Mechanism of drug resistance in a clinical isolate of Vibrio fluvialis: involvement of multiple plasmids and integrons.
The role of mobile genetic elements in imparting multiple drug resistance to a clinical isolate of Vibrio fluvialis (BD146) was investigated. This isolate showed complete or intermediate resistance to all of the 14 antibiotics tested. Polymerase chain reaction (PCR) revealed the presence of a class 1 integron and the absence of the SXT element in this isolate. The strain harboured a 7.5 kb plasmid and a very low copy number plasmid of unknown molecular size. Transformation of Escherichia coli with plasmid(s) from BD146 generated two kinds of transformants, one that harboured both of these plasmids and the other that harboured only the low copy number plasmid. PCR and antibiogram analysis indicated the association of the class 1 integron with the low copy number plasmid, which also conferred all the transferable resistance traits except trimethoprim to the parent strain. A BLAST search with the sequence of the 7.5kb plasmid showed that it was 99% identical to plasmid pVN84 from Vibrio cholerae O1 in Vietnam, indicating that these two plasmids are probably one and the same. To the best of our knowledge, this is the first report of horizontal transfer of a plasmid between V. fluvialis and V. cholerae.
Rajpara
Neha
N
Department of Human Health and Diseases, School of Biological Sciences and Biotechnology, Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar 382 007, Gujarat, India.
Patel
Arati
A
Tiwari
Neha
N
Bahuguna
Jyotsana
J
Antony
Anita
A
Choudhury
Ipsita
I
Ghosh
Anuradha
A
Jain
Rakesh
R
Ghosh
Amit
A
Bhardwaj
Ashima Kushwaha
AK
D000962:Antimalarials / Q000627:therapeutic use*; D002771:Cholera / Q000188:drug therapy* / Q000382:microbiology; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D022761:Gene Transfer, Horizontal; D006801:Humans; D032023:Integrons; D008826:Microbial Sensitivity Tests; D010957:Plasmids / Q000235:genetics* / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D014295:Trimethoprim / Q000627:therapeutic use; D014733:Vibrio / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification
D000962:Antimalarials; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D014295:Trimethoprim