Cellulase production on glucose-based media by the UV-irradiated mutants of Trichoderma reesei.
From 22,791 mutants of a cellulase hyper-producing strain of Trichoderma reesei (Hypocrea jecorina), ATCC66589, as the parent, we selected two mutants, M2-1 and M3-1, that produce cellulases in media containing both cellulose and glucose. The mutation enabled the mutants to produce cellulases, which were measured as p-nitrophenyl beta-D: -lactopyranoside-hydrolyzing activities, in media with glucose as a sole carbon source, although M2-1 exhibited different sensitivities to glucose from M3-1. When the mutants were grown for 8 days on a medium with cellulose as a sole carbon source, the filter-paper-degrading activities (FPAs) per gram of cellulose were 257 and 281 U for M2-1 and M3-1, respectively, values that were 1.1-1.2 times higher than that of the parental strain. Cellulase production by M2-1 and M3-1 on a medium with a continuously fed mixture of glucose and cellobiose resulted in 214 and 210 U of FPA/gram carbon sources, respectively, whereas less efficient production (140 U of FPA/gram carbon source) was achieved by the parental strain. The improved cellulase productivity of the mutants allows us to use glucose as a carbon source for efficient on-site production of cellulases with quality/quantity-controlled feeding of soluble carbon sources and inducers.
Ike
Masakazu
M
National Food Research Institute, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan.
Park
Jeung-yil
JY
Tabuse
Mine
M
Tokuyasu
Ken
K
D002480:Cellulase / Q000235:genetics / Q000378:metabolism*; D003470:Culture Media / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D009154:Mutation / Q000528:radiation effects*; D014242:Trichoderma / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects; D014466:Ultraviolet Rays
D003470:Culture Media; D005656:Fungal Proteins; D002480:Cellulase; D005947:Glucose