FIG. 4.

Assignment of the B. cellulosolvens cohesins as type II cohesins. (A) Phylogenetic analysis of CipBc cohesin sequences. The type I cohesins include those from the other known scaffoldins and two other cellulase-binding surface proteins (OlpA from C. thermocellum and OrfX from C. cellulolyticum). In addition to the CipBc cohesins, type II cohesins include the anchoring proteins from C. thermocellum and a putative anchoring protein from A. cellulolyticus. See Materials and Methods for sources of the sequences and abbreviations used in this and subsequent figures. The scale bar in this and subsequent figures indicates percentage (0.1) of amino acid substitutions. (B) Alignment of CipBc cohesin sequences versus types I and II cohesins (Coh-I and Coh-II, respectively). The positions of the β strands, known from the crystal structure of type I cohesins from C. thermocellum, are also shown. The sequence for cohesin 5 (Bc_coh-5) is shown as representative of the 11 B. cellulosolvens cohesins. The conserved sequence identities, similarities, and gaps of the B. cellulosolvens cohesins coincide with those of the type II cohesins.