1.
Jakobsson, Hedvig E, et al.
(författare)
Draft Genome Sequence of Moraxella catarrhalis Type Strain CCUG 353T.
2016
Ingår i: Genome Announcements. - 2169-8287. ; 4:3
Tidskriftsartikel (refereegranskat) abstract
Moraxella catarrhalis is a Gram-negative commensal and pathogenic bacterium found in the human respiratory tract. It is associated with otitis media and respiratory tract infections. Here, we report the draft genome sequence of M. catarrhalis type strain CCUG 353(T), composed of 18 contigs and a total size of 1.89 Mb.
2.
Salvà-Serra, Francisco, 1989, et al.
(författare)
Draft Genome Sequence of Streptococcus gordonii Type Strain CCUG 33482T.
2016
Ingår i: Genome Announcements. - 2169-8287. ; 4:2
Tidskriftsartikel (refereegranskat) abstract
Streptococcus gordoniitype strain CCUG 33482(T)is a member of theStreptococcus mitisgroup, isolated from a case of subacute bacterial endocarditis. Here, we report the draft genome sequence ofS. gordoniiCCUG 33482(T), composed of 41 contigs of a total size of 2.15 Mb with 2,061 annotated coding sequences.
3.
Abrahamsson, Thomas, et al.
(författare)
Low gut microbiota diversity in early infancy precedes asthma at school age
2014
Ingår i: Clinical and Experimental Allergy. - : Wiley. - 0954-7894 .- 1365-2222. ; 44:6, s. 842-850
Tidskriftsartikel (refereegranskat) abstract
Background Low total diversity of the gut microbiota during the first year of life is associated with allergic diseases in infancy, but little is known how early microbial diversity is related to allergic disease later in school age. Objective To assess microbial diversity and characterize the dominant bacteria in stool during the first year of life in relation to the prevalence of different allergic diseases in school age, such as asthma, allergic rhinoconjunctivitis (ARC) and eczema. Methods The microbial diversity and composition was analysed with barcoded 16S rDNA 454 pyrosequencing in stool samples at 1week, 1month and 12months of age in 47 infants which were subsequently assessed for allergic disease and skin prick test reactivity at 7years of age (ClinicalTrials.gov ID NCT01285830). Results Children developing asthma (n=8) had a lower diversity of the total microbiota than non-asthmatic children at 1week (P=0.04) and 1month (P=0.003) of age, whereas allergic rhinoconjunctivitis (n=13), eczema (n=12) and positive skin prick reactivity (n=14) at 7years of age did not associate with the gut microbiota diversity. Neither was asthma associated with the microbiota composition later in infancy (at 12months). Children having IgE-associated eczema in infancy and subsequently developing asthma had lower microbial diversity than those that did not. There were no significant differences, however, in relative abundance of bacterial phyla and genera between children with or without allergic disease. Conclusion and Clinical Relevance Low total diversity of the gut microbiota during the first month of life was associated with asthma but not ARC in children at 7years of age. Measures affecting microbial colonization of the infant during the first month of life may impact asthma development in childhood.
4.
Åberg, Anna, et al.
(författare)
Helicobacter pylori adapts to chronic infection and gastric disease via ph-responsive baba-mediated adherence
2017
Ingår i: Cell Host and Microbe. - : Elsevier BV. - 1931-3128 .- 1934-6069. ; 21:3, s. 376-389
Tidskriftsartikel (refereegranskat) abstract
The BabA adhesin mediates high-affinity binding of Helicobacter pylori to the ABO blood group antigen-glycosylated gastric mucosa. Here we show that BabA is acid responsive-binding is reduced at low pH and restored by acid neutralization. Acid responsiveness differs among strains; often correlates with different intragastric regions and evolves during chronic infection and disease progression; and depends on pH sensor sequences in BabA and on pH reversible formation of high-affinity binding BabA multimers. We propose that BabA's extraordinary reversible acid responsiveness enables tight mucosal bacterial adherence while also allowing an effective escape from epithelial cells and mucus that are shed into the acidic bactericidal lumen and that bio-selection and changes in BabA binding properties through mutation and recombination with babA-related genes are selected by differences among individuals and by changes in gastric acidity over time. These processes generate diverse H. pylori subpopulations, in which BabA's adaptive evolution contributes to H. pylori persistence and overt gastric disease.
5.
Abdellah, Tebani, et al.
(författare)
Integration of molecular profiles in a longitudinal wellness profiling cohort.
2020
Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 11:1
Tidskriftsartikel (refereegranskat) abstract
An important aspect of precision medicine is to probe the stability in molecular profiles among healthy individuals over time. Here, we sample a longitudinal wellness cohort with 100 healthy individuals and analyze blood molecular profiles including proteomics, transcriptomics, lipidomics, metabolomics, autoantibodies and immune cell profiling, complemented with gut microbiota composition and routine clinical chemistry. Overall, our results show high variation between individuals across different molecular readouts, while the intra-individual baseline variation is low. The analyses show that each individual has a unique and stable plasma protein profile throughout the study period and that many individuals also show distinct profiles with regards to the other omics datasets, with strong underlying connections between the blood proteome and the clinical chemistry parameters. In conclusion, the results support an individual-based definition of health and show that comprehensive omics profiling in a longitudinal manner is a path forward for precision medicine.
6.
Aspholm, Marina, et al.
(författare)
SabA is the H. pylori hemagglutinin and is polymorphic in binding to sialylated glycans.
2006
Ingår i: PLoS pathogens. - : Public Library of Science (PLoS). - 1553-7374 .- 1553-7366. ; 2:10
Tidskriftsartikel (refereegranskat) abstract
Adherence of Helicobacter pylori to inflamed gastric mucosa is dependent on the sialic acid-binding adhesin (SabA) and cognate sialylated/fucosylated glycans on the host cell surface. By in situ hybridization, H. pylori bacteria were observed in close association with erythrocytes in capillaries and post-capillary venules of the lamina propria of gastric mucosa in both infected humans and Rhesus monkeys. In vivo adherence of H. pylori to erythrocytes may require molecular mechanisms similar to the sialic acid-dependent in vitro agglutination of erythrocytes (i.e., sialic acid-dependent hemagglutination). In this context, the SabA adhesin was identified as the sialic acid-dependent hemagglutinin based on sialidase-sensitive hemagglutination, binding assays with sialylated glycoconjugates, and analysis of a series of isogenic sabA deletion mutants. The topographic presentation of binding sites for SabA on the erythrocyte membrane was mapped to gangliosides with extended core chains. However, receptor mapping revealed that the NeuAcalpha2-3Gal-disaccharide constitutes the minimal sialylated binding epitope required for SabA binding. Furthermore, clinical isolates demonstrated polymorphism in sialyl binding and complementation analysis of sabA mutants demonstrated that polymorphism in sialyl binding is an inherent property of the SabA protein itself. Gastric inflammation is associated with periodic changes in the composition of mucosal sialylation patterns. We suggest that dynamic adaptation in sialyl-binding properties during persistent infection specializes H. pylori both for individual variation in mucosal glycosylation and tropism for local areas of inflamed and/or dysplastic tissue.
7.
Berntson, Lillemor, 1957-, et al.
(författare)
A Pilot Study Investigating Faecal Microbiota After Two Dietary Interventions in Children with Juvenile Idiopathic Arthritis
2022
Ingår i: Current Microbiology. - : Springer Science and Business Media LLC. - 0343-8651 .- 1432-0991. ; 79:7
Tidskriftsartikel (refereegranskat) abstract
There is evidence for an impact of the gut microbiota on the immune system, which has consequences for inflammatory diseases. Exclusive enteral nutrition (EEN) and the specific carbohydrate diet (SCD) have been demonstrated as effective anti-inflammatory treatments for children with Crohn’s disease. We have previously shown an anti-inflammatory effect from these nutritional treatments in children with juvenile idiopathic arthritis (JIA). The aim of this study was to investigate if improved clinical symptoms after EEN or SCD treatment in children with JIA could be linked to changes in faecal microbiota. We included sixteen patients with JIA (age 7–17 years), six for treatment with EEN and ten with SCD. EEN was given for 3–5 weeks and SCD for 4–5 weeks, with clinical and laboratory status assessed before and after treatment. Faecal samples were analysed for microbiota diversity and composition using 16S rRNA gene sequencing. Analyses of the faecal microbiota showed an effect on the overall composition with both interventions; the most striking result was a decreased relative abundance of the genus Faecalibacterium from EEN and of Bifidobacterium from SCD. The α-diversity decreased significantly from SCD (P = 0.04), but not from EEN (P = 0.22). Despite the study cohorts being small, both EEN and SCD were shown to impact the faecal microbiota. Future larger studies with a focus on metagenomics or metabolomics could possibly reveal a link and clarify the clinical effects of those nutritional regimens.
8.
Berthenet, Elvire, et al.
(författare)
A GWAS on Helicobacter pylori strains points to genetic variants associated with gastric cancer risk
2018
Ingår i: BMC Biology. - : BioMed Central. - 1741-7007. ; 16:1
Tidskriftsartikel (refereegranskat) abstract
BACKGROUND:Helicobacter pylori are stomach-dwelling bacteria that are present in about 50% of the global population. Infection is asymptomatic in most cases, but it has been associated with gastritis, gastric ulcers and gastric cancer. Epidemiological evidence shows that progression to cancer depends upon the host and pathogen factors, but questions remain about why cancer phenotypes develop in a minority of infected people. Here, we use comparative genomics approaches to understand how genetic variation amongst bacterial strains influences disease progression.RESULTS:We performed a genome-wide association study (GWAS) on 173 H. pylori isolates from the European population (hpEurope) with known disease aetiology, including 49 from individuals with gastric cancer. We identified SNPs and genes that differed in frequency between isolates from patients with gastric cancer and those with gastritis. The gastric cancer phenotype was associated with the presence of babA and genes in the cag pathogenicity island, one of the major virulence determinants of H. pylori, as well as non-synonymous variations in several less well-studied genes. We devised a simple risk score based on the risk level of associated elements present, which has the potential to identify strains that are likely to cause cancer but will require refinement and validation.CONCLUSION:There are a number of challenges to applying GWAS to bacterial infections, including the difficulty of obtaining matched controls, multiple strain colonization and the possibility that causative strains may not be present when disease is detected. Our results demonstrate that bacterial factors have a sufficiently strong influence on disease progression that even a small-scale GWAS can identify them. Therefore, H. pylori GWAS can elucidate mechanistic pathways to disease and guide clinical treatment options, including for asymptomatic carriers.
9.
10.
Bugaytsova, Jeanna, et al.
(författare)
pH regulated H. pylori adherence : implications for persistent infection and disease
Annan publikation (övrigt vetenskapligt/konstnärligt) abstract
Helicobacter pylori’s BabA adhesin binds strongly to gastric mucosal ABH/Leb glycans on the stomach epithelium and overlying mucus, materials continuously shed into the acidic gastric lumen. Here we report that this binding is acid labile, acid inactivation is fully reversible; and acid lability profiles vary with BabA sequence and correlate with disease patterns. Isogenic H. pylori strains from the gastric antrum and more acidic corpus were identified that differed in acid lability of receptor binding and in sequence near BabA’s carbohydrate binding domain. We propose that reversible acid inactivation of receptor binding helps H. pylori avoid clearance by mucosal shedding, and that strain differences in acid lability affect tissue tropism and the spectrum of associated gastric diseases.
