Dataset Information

Identification of cholix toxin gene in Vibrio cholerae non-O1/non-O139 isolated from diarrhea patients in Bushehr, Iran.

ABSTRACT:

Background and objectives

Cholixin (cholix toxin) is a novel exotoxin in Vibrio cholerae identified as an elongation factor II specific ADP-ribosyltransferase which inhibits protein synthesis in the eukaryotic cell. Previous researches have suggested that cholixin probably is an important virulence factor in non-O1/non-O139 V. cholerae (NAG) serotypes that could be related to extra-intestinal rather than intestinal infections. This study was aimed to investigate the frequency and genetic diversity of colixin gene (chxA) in clinical V. cholerae NAG isolates.

Materials and methods

The presence of chxA gene in 44 clinical V. cholerae NAG isolates were screened using PCR through specific primers designed for the receptor-binding domain (RBD) of chxA gene. The five PCR products of chxA gene were sequenced.

Results

This study showed that chxA gene presented in 19 V. cholerae NAG isolates. The sequences analysis of 5 out of 19 the partial chxA genes amplicon showed that 4 of them belonged to chxA I and the other one belonged to chxA II subtypes. Two distinct clusters were revealed for these isolates by phylogenic analysis, too.

Conclusion

The chxA gene contained high frequency among V. cholerae NAG isolates in Bushehr, Iran. The polymorphism study on RBD of cholixin gene is suggested as an appropriate method for phylogenic characterization of the various chxA gene subtypes.

SUBMITTER: Tangestani MG

PROVIDER: S-EPMC7502140 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Identification of cholix toxin gene in <i>Vibrio cholerae</i> non-O1/non-O139 isolated from diarrhea patients in Bushehr, Iran.

Tangestani Marziyeh Gholizadeh MG Alinezhad Jafar J Khajeian Abdolmohammad A Gharibi Somayyeh S Haghighi Mohammad Ali MA

Iranian journal of microbiology 20200801 4

<h4>Background and objectives</h4>Cholixin (cholix toxin) is a novel exotoxin in <i>Vibrio cholerae</i> identified as an elongation factor II specific ADP-ribosyltransferase which inhibits protein synthesis in the eukaryotic cell. Previous researches have suggested that cholixin probably is an important virulence factor in non-O1/non-O139 <i>V. cholerae</i> (NAG) serotypes that could be related to extra-intestinal rather than intestinal infections. This study was aimed to investigate the frequen ...[more]

PMID: 32994897

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