Aneley Getahun Strobel, Andrew J. Hayes, Wytamma Wirth, Mikaele Mua, Tiko Saumalua, Orisi Cabenatabua, Vika Soqo, Varanisese Rosa, Nancy Wang, Jake A. Lacey, Dianna Hocking, Mary Valcanis, Adam Jenney, Benjamin P. Howden, Sebastian Duchene, Kim Mulholland, Richard A. Strugnell and Mark R. Davies
{"title":"伤寒沙门氏菌 Vi 胶囊位点的遗传异质性:斐济群体基因组研究","authors":"Aneley Getahun Strobel, Andrew J. Hayes, Wytamma Wirth, Mikaele Mua, Tiko Saumalua, Orisi Cabenatabua, Vika Soqo, Varanisese Rosa, Nancy Wang, Jake A. Lacey, Dianna Hocking, Mary Valcanis, Adam Jenney, Benjamin P. Howden, Sebastian Duchene, Kim Mulholland, Richard A. Strugnell and Mark R. Davies","doi":"10.1099/mgen.0.001288","DOIUrl":null,"url":null,"abstract":"Typhoid fever is endemic in many parts of the world and remains a major public health concern in tropical and sub-tropical developing nations, including Fiji. To address high rates of typhoid fever, the Northern Division of Fiji implemented a mass vaccination with typhoid conjugate vaccine (Vi-polysaccharide conjugated to tetanus toxoid) as a public health control measure in 2023. In this study we define the genomic epidemiology of <span>Salmonella</span> Typhi in the Northern Division prior to island-wide vaccination, sequencing 85% (<span>n</span>=419) of the total cases from the Northern and Central Divisions of Fiji that occurred in the period 2017–2019. We found elevated rates of nucleotide polymorphisms in the <span>tviD</span> and <span>tviE</span> genes (responsible for Vi-polysaccharide synthesis) relative to core genome levels within the Fiji endemic <span>S</span>. Typhi genotype 4.2. Expansion of these findings within a globally representative database of 12 382 <span>S</span>. Typhi (86 genotyphi clusters) showed evidence of convergent evolution of the same <span>tviE</span> mutations across the <span>S</span>. Typhi population, indicating that <span>tvi</span> selection has occurred both independently and globally. The functional impact of <span>tvi</span> mutations on the Vi-capsular structure and other phenotypic characteristics are not fully elucidated, yet commonly occurring <span>tviE</span> polymorphisms localize adjacent to predicted active site residues when overlayed against the predicted TviE protein structure. Given the central role of the Vi-polysaccharide in <span>S</span>. Typhi biology and vaccination, further integrated epidemiological, genomic and phenotypic surveillance is required to determine the spread and functional implications of these mutations.","PeriodicalId":18487,"journal":{"name":"Microbial Genomics","volume":null,"pages":null},"PeriodicalIF":4.0000,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Genetic heterogeneity in the Salmonella Typhi Vi capsule locus: a population genomic study from Fiji\",\"authors\":\"Aneley Getahun Strobel, Andrew J. Hayes, Wytamma Wirth, Mikaele Mua, Tiko Saumalua, Orisi Cabenatabua, Vika Soqo, Varanisese Rosa, Nancy Wang, Jake A. Lacey, Dianna Hocking, Mary Valcanis, Adam Jenney, Benjamin P. Howden, Sebastian Duchene, Kim Mulholland, Richard A. Strugnell and Mark R. Davies\",\"doi\":\"10.1099/mgen.0.001288\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Typhoid fever is endemic in many parts of the world and remains a major public health concern in tropical and sub-tropical developing nations, including Fiji. To address high rates of typhoid fever, the Northern Division of Fiji implemented a mass vaccination with typhoid conjugate vaccine (Vi-polysaccharide conjugated to tetanus toxoid) as a public health control measure in 2023. In this study we define the genomic epidemiology of <span>Salmonella</span> Typhi in the Northern Division prior to island-wide vaccination, sequencing 85% (<span>n</span>=419) of the total cases from the Northern and Central Divisions of Fiji that occurred in the period 2017–2019. We found elevated rates of nucleotide polymorphisms in the <span>tviD</span> and <span>tviE</span> genes (responsible for Vi-polysaccharide synthesis) relative to core genome levels within the Fiji endemic <span>S</span>. Typhi genotype 4.2. Expansion of these findings within a globally representative database of 12 382 <span>S</span>. Typhi (86 genotyphi clusters) showed evidence of convergent evolution of the same <span>tviE</span> mutations across the <span>S</span>. Typhi population, indicating that <span>tvi</span> selection has occurred both independently and globally. The functional impact of <span>tvi</span> mutations on the Vi-capsular structure and other phenotypic characteristics are not fully elucidated, yet commonly occurring <span>tviE</span> polymorphisms localize adjacent to predicted active site residues when overlayed against the predicted TviE protein structure. Given the central role of the Vi-polysaccharide in <span>S</span>. Typhi biology and vaccination, further integrated epidemiological, genomic and phenotypic surveillance is required to determine the spread and functional implications of these mutations.\",\"PeriodicalId\":18487,\"journal\":{\"name\":\"Microbial Genomics\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.0000,\"publicationDate\":\"2024-09-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Microbial Genomics\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://doi.org/10.1099/mgen.0.001288\",\"RegionNum\":2,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"GENETICS & HEREDITY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Microbial Genomics","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1099/mgen.0.001288","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GENETICS & HEREDITY","Score":null,"Total":0}
Genetic heterogeneity in the Salmonella Typhi Vi capsule locus: a population genomic study from Fiji
Typhoid fever is endemic in many parts of the world and remains a major public health concern in tropical and sub-tropical developing nations, including Fiji. To address high rates of typhoid fever, the Northern Division of Fiji implemented a mass vaccination with typhoid conjugate vaccine (Vi-polysaccharide conjugated to tetanus toxoid) as a public health control measure in 2023. In this study we define the genomic epidemiology of Salmonella Typhi in the Northern Division prior to island-wide vaccination, sequencing 85% (n=419) of the total cases from the Northern and Central Divisions of Fiji that occurred in the period 2017–2019. We found elevated rates of nucleotide polymorphisms in the tviD and tviE genes (responsible for Vi-polysaccharide synthesis) relative to core genome levels within the Fiji endemic S. Typhi genotype 4.2. Expansion of these findings within a globally representative database of 12 382 S. Typhi (86 genotyphi clusters) showed evidence of convergent evolution of the same tviE mutations across the S. Typhi population, indicating that tvi selection has occurred both independently and globally. The functional impact of tvi mutations on the Vi-capsular structure and other phenotypic characteristics are not fully elucidated, yet commonly occurring tviE polymorphisms localize adjacent to predicted active site residues when overlayed against the predicted TviE protein structure. Given the central role of the Vi-polysaccharide in S. Typhi biology and vaccination, further integrated epidemiological, genomic and phenotypic surveillance is required to determine the spread and functional implications of these mutations.
期刊介绍:
Microbial Genomics (MGen) is a fully open access, mandatory open data and peer-reviewed journal publishing high-profile original research on archaea, bacteria, microbial eukaryotes and viruses.