Acid hydrolysis of bacterial cellulose reveals different modes of synergistic action between cellobiohydrolase I and endoglucanase I.
Intact and partially acid hydrolyzed cellulose from Acetobacter xylinum were used as model substrates for cellulose hydrolysis by 1,4-beta-D-glucan-cellobiohydrolase I (CBH I) and 1,4-beta-D-endoglucanase I (EG I) from Trichoderma reesei. A high synergy between CBH I and EG I in simultaneous action was observed with intact bacterial cellulose (BC), but this synergistic effect was rapidly reduced by acid pretreatment of the cellulose. Moreover, a distinct synergistic effect was observed upon sequential endo-exo action on BC, but not on bacterial microcrystalline cellulose (BMCC). A mechanism for endo-exo synergism on crystalline cellulose is proposed where the simultaneous action of the enzymes counteract the decrease of activity caused by undesirable changes in the cellulose surface microstructure.
Väljamäe
P
P
Institute of Molecular and Cell Biology, University of Tartu, Estonia.
Sild
V
V
Nutt
A
A
Pettersson
G
G
Johansson
G
G
D000091:Acetobacter / Q000201:enzymology; D000143:Acids / Q000494:pharmacology*; D002480:Cellulase / Q000737:chemistry / Q000378:metabolism*; D002482:Cellulose / Q000737:chemistry / Q000378:metabolism*; D043366:Cellulose 1,4-beta-Cellobiosidase; D004305:Dose-Response Relationship, Drug; D006868:Hydrolysis; D007700:Kinetics; D015233:Models, Statistical; D011485:Protein Binding; D013997:Time Factors; D014242:Trichoderma / Q000201:enzymology
D000143:Acids; D002482:Cellulose; D002480:Cellulase; D043366:Cellulose 1,4-beta-Cellobiosidase