Induction of cellulose- and xylan-degrading enzyme complex in the yeast Trichosporon cutaneum |
| |
Authors: | Mária Hrmová Peter Biely Mária Vr?anská Eva Petráková |
| |
Affiliation: | (1) Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta, CS-842 38 Bratislava, Czechoslovakia |
| |
Abstract: | The specificity of induction of cellulose- and xylan-degrading enzymes was investigated on the yeast strain Trichosporon cutaneum CCY 30-5-4 using series of compounds structurally related to cellulose and xylan, including monosaccharides, glycosides, glucooligosaccharides and xylooligosaccharides. Determination of activities of secreted cellulase and -xylanase, intracellular, cell wall bound and extracellular -glucosidase and -xylosidase revealed that: (1) The synthesis of xylan-degrading enzymes is induced in the cell only by xylosaccharides, 1,3--xylobiose, 1,2--xylobiose, 1,4--xylosyl-L-arabinose, 1,4--xylobiose and thioxylobiose being the best inducers. The xylan-degrading enzymes show different pattern of development in time and discrete cellular localization, i.e. intracellular -xylosidase precedes extracellular -xylanase. (2) A true cellulase is not inducible by glucosaccharides and cellulose. Negligible constitutive cellulase activity was detected which was about two orders lower than an induced cellulase in the typical cellulolytic fungus Trichoderma reesei QM 9414. (3) The best inducer of intracellular -glucosidase splitting cellobiose was thiocellobiose in a wide range of concentration (0.1–10 mM), whereas xylosaccharides at high concentrations induced -xylosidase of xylobiose type and a non-specific aryl -D-glucosidase.The results were confirmed by growing cells on cellulose and xylan. T. cutaneum was found to be a xylan-voracious yeast, unable to grow on cellulose. |
| |
Keywords: | Cellulase -Glucosidase" target="_blank">gif" alt="beta" align="MIDDLE" BORDER="0">-Glucosidase -Xylanase" target="_blank">gif" alt="beta" align="MIDDLE" BORDER="0">-Xylanase -Xylosidase" target="_blank">gif" alt="beta" align="MIDDLE" BORDER="0">-Xylosidase Trichosporon cutaneum |
本文献已被 SpringerLink 等数据库收录! |
|