Induction and Regulation of Cellulase Formation in...
The formation of cellulase in washed mycelia of T.pseudokoningii EA3-867 was markedly induced by sophorose.The cellulase activity，after shaking the mycelial suspension with sophorose，approached maximum within 24 hour culture with a lag period of about 3 hours.The washed mycelia of various species of Trichoderma and that of T.pseudokoningii EA3-867 with various ages were all able to produce cellulase in which C1，Cx-cellulase was Predominantly extracellular，whereas cellobiase wes intracellular.The formation of cellulase was affected by the inducer，minerai elements（nitrogen，phosphorus，iron and manganese）temperature，pH，aeration，and the physiological conditions of the mycelial cells.The optimal concentration of sophorose was 103—105 mol/L，optimal temperature was 30℃.the range of pH used for induction was 3—6，and optimal pH was 5.The production of cellulase was stimulated by O2，but strongly repressed by inhibitors of respiration，such as iodoacetate fluoride，malonate，azide and 2，4-dinitrophenol.The indution of cellulase in washed mycelia was inhibited also by actidione，5-fluouracil and 6-azauracil greatly，but inhibited by actinomycin D only slightly.Furthermore，various sugars，sugar phosphates，glycerol，organic acids，NAD，NADP and ATP all repressed the inductive cellulase formation.The catabolite repression of glucose could not be overcome by c-AMP added to the medium.From these results it is obvious that the induction of cellulase formation is closely related to the respiration and nucleic acid metabolism of fungus.The mode of cellulase synthesis in this microorganism was discussed.(https://www.daowen.com)
[1]Y.S.Zhu and C.Tan，Shanghai Institute of Plant Physiology，Academia Sinica
