Evidence that a low-affinity sucrose phosphotransferase activity in Streptococcus mutans GS-5 is a high-affinity trehalose uptake system.

High-affinity sucrose uptake in the oral pathogen Streptococcus mutans is mediated by the phosphoenolpyruvate-dependent phosphotransferase system. In this report, we provide evidence that a lower-affinity sucrose phosphotransferase system in S. mutans GS-5, previously described by others, is in fact a high-affinity trehalose uptake system that also recognizes sucrose as a substrate.