L-山梨糖提高木霉纤维素酶合成速率机制的研究

THE MECHANISM OF INCREASING CELLULASEBIOSYNTHESIS RATE IN TRICHODERMABY L-SORBOSE

在0.5％葡萄糖-Mandels盐培养液中添加终浓度为0.5％的L-山梨糖,可使里斯木霉(Trichoderma reesei C 30)和拟康氏木霉(Trichoderma pseudokoningii S38)的内切和外切β-1,4葡聚糖酶合成速率在培养的2天内提高4倍。与此同时β-葡萄糖苷酶的合成没有明显变化。L-山梨糖能明显抑制菌丝生长,但对葡萄糖的吸收没有影响,对菌丝分泌纤维素酶的机制影响不大。其对酶合成的促进可能主要是通过降低了菌丝体的生长速率。

In a glucose-Mandels salt medium supplied with 0.5% (W/V) L-sorbose, both Trichoderma reesei C30 and Trichoderma pseudokoningii S38 had a four-fold increase of the glucanase activities in 2 days compared with in medium without L-sorbose, meanwhile the β-glucosidase synthesis did not change obviously. L-sorbose did not affect the uptake rate of glucose, but strongly inhibited the mycelium growth which might be correlated to the increase of cellulase synthesis. The increase of cellulase synthesis by L-sorbose resulted from enzyme de movo synthesis rather than incerase of enzyme secretion.