MOLECULAR-CLONING AND FUNCTIONAL-ANALYSIS OF AN RPOS HOMOLOG GENE FROM VIBRIO-CHOLERAE N86

A homologue of the rpoS gene of Escherichia coli was cloned from Vibri o cholerae N86 by complementation of the phenotypes of the E. coli rpo S mutant strain. We determined the DNA sequence of this gene. Sequence alignments have indicated that the rpoS gene of V. cholerae N86 encod ing a 39-kDa protein is very similar to that off. coli. In addition, t he nlpD-like gene was found in the upstream region of the rpoS gene in the same order as in E. coli. These results suggest that the organiza tion of these genes is highly conserved between E. coli and V. cholera e.