Primarystudies on several cellulase components with special characteristics purified fromTrichoderma pseudokoningii S38

Ten cellulase components, consisting of five different endoglucanases (EG1-EG5), three cellobiohydrolases (CBHI, CBHX-I and CBHX-2) and two β-glucosidases (βGI and βG2) from Trichoderma pseudokoningii S38, were successively purified by Sephadex G-50, DEAE-Sephadex A25 and finally by DEAE-HPLC-8HR column chromatography. The purified enzyme components were characterized with repect to their molecular mass, pl and, especially, substrate specificities. EG I and EG2 were the main endoglucanases and were similar to other EGs obtained previously. However, EG5 showed the highest activity for forming short fibres from absorbent cotton, although its ability to hydrolyse carboxymethylcellulose to produce reducing sugars was very poor. Two new CBHs, termed CBHX-I and CBHX-2, had characteristics different from those of CBHI and CBHII. CBHX-I showed a lower ability to hydrolyse absorbent cotton to produce cellobiose than other CBHs, but it had strong synergistic action with CBHI for the hydrolysis of crystalline cellulose. Compared with βGI, βG2 had a higher transglycosidase activity and a lower ability to hydrolyse cellobiose to glucose. The specificities of these ten components for a range of substrates were determined.