Naturally occurring Neisseria gonorrhoeae can have large deletions in housekeeping gene abcZ, making them untypable with multilocus sequence typing

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In silico analyzes of porins involved in niche adaptation: Exploring the role of Helicobacter pylori outer membrane phospholipase A in acid tolerance.

Helicobacter pylori is an ulcer-causing bacterium that evolutionary needs to adapt quickly to changing conditions. Hilde Synnøve Vollan’s bioinformatics studies revealed that H. pylori outer membrane phospholipase A (OMPLA) is multifunctional with both enzymatic and pore activity. OMPLA is a protein found in a variety of bacterial species, and usually functions as an enzyme that degrades the outer membrane. Previous studies indicate that OMPLA must be intact for H. pylori survival in an acidic environment, while its enzymatic activity is not required. The present study presents the hypothesis that OMPLA is involved in acid management. Analyzes of the modeled H. pylori OMPLA 3D structure indicate that the niche-adaption likely is urea-influx and ammonium-efflux. This model may be paradigmatic for all gastric Helicobacter species. This work will be used in future studies aimed at preventing ulcers and gastric cancers caused by H. pylori

In Silico Structure and Sequence Analysis of Bacterial Porins and Specific Diffusion Channels for Hydrophilic Molecules: Conservation, Multimericity and Multifunctionality.

Contains fulltext : 165671.pdf (publisher's version ) (Open Access)Diffusion channels are involved in the selective uptake of nutrients and form the largest outer membrane protein (OMP) family in Gram-negative bacteria. Differences in pore size and amino acid composition contribute to the specificity. Structure-based multiple sequence alignments shed light on the structure-function relations for all eight subclasses. Entropy-variability analysis results are correlated to known structural and functional aspects, such as structural integrity, multimericity, specificity and biological niche adaptation. The high mutation rate in their surface-exposed loops is likely an important mechanism for host immune system evasion. Multiple sequence alignments for each subclass revealed conserved residue positions that are involved in substrate recognition and specificity. An analysis of monomeric protein channels revealed particular sequence patterns of amino acids that were observed in other classes at multimeric interfaces. This adds to the emerging evidence that all members of the family exist in a multimeric state. Our findings are important for understanding the role of members of this family in a wide range of bacterial processes, including bacterial food uptake, survival and adaptation mechanisms

Molecular Epidemiology of the Norwegian SARS-CoV-2 Delta Lineage AY.63

Extensive genomic surveillance has given great insights into the evolution of the SARS-CoV-2 virus and emerging variants. During the summer months of 2021, Norway was dominated by the Pango lineage AY.63 which is a sub-lineage of the highly transmissible Delta variant. Strikingly, AY.63 did not spread in other countries to any significant extent. AY.63 carried a key mutation, A222V, in the spike protein, as well as the deletion of three residues in nsp1. Although these mutations are close to functionally important areas, we did not find any evidence that they induced higher fitness compared to other Delta lineages. This variant was introduced to Norway at a time when there were low levels of SARS-CoV-2 and contact-reducing measures were relaxed, which probably explains why the lineage rose so quickly. Furthermore, we found that the lack of imports of AY.63 from other countries probably led to the eventual demise of the lineage in Norway

The impact of global lineage dynamics, border restrictions, and emergence of the B.1.1.7 lineage on the SARS-CoV-2 epidemic in Norway

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The impact of global lineage dynamics, border restrictions, and emergence of the B.1.1.7 lineage on the SARS-CoV-2 epidemic in Norway

publishedVersio