Activity profile for S. mutans UA159, JH1005, LT11, NG8, UA140, BM71, and GS5 with p-nitrophenylbutyrate (p-NPB), o-nitrophenylbutyrate (o-NPB), p-nitrophenylacetate (p-NPA), and butyrylthiocholine iodide (BTC). Data are plotted with standard error of the the mean (N = 3). *represents statistically significant differences (p < .05).