Comparison of BxlG, BxlF, and BxlE sequences with those of other proteins. (A) The consensus sequences conserved in membrane proteins of ABC transporters and the corresponding regions of BxlG and BxlF are shown. The number of the first amino acid in each line is shown on the left. Residues that are identical are indicated by boldface letters. St, S. thermoviolaceus OPC-520; Sc, S. coelicolor A3 (2); Sr, S. reticuli. (B) A sequence in BxlE is compared with the signature sequences of sugar-binding proteins of cluster 1. St, S. thermoviolaceus OPC-520; Sc, S. coelicolor A3 (2); Sr, S. reticuli; So, S. olivaceoviridis; Ec, E. coli; Sm, Streptococcus mutans.