The fibronectin type 3-like repeat from the Clostridium thermocellum cellobiohydrolase CbhA promotes hydrolysis of cellulose by modifying its surface.

ABSTRACT: Fibronectin type 3 homology domains (Fn3) as found in the cellobiohydrolase CbhA of Clostridium thermocellum are common among bacterial extracellular glycohydrolases. The function of these domains is not clear. CbhA is modular and composed of an N-terminal family IV carbohydrate-binding domain (CBDIV), an immunoglobulin-like domain, a family 9 glycosyl hydrolase catalytic domain (Gh9), two Fn3-like domains (Fn3(1,2)), a family III carbohydrate-binding domain (CBDIII), and a dockerin domain. Efficiency of cellulose hydrolysis by truncated forms of CbhA increased in the following order: Gh9 (lowest efficiency), Gh9-Fn3(1,2) (more efficient), and Gh9-Fn3(1,2)-CBDIII (greatest efficiency). Thermostability of the above constructs decreased in the following order: Gh9 (most stable), Gh9-Fn3(1,2)

SUBMITTER: Kataeva IA 

PROVIDER: S-EPMC124122 | biostudies-literature | 2002 Sep

REPOSITORIES: biostudies-literature