Moraxella catarrhalis M35 is a general porin that is important for growth under nutrient-limiting conditions and in the nasopharynges of mice.

ABSTRACT: Moraxella catarrhalis is a gram-negative respiratory pathogen that is an important causative agent for otitis media and exacerbations of chronic obstructive pulmonary disease. We have previously predicted the outer membrane protein M35 to be a general porin, and in the current study, we have investigated the function of M35 and its importance for survival of M. catarrhalis in vivo. Lipid bilayer experiments reveal that refolded M35 functions as a channel that is typical of gram-negative bacterial porins. M35 forms wide and water-filled channels with a single-channel conductance of about 1.25 nS in 1 M KCl solution and has only a small selectivity for cations over anions. When the in vitro growth characteristics of two M35 deletion mutant strains of M. catarrhalis were compared to the wild-

SUBMITTER: Easton DM 

PROVIDER: S-EPMC2593229 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature