Purification, Characterization, and Gene Analysis of Cellulase (Cel8A) fromLysobactersp. IB-9374

Abstract

An enzyme that has both beta-1,4-glucanase and chitosanase activities was found in the culture medium of the soil bacterium Lysobacter sp. IB-9374, a high lysyl endopeptidase-producing strain. The enzyme was purified to homogeneity from the culture filtrate using five purification steps and designated Cel8A. The purified Cel8A had a molecular mass of 41 kDa, as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A pH optimum of 5.0 was found for the beta-1,4-glucanase activity, and pH optima of 5.0 and 7.0 were found for the chitosanase activity. Nucleotide sequencing of the Cel8A gene yielded a deduced amino acid sequence that comprises a 33-amino acid, N-terminal signal peptide and a mature enzyme consisting of a 381-residue polypeptide with a predicted molecular mass of 41,241 Da. The amino acid sequence of the Cel8A, which contains the catalytic module of glycosyl hydrolase family 8, is homologous to beta-1,3-1,4-D-glucanase from Bacillus circulans WL-12 and endoglucanase N-257 from B. circulans KSM-N257.

Cloning of an endoglycanase gene from Paenibacillus cookii and characterization of the recombinant enzyme

“…The recombinant enzyme hydrolyzed not only cellulosic substrates but also chitosan. Several bacterial enzymes possess chitosanase and glucanase activities (Choi et al 2004;Hedges and Wolfe 1974;Kimoto et al 2002;Mitsutomi et al 1998;Ogura et al 2006). The relative activities of the enzyme toward CMC and chitosan were similar to those of GHF-8 chitosanases from Bacillus sp.…”

Isolation and screening of cellulolytic bacteria from soil and optimization of cellulase production and activity

“…According to previous studies, cellulases are active at the pH range of 6.0 to 7.0 from A. Niger [34], 5.0 to 7.0 from Lysobacter sp. [35] and 5.0 to 6.5 from Bacillus strains [36]. Present findings were significant from M. circinelloides (pH 4-7) [379 and B. circulans (4.5-7.0) [38].…”

Ammonia Accumulation of Novel Nitrogen-Fixing Bacteria

“…Nitrogen is an essential element for many biological processes, including those occurring in plants (Ogura et al, 2006). Despite the abundance of atmospheric nitrogen, production of nitrogen fertilisers by the Harber-Bosch process is increasing annually due to the deficiency of ammonia produced by biological nitrogen fixation-the enzyme-catalyzed reduction of nitrogen gas (N 2 ).…”