Role of arginine deiminase of Streptococcus cristatus in Porphyromonas gingivalis colonization.

The ability to attach to a variety of oral surfaces is an important characteristic of Porphyromonas gingivalis. Previous studies have demonstrated that expression and production of FimA, a major subunit protein of the long fimbriae, is required for P. gingivalis colonization. Here we report that a surface protein, arginine deiminase (ArcA) of Streptococcus cristatus, represses FimA production and inhibits biofilm formation of P. gingivalis. This inhibitory function of ArcA is also observed in the formation of heterotypic P. gingivalis-Streptococcus gordonii biofilms. P. gingivalis is released from streptococcal substrates in the presence of ArcA, likely due to an inhibition of FimA production. This work suggests that ArcA may have the potential to be a specific antibiofilm agent to fight P. gingivalis infections.