Purification and Characterization of Endoglucanase and Exoglucanase Components from Trichoderma viride

概要

論文の詳細を見る
Major cellulase components-four endoglucanases (Endo I, II, III and IV) and one exoglucanase (ExoII)-were isolated from a commercial cellulase preparation derived from Trichoderma viride by a series of chromatographic procedures. The average molecular weights were determined by SDS-polyacrylamide gel electrophoresis. Endos I, III and IV, with M_<rs> of 52,000,42,000 and 38,000,respectively, exhibited a more random hydrolytic mode on carboxymethylcellulose (CMC) than Endo II, which has an M_r of 60,000. Endo II showed low activity towards CMC, but out of the four purified endoglucanases this enzyme had tha highest specific activity against Avicel. In the hydrolysis or H_3PO_4-swollen cellulose by Endos I, III and IV, cellobiose was the major product, but equimolar amounts of glucose and cellobiose were formed by Endo II. Exo II, with an M_r of 62,000,released cellobiose as the main product in the hydrolysis of H_3PO_4-swollen cellulose, but glucose was negligible. The combination of Endo I, II, III or IV with Exo II resulted in a synergistic effect in the degradation of Avicel at various combination ratios of these enzymer; the specific optimum ratio of endoglucanase of exoglucanase was largely dependent upon the random hydrolytic mode of the endoglucanase. On the other hand, adsorption of cellulase components was found apparently to obey the Langmuir isotherm, and the thermodynamic parameter (ΔH) was calculated from the adsorption equilibrium constant (K). The enthalpies of adsorption of the endoglucanases were in the range of -2.6--7.2KJmol^<-1>, much smaller than that of Exo II (-19.4KJmol^<-1>). This suggests that Exo Ii shows stronger preferential adsorption than endoglucanases, and that the enthalpy of adsorption will be effective in distinguishing endoglucanase from exoglucanase.
社団法人日本生物工学会の論文
1994-04-25

Purification and Characterization of Endoglucanase and Exoglucanase Components from Trichoderma viride

スポンサーリンク

概要

著者

関連論文

スポンサーリンク