The identification of response regulators of Branhamella catarrhalis usingPCR

Potential response regulator gene fragments from the genome of Branhamella Moraxella catarrhalis were isolated by PCR using degenerate oligonucleotide primers. DNA sequence analysis of several cloned PCR products with similar restriction endonuclease analysis (REA) patterns revealed that the cloned gene fragment had significant homology to members of the OMPR sub-family of response regulator genes, including 61% identity with the phoB gene of Hae mophilus influenzae. The derived amino acid sequence showed greatest simila rity to the PhoB response regulator protein of Pseudomonas aeruginosa. Char acterisation of this phoB homologue and of other response regulators identi fied in this study should provide new knowledge of the physiology and patho genic mechanisms of B. catarrhalis. (C) 1998 Federation of European Microbi ological Societies. Published by Elsevier Science B.V. All rights reserved.