COMPARISON OF VIBRIO-CHOLERAE O139 WITH VIBRIO-CHOLERAE O1 CLASSICAL AND EL-TOR BIOTYPES

Vibrio cholerae O139 is a recently identified non-O1 V. cholerae strai n responsible for outbreaks of epidemic cholera in India, Bangladesh, and Thailand in the past 2 years. Other workers have demonstrated the presence of the cholera toxin genetic element in V. cholerae O139, unl ike the situation for other non-O1 V. cholerae strains. We sought to c ompare further this strain with strains of V. cholerae O1, classical a nd El Tor biotypes, by classic microbiologic methods, Southern blot an alysis for restriction fragment length polymorphisms with probes for i ron-regulated genes of V. cholerae O1, and comparisons of outer membra ne protein profiles. Our results were similar for V. cholerae O139 and the El Tor biotype of V. cholerae O1, with the exception of the const itutive expression in V. cholerae O139 of OmpS, an outer membrane prot ein that was maltose inducible in comparison strains of V. cholerae O1 .