Research Area of Gene Technology and Applied Biochemistry, Institute for Chemical Engineering, Vienna University of Technology, Gumpendorfer Strasse 1a/1665, A-1060 Vienna, Austria.
Appl Environ Microbiol. 2011 Jul;77(13):4553-63. doi: 10.1128/AEM.00513-11. Epub 2011 May 20.
Trichoderma reesei (Hypocrea jecorina) is nowadays the most important industrial producer of cellulase and hemicellulase enzymes, which are used for pretreatment of cellulosic biomass for biofuel production. In this study, we introduce a novel component, GRD1 (glucose-ribitol dehydrogenase 1), which shows enzymatic activity on cellobiose and positively influences cellulase gene transcription, expression, and extracellular endo-1,4-β-D-glucanase activity. grd1 is differentially transcribed upon growth on cellulose and the induction of cellulase gene expression by sophorose. The transcription of grd1 is coregulated with that of cel7a (cbh1) under inducing conditions. GRD1 is further involved in carbon source utilization on several carbon sources, such as those involved in lactose and D-galactose catabolism, in several cases in a light-dependent manner. We conclude that GRD1 represents a novel enhancer of cellulase gene expression, which by coregulation with the major cellulase may act via optimization of inducing mechanisms.
里氏木霉（Hypocrea jecorina）如今是纤维素酶和半纤维素酶的最重要的工业生产菌，这些酶被用于生物燃料生产中纤维素生物质的预处理。在这项研究中，我们引入了一个新的成分，GRD1（葡萄糖-肌醇脱氢酶 1），它对纤维二糖表现出酶活性，并积极影响纤维素酶基因的转录、表达和细胞外内切-1,4-β-D-葡聚糖酶活性。GRD1 在纤维素上生长和通过棉子糖诱导纤维素酶基因表达时会有差异转录。在诱导条件下，grd1 的转录与 cel7a（cbh1）的转录共同调节。GRD1 还进一步参与了几种碳源的碳源利用，例如参与乳糖和 D-半乳糖分解代谢的碳源，在某些情况下以光依赖性方式参与。我们得出结论，GRD1 是一种新型的纤维素酶基因表达增强子，通过与主要纤维素酶的共同调节，可能通过优化诱导机制发挥作用。
