Crucial roles of single residues in binding affinity, specificity, and promiscuity in the cellulosomal cohesin-dockerin interface.

ABSTRACT: Interactions between cohesin and dockerin modules play a crucial role in the assembly of multienzyme cellulosome complexes. Although intraspecies cohesin and dockerin modules bind in general with high affinity but indiscriminately, cross-species binding is rare. Here, we combined ELISA-based experiments with Rosetta-based computational design to evaluate the contribution of distinct residues at the Clostridium thermocellum cohesin-dockerin interface to binding affinity, specificity, and promiscuity. We found that single mutations can show distinct and significant effects on binding affinity and specificity. In particular, mutations at cohesin position Asn(37) show dramatic variability in their effect on dockerin binding affinity and specificity: the N37A mutant binds promiscuously both to

SUBMITTER: Slutzki M 

PROVIDER: S-EPMC4447945 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature