed with the HIFI and PACS instruments, complemented by other chemically-related molecules that are probes of ultraviolet, X-ray, or grain chemistry. The analysis consists of coupling the physical structure of the sources with simple chemical networks and using non-LTE radiative transfer calculations to directly compare models and observations. Results. Most of the far-infrared water emission observed with Herschel in star-forming regions originates from warm outflowing and shocked gas at a high density and temperature (> 10cm-3, 300-1000 K, v ∼ 25 km s-1), heated by kinetic energy dissipation. This gas is not probed by single-dish low-J CO lines, but only by CO lines with Jup > 14. The emission is compact, with at least two different types of velocity components seen. Water is a significant, but not dominant, coolant of warm gas in the earliest protostellar stages. The warm gas water abundance is universally low: orders of magnitude below the H2O/H2 abundance of 4 × 10-4 expected if all volatile oxygen is locked in water. In cold pre-stellar cores and outer protostellar envelopes, the water abundance structure is uniquely probed on scales much smaller than the beam through velocity-resolved line profiles. The inferred gaseous water abundance decreases with depth into the cloud with an enhanced layer at the edge due to photodesorption of water ice. All of these conclusions hold irrespective of protostellar luminosity. For low-mass protostars, a constant gaseous HDO/H2O ratio of ∼0.025 with position into the cold envelope is found. This value is representative of the outermost photodesorbed ice layers and cold gas-phase chemistry, and much higher than that of bulk ice. In contrast, the gas-phase NH3 abundance stays constant as a function of position in low-mass pre- and protostellar cores. Water abundances in the inner hot cores are high, but with variations from 5 × 10-6 to a few × 10-4 for low- and high-mass sources. Water vapor emission from both young and mature disks is weak. Conclusions. The main chemical pathways of water at each of the star-formation stages have been identified and quantified. Low warm water abundances can be explained with shock models that include UV radiation to dissociate water and modify the shock structure. UV fields up to 102-10times the general interstellar radiation field are inferred in the outflow cavity walls on scales of the Herschel beam from various hydrides. Both high temperature chemistry and ice sputtering contribute to the gaseous water abundance at low velocities, with only gas-phase (re-)formation producing water at high velocities. Combined analyses of water gas and ice show that up to 50% of the oxygen budget may be missing. In cold clouds, an elegant solution is that this apparently missing oxygen is locked up in larger μm-sized grains that do not contribute to infrared ice absorption. The fact that even warm outflows and hot cores do not show H2O at full oxygen abundance points to an unidentified refractory component, which is also found in diffuse clouds. The weak water vapor emission from disks indicates that water ice is locked up in larger pebbles early on in the embedded Class I stage and that these pebbles have settled and drifted inward by the Class II stage. Water is transported from clouds to disks mostly as ice, with no evidence for strong accretion shocks. Even at abundances that are somewhat lower than expected, many oceans of water are likely present in planet-forming regions. Based on the lessons for galactic protostars, the low-J H2O line emission (Eup < 300 K) observed in extragalactic sources is inferred to be predominantly collisionally excited and to originate mostly from compact regions of current star formation activity. Recommendations for future mid- to far-infrared missions are made.
|
|
| 24. |
- Andersson, Michael R., et al.
(author)
-
Mutational analysis of conserved glutamic acids of Pho89, a Saccharomyces cerevisiae high-affinity inorganic phosphate:Na+ symporter
- 2012
-
In: Biologia. - : Springer Science and Business Media LLC. - 0006-3088 .- 1336-9563. ; 67:6, s. 1056-1061
-
Journal article (peer-reviewed)abstract
- In Saccharomyces cerevisiae, the high-affinity phosphate transport system comprises the Pho84 and Pho89 permeases. The Pho89 permease catalyzes import of inorganic phosphate in a symport manner by utilizing Na+ ions as co-solute. We have addressed the functional importance of two glutamic acid residues at positions 55 and 491. Both residues are highly conserved amongst members of the inorganic phosphate transporter (PiT) family, which might be an indication of functional importance. Moreover, both residues have been shown to be of critical importance in the hPit2 transporter. We have created site-directed mutations of both E55 and E491 to lysine and glutamine. We observed that in all four cases there is a dramatic impact on the transport activity, and thus it seems that they indeed are of functional importance. Following these observations, we addressed the membrane topology of this protein by using several prediction programs. TOPCONS predicts a 7-5 transmembrane segment organization, which is the most concise topology as compared to the hPiT2 transporter. By understanding the functionality of these residues, we are able to correlate the Pho89 topology to that of the hPiT2, and can now further analyze residues which might play a role in the transport activity.
|
|
| 25. |
|
|
| 26. |
- Basheer, Shabana, et al.
(author)
-
A membrane protein based biosensor: Use of a phosphate - H+ symporter membrane protein (Pho84) in the sensing of phosphate ions.
- 2011
-
In: Biosensors & bioelectronics. - : Elsevier. - 0956-5663 .- 1873-4235. ; 27:1, s. 58-63
-
Journal article (peer-reviewed)abstract
- A label free biosensor for direct detection of inorganic phosphate based on potential-step capacitance measurements has been developed. The high-affinity Pho84 plasma membrane phosphate/proton symporter of Saccharomyces cerevisiae was used as a sensing element. Heterologously expressed and purified Pho84 protein was immobilized on a self-assembled monolayer (SAM) on a capacitance electrode. Changes in capacitance were recorded upon exposure to phosphate compared to the control substance, phosphate analogue methylphosphonate. Hence, even without the explicit use of lipid membranes, the Pho84 membrane protein could retain its capacity of selective substrate binding, with a phosphate detection limit in the range of the apparent in vivo K(m). A linear increase in capacitance was monitored in the phosphate concentration range of 5-25 mu M. The analytical response of the capacitive biosensor is in agreement with that the transporter undergoes significant conformational changes upon exposure to inorganic phosphate, while exposure to the analogue only causes minor responses.
|
|
| 27. |
|
|
| 28. |
|
|
| 29. |
|
|
| 30. |
- Carlenor, E, et al.
(author)
-
On the presence of a nicotinamide nucleotide transhydrogenase in mitochondria from potato tuber
- 1988
-
In: Plant Physiology. - 0032-0889 .- 1532-2548. ; 88, s. 303-308
-
Journal article (peer-reviewed)abstract
- Mitochondria isolated from potato (Solanum tuberosum L.) tuber wereinvestigated for the presence of a nicotinamide nucleotide transhydrogenaseactivity. Submitochondrial particles derived from these mitochondriaby sonication catalyzed a reduction of NAD' or 3-acetylpyridine-NAD'by NADPH, which showed a maximum of about 50 to 150 nanomoles/minute. milligram protein at pH 5 to 6. The Km values for 3-acetylpyridine-NAD' and NADPH were about 24 and 55 micromolar, respectively.Intact mitochondria showed a negligible activity in the absence of detergents.However, in the presence of detergents the specific activity approachedabout 30% of that seen with submitochondrial particles. Thepotato mitochondria transhydrogenase activity was sensitive to trypsinand phenylarsine oxide, both agents that are known to inhibit the mammaliantranshydrogenase. Antibodies raised against rat liver transhydrogenasecrossreacted with two peptides in potato tuber mitochondrialmembranes with a molecular mass of 100 to 115 kilodaltons. Theobserved transhydrogenase activities may be due to an unspecific activityof dehydrogenases and/or to a genuine transhydrogenase. The activitycontributions by NADH dehydrogenases and transhydrogenase to thetotal transhydrogenase activity were investigated by determining theirrelative sensitivities to trypsin. It is concluded that, at high or neutralpH, the observed transhydrogenase activity in potato tuber submitochondrialparticles is due to the presence of a genuine and specific highmolecular weight transhydrogenase. At low pH an unspecific reaction ofan NADH dehydrogenase with NADPH contributes to the total transhydrogenaseactivity.
|
|
| 31. |
|
|
| 32. |
|
|
| 33. |
- Eytan, G D, et al.
(author)
-
Energy-linked nicotinamide-nucleotide transhydrogenase. Characterization of reconstituted ATP-driven transhydrogenase from beef heart mitochondria.
- 1987
-
In: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 262, s. 5008-5014
-
Journal article (peer-reviewed)abstract
- The interaction between pure transhydrogenase and ATPase (Complex V) from beef heart mitochondria was investigated with transhydrogenase-ATPase vesicles in which the two proteins were co-reconstituted by dialysis or dilution procedures. In addition to phosphatidylcholine and phosphatidylethanolamine, reconstitution required phosphatidylserine and lysophosphatidylcholine. Transhydrogenase-ATPase vesicles catalyzed a 20-30-fold stimulation of the reduction of NADP+ or thio-NADP+ by NADH and a 70-fold shift of the apparent equilibrium expressed as the nicotinamide nucleotide ratio [NADPH][NAD+]/[NADP+][NADH]. In both of these respects, the transhydrogenase-ATPase vesicles were severalfold more efficient than beef heart submitochondrial particles. By measuring the ATP-driven transhydrogenase and the oligomycin-sensitive ATPase activities simultaneously and under the same conditions at low ATP concentrations, i.e. below 15 microM, the ATP-driven transhydrogenase/oligomycin-sensitive ATPase activity ratio was found to be about 3. This value is consistent with the stoichiometries of three protons translocated per ATP hydrolyzed and one proton translocated per NADPH formed and with a mechanism where the two enzymes interact through a delocalized proton-motive force.
|
|
| 34. |
|
|
| 35. |
|
|
| 36. |
|
|
| 37. |
|
|
| 38. |
|
|
| 39. |
|
|
| 40. |
|
|
| 41. |
- Hosia, W., et al.
(author)
-
Folding into a ß-Hairpin Can Prevent Amyloid Fibril-Formation
- 2004
-
In: Biochemistry. - : American Chemical Society (ACS). - 0006-2960 .- 1520-4995. ; 43:16, s. 4655-4661
-
Journal article (peer-reviewed)abstract
- The tetrapeptide KFFE is one of the shortest amyloid fibril-forming peptides described. Herein, we have investigated how the structural environment of this motif affects polymerization. Using a turn motif (YNGK) or a less rigid sequence (AAAK) to fuse two KFFE tetrapeptides, we show by several biophysical methods that the amyloidogenic properties are strongly dependent on the structural environment. The dodecapeptide KFFEAAAKKFFE forms abundant thick fibril bundles. Freshly dissolved KFFEAAAKKFFE is monomeric and shows mainly disordered secondary structure, as evidenced by circular dichroism, NMR spectroscopy, hydrogen/deuterium exchange measurements, and molecular modeling studies. In sharp contrast, the dodecapeptide KFFEYNGKKFFE does not form fibrils but folds into a stable ß-hairpin. This structure can oligomerize into a stable 12-mer and multiples thereof, as shown by size exclusion chromatography, sedimentation analysis, and electrospray mass spectrometry. These data indicate that the structural context in which a potential fibril forming sequence is present can prevent fibril formation by favoring self-limiting oligomerization over polymerization.
|
|
| 42. |
|
|
| 43. |
|
|
| 44. |
- Johansson, Birgitta, et al.
(author)
-
Health-related quality of life and distress in cancer patients : results from a large randomised study
- 2008
-
In: British Journal of Cancer. - : Springer Science and Business Media LLC. - 0007-0920 .- 1532-1827. ; 99:12, s. 1975-1983
-
Journal article (peer-reviewed)abstract
- To compare the effectiveness of individual support, group rehabilitation and a combination of the two in improving health-related quality of life (HRQOL) and psychological well-being in cancer patients during 24 months after diagnosis, as compared with standard care (SC). Furthermore, to compare the study sample and a random sample of the Swedish population with regard to HRQOL. A total of 481 consecutive patients, newly diagnosed with cancer, were randomly assigned to one of the four alternatives. Data on HRQOL and psychological well-being were collected at baseline and after 3, 6, 12 and 24 months. The interventions did not improve HRQOL or psychological well-being, as compared with SC. At 3 months, the study sample reported an HRQOL comparable with the normal population. Many cancer patients are able to manage their cancer-related concerns with the support available from SC. However, it is reasonable to assume that the findings suffer from a lack of data from especially vulnerable patients and a possible Hawthorne effect. It cannot be concluded that cancer patients have no need for additional psychosocial interventions. Future projects should include screening and target interventions for those at risk for significant and prolonged psychological distress.
|
|
| 45. |
- Johri, Atul K., et al.
(author)
-
Fungal association and utilization of phosphate by plants : success, limitations, and future prospects
- 2015
-
In: Frontiers in Microbiology. - : Frontiers Media SA. - 1664-302X. ; 6
-
Research review (peer-reviewed)abstract
- Phosphorus (P) is a major macronutrient for plant health and development. The available form of P is generally low in the rhizosphere even in fertile soils. A major proportion of applied phosphate (Pi) fertilizers in the soil become fixed into insoluble, unavailable forms, which restricts crop production throughout the world. Roots possess two distinct modes of P uptake from the soil, direct and indirect uptake. The direct uptake of P is facilitated by the plant's own Pi transporters while indirect uptake occurs via mycorrhizal symbiosis, where the host plant obtains P primarily from the fungal partner, while the fungus benefits from plant-derived reduced carbon. So far, only one Pi transporter has been characterized from the mycorrhizal fungus Glomus versiforme. As arbuscular mycorrhizal fungi cannot be cultured axenically, their Pi transporter network is difficult to exploite for large scale sustainable agriculture. Alternatively, the root-colonizing endophytic fungus Piriformospora indica can grow axenically and provides strong growth-promoting activity during its symbiosis with a broad spectrum of plants. P indica contains a high affinity Pi transporter (PiPT) involved in improving Pi nutrition levels in the host plant under P limiting conditions. As P indica can be manipulated genetically, it opens new vistas to be used in P deficient fields.
|
|
| 46. |
- Kavanagh, K L, et al.
(author)
-
The SDR superfamily : functional and structural diversity within a family of metabolic and regulatory enzymes
- 2008
-
In: Cellular and Molecular Life Sciences (CMLS). - : Springer Science and Business Media LLC. - 1420-682X .- 1420-9071. ; 65:24, s. 3895-3906
-
Journal article (peer-reviewed)abstract
- Short-chain dehydrogenases/reductases (SDRs) constitute a large family of NAD(P)(H)-dependent oxidoreductases, sharing sequence motifs and displaying similar mechanisms. SDR enzymes have critical roles in lipid, amino acid, carbohydrate, cofactor, hormone and xenobiotic metabolism as well as in redox sensor mechanisms. Sequence identities are low, and the most conserved feature is an alpha/beta folding pattern with a central beta sheet flanked by 2 - 3 alpha-helices from each side, thus a classical Rossmannfold motif for nucleotide binding. The conservation of this element and an active site, often with an Asn-Ser-Tyr-Lys tetrad, provides a platform for enzymatic activities encompassing several EC classes, including oxidoreductases, epimerases and lyases. The common mechanism is an underlying hydride and proton transfer involving the nicotinamide and typically an active site tyrosine residue, whereas substrate specificity is determined by a variable C-terminal segment. Relationships exist with bacterial haloalcohol dehalogenases, which lack cofactor binding but have the active site architecture, emphasizing the versatility of the basic fold in also generating hydride transfer-independent lyases. The conserved fold and nucleotide binding emphasize the role of SDRs as scaffolds for an NAD(P)(H) redox sensor system, of importance to control metabolic routes, transcription and signalling.
|
|
| 47. |
|
|
| 48. |
- Lagerstedt, Jens, 1975-
(author)
-
Regulatory and Structural Properties of the High-Affinity Phosphate Acquisition System in Saccharomyces cerevisiae
- 2004
-
Doctoral thesis (other academic/artistic)abstract
- Inorganic phosphate is an essential nutrient required for the synthesis of many cellular components (e.g., nucleic acids, proteins, lipids and sugars), as well as for meeting metabolic needs (e.g., energy production and translocation). In the case of the unicellular yeast Saccharomyces cerevisiae, the presence of both high- and low-affinity phosphate transporters in the plasma membrane provides for adaptation to environmental variations. Of these systems, the high-affinity Pho84 transport system is the major phosphate transporter activated when the cells have limited access to external phosphate. This integral membrane protein belongs to the major facilitator superfamily (MFS) and possesses 12 predicted transmembrane domains. Activation of this and other proteins (e.g., extracellular phosphatases) involved in maintaining cellular phosphate homeostasis under conditions of limited availability of external phosphate is controlled primarily by transcriptional regulation. However, the presence of proteins indirectly or directly involved in phosphate transport by Pho84, including Gtr1, has been reported. The Gtr1 protein binds guanine nucleotides and probably functions as a molecular switch. The present thesis describes the regulated intracellular trafficking and degradation of Pho84 in response to phosphate, as well as to its non-hydrolysable and non-utilizable analog methylphosphonate. The involvement of the Gtr1 protein in high-affinity phosphate uptake has also been examined. Moreover, in vitro and in silico analyses of structural and functional aspects of both the Pho84 and Gtr1 proteins are presented and discussed.
|
|
| 49. |
|
|
| 50. |
- Lavebratt, C., et al.
(author)
-
Association study between chromosome 10q26.11 and obesity among Swedish men
- 2005
-
In: International Journal of Obesity. - : Springer Science and Business Media LLC. - 0307-0565 .- 1476-5497. ; 29:12, s. 1422-1428
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: Proximal chromosome 10q26 was recently linked to waist/hip ratio in European and African-American families. The objective was to investigate whether genomic variation in chromosome 10q26.11 reflects variation in obesity-related clinical parameters in a Swedish population. DESIGN: Genetic association study of single-nucleotide polymorphisms (SNPs) in chromosome 10q26.11 and obesity-related clinical parameters was performed. Obesity was defined as body mass index (BMI)≥30 kg/m2. SUBJECTS: Swedish Caucasians comprising 276 obese and 480 nonobese men, 313 obese and 494 nonobese women, 177 obese and 163 nonobese patients with type 2 diabetes mellitus (T2DM), and 106 obese and 201 nonobese subjects with impaired glucose tolerance (IGT) patients. MEASUREMENTS: Genotypes of 11 SNPs at chromosome 10q26.11, and various obesity-related clinical parameters. RESULTS: Homozygosity of a common haplotype constructed by three SNPs, rs2185937, rs1797 and hCV1402327, covering an interval of 2.7 kb, was suggested to confer an increased risk for obesity of 1.5 among men (P=0.043). The C allele frequency and homozygous genotype frequency of the rs1797 tended to be higher among obese compared to among nonobese men (P=0.017 and 0.020, respectively). The distribution of BMI and diastolic blood pressure was higher among those with the C/C genotype (P=0.022 and 0.0061, respectively). The obese and the nonobese groups were homogeneous over BMI subgroups with regard to rs1797 risk genotype distribution. There was no tendency for association between rs1797 and obesity among neither women nor T2DM nor IGT patients. CONCLUSION: We show support for association between proximal chromosome 10q26.11 and obesity among Swedish men but not women through the analysis of a haplotype encompassing 2.7 kb. © 2005 Nature Publishing Group All rights reserved.
|
|
