TY - JOUR A1 - Wheeler, Nicole E. A1 - Barquist, Lars A1 - Kingsley, Robert A. A1 - Gardner, Paul P. T1 - A profile-based method for identifying functional divergence of orthologous genes in bacterial genomes JF - Bioinformatics N2 - Motivation: Next generation sequencing technologies have provided us with a wealth of information on genetic variation, but predi cting the functional significance of this variation is a difficult task. While many comparative genomics studies have focused on gene flux and large scale changes, relatively little attention has been paid to quantifying the effects of single nucleotide polymorphisms and indels on protein function, particularly in bacterial genomics. Results: We present a hidden Markov model based approach we call delta-bitscore (DBS) for identifying orthologous proteins that have diverged at the amino acid sequence level in a way that is likely to impact biological function. We benchmark this approach with several widely used datasets and apply it to a proof-of-concept study of orthologous proteomes in an investigation of host adaptation in Salmonella enterica. We highlight the value of the method in identifying functional divergence of genes, and suggest that this tool may be a better approach than the commonly used dN/dS metric for identifying functionally significant genetic changes occurring in recently diverged organisms. KW - Host adaptation KW - Salmonella-enteritidis KW - Sequence identity KW - Rapid evolution KW - Variants KW - Cystic-fibriosis KW - Strains KW - Pathogenicity KW - Typhimurium KW - Yersinia Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-186502 VL - 32 IS - 23 ER - TY - JOUR A1 - Okoro, Chinyere K. A1 - Barquist, Lars A1 - Connor, Thomas R. A1 - Harris, Simon R. A1 - Clare, Simon A1 - Stevens, Mark P. A1 - Arends, Mark J. A1 - Hale, Christine A1 - Kane, Leanne A1 - Pickard, Derek J. A1 - Hill, Jennifer A1 - Harcourt, Katherine A1 - Parkhill, Julian A1 - Dougan, Gordon A1 - Kingsley, Robert A. T1 - Signatures of adaptation in human invasive Salmonella Typhimurium ST313 populations from sub-Saharan Africa JF - PLoS Neglected Tropical Diseases N2 - Two lineages of Salmonella enterica serovar Typhimurium (S. Typhimurium) of multi-locus sequence type ST313 have been linked with the emergence of invasive Salmonella disease across sub-Saharan Africa. The expansion of these lineages has a temporal association with the HIV pandemic and antibiotic usage. We analysed the whole genome sequence of 129 ST313 isolates representative of the two lineages and found evidence of lineage-specific genome degradation, with some similarities to that observed in S. Typhi. Individual ST313 S. Typhimurium isolates exhibit a distinct metabolic signature and modified enteropathogenesis in both a murine and cattle model of colitis, compared to S. Typhimurium outside of the ST313 lineages. These data define phenotypes that distinguish ST313 isolates from other S. Typhimurium and may represent adaptation to a distinct pathogenesis and lifestyle linked to an-immuno-compromised human population. KW - genome sequence KW - infection KW - pathogenicity KW - children KW - disease KW - adults KW - identification KW - Escherichia coli KW - virulence Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-143779 VL - 9 IS - 3 ER -