Identification and Functional Characterization of an Endoglucanase KRICT PC-001 from Paenibacillus terrae HPL-003

Abstract

The gene encoding 1,4-β-endoglucanase KRICT PC-001 (1.722 bp; 573 aa) was revealed by a full-length sequence analysis of the bacterium Paenibacillus terrae HPL-003 (KCTC 11987BP) isolated from the soil on Gara Mountain in Korea (CP003107). The molecular weight of the enzyme was estimated as 62 kDa by SDS-PAGE analysis. Endoglucanase KRICT PC-001 contains a catalytic domain of the glycosyl hydrolase family 5 (GH5) and a carbohydrate-binding module X2 (CBM X2). The soluble fraction of the recombinant protein was overexpressed with the pGEX-fusion vector in Escherichia coli BL21 (DE3) and purified using glutathione S-transferase column. The recombinant protein was digested with Factor Xa and eluted from a benzamidine column. Carboxymethyl cellulose was used as a substrate for the enzyme activity analysis. Endoglucanase KRICT PC-001 exhibited a maximum specific activity of 589 U/mg of protein at a temperature of 50°C and pH 5.0.