Surveillance and Genomics of Toxigenic Vibrio cholerae O1 From Fish, Phytoplankton and Water in Lake Victoria, Tanzania
The occurrence of toxigenic Vibrio cholerae O1 during a non- outbreak period in Lake Victoria was studied and genetic characteristics for environmental persistence and relatedness to pandemic strains were assessed. We analyzed 360 samples of carps, phytoplankton and water collected in 2017 during dr...
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Frontiers Media S.A.
2019-04-01
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Series: | Frontiers in Microbiology |
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Online Access: | https://www.frontiersin.org/article/10.3389/fmicb.2019.00901/full |
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DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Yaovi M. Gildas Hounmanou Pimlapas Leekitcharoenphon Rene S. Hendriksen Tamegnon V. Dougnon Robinson H. Mdegela John E. Olsen Anders Dalsgaard |
spellingShingle |
Yaovi M. Gildas Hounmanou Pimlapas Leekitcharoenphon Rene S. Hendriksen Tamegnon V. Dougnon Robinson H. Mdegela John E. Olsen Anders Dalsgaard Surveillance and Genomics of Toxigenic Vibrio cholerae O1 From Fish, Phytoplankton and Water in Lake Victoria, Tanzania Frontiers in Microbiology Vibrio cholerae genomics aquatic reservoirs African Great Lakes microbial ecology |
author_facet |
Yaovi M. Gildas Hounmanou Pimlapas Leekitcharoenphon Rene S. Hendriksen Tamegnon V. Dougnon Robinson H. Mdegela John E. Olsen Anders Dalsgaard |
author_sort |
Yaovi M. Gildas Hounmanou |
title |
Surveillance and Genomics of Toxigenic Vibrio cholerae O1 From Fish, Phytoplankton and Water in Lake Victoria, Tanzania |
title_short |
Surveillance and Genomics of Toxigenic Vibrio cholerae O1 From Fish, Phytoplankton and Water in Lake Victoria, Tanzania |
title_full |
Surveillance and Genomics of Toxigenic Vibrio cholerae O1 From Fish, Phytoplankton and Water in Lake Victoria, Tanzania |
title_fullStr |
Surveillance and Genomics of Toxigenic Vibrio cholerae O1 From Fish, Phytoplankton and Water in Lake Victoria, Tanzania |
title_full_unstemmed |
Surveillance and Genomics of Toxigenic Vibrio cholerae O1 From Fish, Phytoplankton and Water in Lake Victoria, Tanzania |
title_sort |
surveillance and genomics of toxigenic vibrio cholerae o1 from fish, phytoplankton and water in lake victoria, tanzania |
publisher |
Frontiers Media S.A. |
series |
Frontiers in Microbiology |
issn |
1664-302X |
publishDate |
2019-04-01 |
description |
The occurrence of toxigenic Vibrio cholerae O1 during a non- outbreak period in Lake Victoria was studied and genetic characteristics for environmental persistence and relatedness to pandemic strains were assessed. We analyzed 360 samples of carps, phytoplankton and water collected in 2017 during dry and rainy seasons in the Tanzanian basin of Lake Victoria. Samples were tested using PCR (ompW and ctxA) with DNA extracted from bacterial isolates and samples enriched in alkaline peptone water. Isolates were screened with polyvalent antiserum O1 followed by antimicrobial susceptibility testing. Whole genome sequencing and bioinformatics tools were employed to investigate the genomic characteristics of the isolates. More V. cholerae positive samples were recovered by PCR when DNA was obtained from enriched samples than from isolates (69.0% vs. 21.3%, p < 0.05), irrespectively of season. We identified ten V. cholerae O1 among 22 ctxA-positive isolates. Further studies are needed to serotype the remaining ctxA-positive non-O1 strains. Sequenced strains belonged to El Tor atypical biotype of V. cholerae O1 of MLST ST69 harboring the seventh pandemic gene. Major virulence genes, ctxA, ctxB, zot, ace, tcpA, hlyA, rtxA, ompU, toxR, T6SS, alsD, makA and pathogenicity islands VPI-1, VPI-2, VSP-1, and VSP-2 were found in all strains. The strains contained Vibrio polysaccharide biosynthesis enzymes, the mshA gene and two-component response regulator proteins involved in stress response and autoinducers for quorum sensing and biofilm formation. They carried the SXT integrative conjugative element with phenotypic and genotypic resistance to aminoglycoside, sulfamethoxazole, trimethoprim, phenicol, and quinolones. Strains contained a multidrug efflux pump component and were resistant to toxic compounds with copper homeostasis and cobalt-zinc-cadmium resistance proteins. The environmental strains belonged to the third wave of the seventh pandemic and most are genetically closely related to recent outbreak strains from Tanzania, Kenya, and Uganda with as low as three SNPs difference. Some strains have persisted longer in the environment and were more related to older outbreak strains in the region. V. cholerae O1 of outbreak potential seem to persist in Lake Victoria through interactions with fish and phytoplankton supported by the optimum water parameters and intrinsic genetic features enhancing survival in the aquatic environment. |
topic |
Vibrio cholerae genomics aquatic reservoirs African Great Lakes microbial ecology |
url |
https://www.frontiersin.org/article/10.3389/fmicb.2019.00901/full |
work_keys_str_mv |
AT yaovimgildashounmanou surveillanceandgenomicsoftoxigenicvibriocholeraeo1fromfishphytoplanktonandwaterinlakevictoriatanzania AT pimlapasleekitcharoenphon surveillanceandgenomicsoftoxigenicvibriocholeraeo1fromfishphytoplanktonandwaterinlakevictoriatanzania AT reneshendriksen surveillanceandgenomicsoftoxigenicvibriocholeraeo1fromfishphytoplanktonandwaterinlakevictoriatanzania AT tamegnonvdougnon surveillanceandgenomicsoftoxigenicvibriocholeraeo1fromfishphytoplanktonandwaterinlakevictoriatanzania AT robinsonhmdegela surveillanceandgenomicsoftoxigenicvibriocholeraeo1fromfishphytoplanktonandwaterinlakevictoriatanzania AT johneolsen surveillanceandgenomicsoftoxigenicvibriocholeraeo1fromfishphytoplanktonandwaterinlakevictoriatanzania AT andersdalsgaard surveillanceandgenomicsoftoxigenicvibriocholeraeo1fromfishphytoplanktonandwaterinlakevictoriatanzania |
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doaj-da6747d7c56848629c24b819c5d3fee72020-11-25T01:34:39ZengFrontiers Media S.A.Frontiers in Microbiology1664-302X2019-04-011010.3389/fmicb.2019.00901446838Surveillance and Genomics of Toxigenic Vibrio cholerae O1 From Fish, Phytoplankton and Water in Lake Victoria, TanzaniaYaovi M. Gildas Hounmanou0Pimlapas Leekitcharoenphon1Rene S. Hendriksen2Tamegnon V. Dougnon3Robinson H. Mdegela4John E. Olsen5Anders Dalsgaard6Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, DenmarkNational Food Institute, WHO Collaborating Center for Antimicrobial Resistance in Food Borne Pathogens and Genomics and European Union Reference Laboratory for Antimicrobial Resistance, Technical University of Denmark, Kongens Lyngby, DenmarkNational Food Institute, WHO Collaborating Center for Antimicrobial Resistance in Food Borne Pathogens and Genomics and European Union Reference Laboratory for Antimicrobial Resistance, Technical University of Denmark, Kongens Lyngby, DenmarkResearch Unit in Applied Microbiology and Pharmacology of Natural Substances, Laboratory of Research in Applied Biology, Polytechnic School of Abomey-Calavi, University of Abomey-Calavi, Cotonou, BeninDepartment of Veterinary Medicine and Public Health, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, TanzaniaDepartment of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, DenmarkDepartment of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, DenmarkThe occurrence of toxigenic Vibrio cholerae O1 during a non- outbreak period in Lake Victoria was studied and genetic characteristics for environmental persistence and relatedness to pandemic strains were assessed. We analyzed 360 samples of carps, phytoplankton and water collected in 2017 during dry and rainy seasons in the Tanzanian basin of Lake Victoria. Samples were tested using PCR (ompW and ctxA) with DNA extracted from bacterial isolates and samples enriched in alkaline peptone water. Isolates were screened with polyvalent antiserum O1 followed by antimicrobial susceptibility testing. Whole genome sequencing and bioinformatics tools were employed to investigate the genomic characteristics of the isolates. More V. cholerae positive samples were recovered by PCR when DNA was obtained from enriched samples than from isolates (69.0% vs. 21.3%, p < 0.05), irrespectively of season. We identified ten V. cholerae O1 among 22 ctxA-positive isolates. Further studies are needed to serotype the remaining ctxA-positive non-O1 strains. Sequenced strains belonged to El Tor atypical biotype of V. cholerae O1 of MLST ST69 harboring the seventh pandemic gene. Major virulence genes, ctxA, ctxB, zot, ace, tcpA, hlyA, rtxA, ompU, toxR, T6SS, alsD, makA and pathogenicity islands VPI-1, VPI-2, VSP-1, and VSP-2 were found in all strains. The strains contained Vibrio polysaccharide biosynthesis enzymes, the mshA gene and two-component response regulator proteins involved in stress response and autoinducers for quorum sensing and biofilm formation. They carried the SXT integrative conjugative element with phenotypic and genotypic resistance to aminoglycoside, sulfamethoxazole, trimethoprim, phenicol, and quinolones. Strains contained a multidrug efflux pump component and were resistant to toxic compounds with copper homeostasis and cobalt-zinc-cadmium resistance proteins. The environmental strains belonged to the third wave of the seventh pandemic and most are genetically closely related to recent outbreak strains from Tanzania, Kenya, and Uganda with as low as three SNPs difference. Some strains have persisted longer in the environment and were more related to older outbreak strains in the region. V. cholerae O1 of outbreak potential seem to persist in Lake Victoria through interactions with fish and phytoplankton supported by the optimum water parameters and intrinsic genetic features enhancing survival in the aquatic environment.https://www.frontiersin.org/article/10.3389/fmicb.2019.00901/fullVibrio choleraegenomicsaquatic reservoirsAfrican Great Lakesmicrobial ecology |