ARS | Publication request: Functional characterization of two distinct xyoglucanases from rumenal microbes

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 11, 2010
Publication Date: March 23, 2010
Citation: Wong, D., Chan, V.J., Mccormack, A.A., Batt Throne, S.B. Functional characterization of two distinct xyoglucanases from rumenal microbes. Meeting Abstract, AGFD 125.

Technical Abstract: Xyloglucans are known to function by binding to cellulose microfibrils, crosslinking adjacent fibers forming cellulose-XG networks important for modulation of rigidity and extensibility of the primary cell wall of plants. Enzymatic hydrolysis and modification of xyloglucans has received considerable interest for biotechnological applications particularly in increasing the digestibility of cellulose for more efficient biomass conversion. Recent studies have isolated two xyloglucanases (XEG5A and XEG5B) from rumenal microbes, which possessed an (a/b)8 fold typical of GH family 5. The cleavage patterns on tamarind xyloglucan and oligoxyloglucans suggested one being an endo- and the other exo-enzyme. The XEG5B protein molecule consisted of a loop segment blocking one end of the active site, which potentially provided the enzyme with exo-action. Kinetics and inhibition studies also revealed that each of the two enzymes had uniquely different biochemical characteristics.