Group A Streptococcal rofA Gene Is Involved in the Control of Several Virulence Genes and Eukaryotic Cell Attachment and Internalization

The serotype M6 group A streptococcal RofA regulator was previously shown to exert a direct positive control of protein F1 expression and, concomitantly, fibronectin binding. Using a serotype M6 rofA mutant, we demonstrate here that this regulator has a potentially indirect negative influence on the expression of the mga, emm6, pel-sagA, and speA virulence genes. Additionally, the rofA mutant exhibited reduced eukaryotic cell internalization rates in combination with decreased host cell viability.