Susceptibility of fibronectin to degradation by various gram-negative and gram-positive oral micro-organisms.

The degradative effects on tritiated human plasma fibronectin (FN) of proteases associated with twenty five Gram-negative (GN) and fifteen Gram-positive (GP) oral microbial isolates were examined. Ninety-two per cent of the GN and 20% of the GP isolates degraded the FN. In the GN group, the degradative effects were greatest for Bacteroides gingivalis and Treponema denticola, while in the GP group Streptococcus faecalis produced appreciable, and the two Lactobacillus casei isolates moderate and low, levels of FN degradation.