Identification of a point mutation resulting in loss of cell wall anchoring activity of SrtA of Streptococcus mutans NG5.

Streptococcus mutans NG5 failed to anchor antigen P1 to the cell surface, and such a failure could be attributed to a defective SrtA, which was made defective by a point mutation within the srtA gene. Without a functional SrtA, S. mutans NG5 was not able to perform a number of cell surface-related activities, including saliva-mediated adherence and aggregation.