β(1,3)-Glucan utilization systems in the order Bacteroidales. (A) Strain-specific, syntenic β(1,3)-glucan utilization loci (1,3GUL) from Bacteroides uniformis, B. thetaiotaomicron, B. fluxus, B. cellulosilyticus, Dysgonomonas mossii, and Prevotella loescheii. Genome locus tags constituting 1,3GUL boundaries are indicated. Predicted or confirmed (this work) functional annotations are denoted below each gene. HTCS, hybrid two-component system sensor/regulator; SusR-like sensor-regulator; TBDT, SusC-like TonB-dependent transporter; SGBP-A, SusD-like cell-surface glycan-binding protein; SGBP-B, sequence-divergent cell-surface glycan-binding protein; GHn, member of glycoside hydrolase family n. (B) Model of B. uniformis laminarin utilization based on the present study and by analogy with the archetypal starch utilization system (Sus) (10, 13). Gene products are colored analogously to panel A, and predicted N-terminal lipidation following signal peptidase II cleavage is indicated with a black squiggle.