Development of a gene inactivation system for Bacteroides forsythus: Construction and characterization of a BspA mutant

Bacteroides forsythus is a gram-negative anaerobic bacterium associated wit h periodontitis. The bspA gene encoding a cell surface associated leucine-r ich repeat protein (BspA) involved in adhesion to fibronectin and fibrinoge n was recently cloned from this bacterium in our laboratory. We now describ e the construction of a BspA-defective mutant of B, forsythus. This is the first report describing the generation of a specific gene knockout mutant o f B. forsythus, and this procedure should be useful in establishing the ide ntity of virulence-associated factors in these organisms.