title: Genetic relatedness of clinical and environmental Vibrio cholerae isolates based on triple housekeeping gene analysis.
abstract: Sequence analysis of dnaE, hlyA, and asd housekeeping genes were used to determine the genetic relatedness of our collection of Vibrio cholerae isolated from patients and surface waters over a 5-year period in Iran. The results showed 41, 17, and 9 variable sites throughout the sequenced fragments of dnaE (837 bp), hlyA (495 bp), and asd (295 bp), respectively. The results from sequence typing showed that all our clinical isolates were grouped in the same cluster. Eleven genotypes were identified among the environmental isolates. One environmental isolate was found to be in close genetic relatedness with our clinical isolates. One V. cholerae isolate showed a single-locus variant in the dnaE. For each of the studied genetic loci 10, 7, and 7 sequence types were observed for dnaE, hlyA, and asd, respectively. Only asd sequence analysis could make the distinction between the classical and El Tor isolates which emphasizes on selection of housekeeping locus with better discrimination power for analysis of different groups of isolates. Overall, the results indicated that surface waters in Tehran are a pool of non-toxigenic V. cholerae strains which are rarely related to clinical toxigenic isolates. In addition, our results verified that housekeeping gene sequence analysis could be a suitable approach for determination of the relatedness between clinical and environmental V. cholerae isolates.
authors: Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran.
authors: Abolfazl
authors: A
authors: Dashtbani-Roozbehani
authors: Bita
authors: B
authors: Bakhshi
authors: Mohammad Reza
authors: MR
authors: Pourshafie
mesh_terms: D002771:Cholera / Q000453:epidemiology / Q000382:microbiology*; D016000:Cluster Analysis; D020043:Genes, Essential; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007492:Iran / Q000453:epidemiology; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D017422:Sequence Analysis, DNA; D014734:Vibrio cholerae / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D014871:Water Microbiology
references: Infect Immun. 1999 Mar;67(3):1116-24
references: 10024551
references: J Bacteriol. 1995 Jun;177(11):3191-8
references: 7768818
references: Appl Environ Microbiol. 2005 Sep;71(9):5107-15
references: 16151093
references: Philos Trans R Soc Lond B Biol Sci. 1999 Apr 29;354(1384):701-10
references: 10365396
references: Emerg Infect Dis. 2003 Jul;9(7):810-4
references: 12890320
references: FEMS Microbiol Lett. 2008 Nov;288(2):196-201
references: 18811655
references: Microbiology (Reading). 2007 May;153(Pt 5):1488-1498
references: 17464063
references: Scand J Infect Dis. 2009;41(4):256-62
references: 19253091
references: Appl Environ Microbiol. 2001 Feb;67(2):910-21
references: 11157262
references: Water Res. 2009 Mar;43(5):1441-7
references: 19157484
references: Genetics. 2000 Apr;154(4):1439-50
references: 10747043
references: J Clin Microbiol. 1994 Jul;32(7):1685-90
references: 7929758
references: Appl Environ Microbiol. 1999 May;65(5):2202-8
references: 10224020
references: J Med Microbiol. 1997 Nov;46(11):941-8
references: 9368535
references: J Clin Microbiol. 1993 Sep;31(9):2474-82
references: 7691876
references: Res Microbiol. 2009 Jan-Feb;160(1):57-62
references: 19028569
references: Lett Appl Microbiol. 2011 Sep;53(3):313-23
references: 21707677
references: J Bacteriol. 2002 Mar;184(5):1304-13
references: 11844759
references: Iran Biomed J. 2008 Jul;12(3):159-65
references: 18762819
references: J Clin Microbiol. 2004 Oct;42(10):4657-71
references: 15472325
references: Microbiology (Reading). 2000 Oct;146 ( Pt 10):2613-2626
references: 11021936
references: Mol Biol Evol. 2007 Aug;24(8):1596-9
references: 17488738
references: Nature. 2000 Aug 3;406(6795):477-83
references: 10952301