CreA-mediated repression of gene expression occurs at low monosaccharide levels during fungal plant biomass conversion in a time and substrate dependent manner

The Cell Surface

卷:7

Anna Lipzen¹  Claire Khosravi¹  Miia R. Mäkelä¹  Juying Yan¹  Roland S. Kun¹  Evy Battaglia¹  Sacha Dalhuijsen¹  Ronnie J.M. Lubbers²  Cindy Chen²  Vivian Ng²  Maria Victoria Aguilar Pontes²  Mao Peng²  Igor V. Grigoriev²  Paul Daly²  Jaap Visser³  Ronald P. de Vries⁴  Mei Wang⁴ 

[1] Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands;

[2] Fungal Physiology, Westerdijk Fungal Biodiversity Institute, &

[3] Microbiology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands;

[4] USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States;

关键词: creA;    Carbon catabolite repression;    Transcription factor;    Aspergillus niger;    Fungal plant biomass conversion;   

DOI  :  

来源: DOAJ

【 摘 要 】

Carbon catabolite repression enables fungi to utilize the most favourable carbon source in the environment, and is mediated by a key regulator, CreA, in most fungi. CreA-mediated regulation has mainly been studied at high monosaccharide concentrations, an uncommon situation in most natural biotopes. In nature, many fungi rely on plant biomass as their major carbon source by producing enzymes to degrade plant cell wall polysaccharides into metabolizable sugars. To determine the role of CreA when fungi grow in more natural conditions and in particular with respect to degradation and conversion of plant cell walls, we compared transcriptomes of a creA deletion and reference strain of the ascomycete Aspergillus niger during growth on sugar beet pulp and wheat bran. Transcriptomics, extracellular sugar concentrations and growth profiling of A. niger on a variety of carbon sources, revealed that also under conditions with low concentrations of free monosaccharides, CreA has a major effect on gene expression in a strong time and substrate composition dependent manner. In addition, we compared the CreA regulon from five fungi during their growth on crude plant biomass or cellulose. It showed that CreA commonly regulated genes related to carbon metabolism, sugar transport and plant cell wall degrading enzymes across different species. We therefore conclude that CreA has a crucial role for fungi also in adapting to low sugar concentrations as occurring in their natural biotopes, which is supported by the presence of CreA orthologs in nearly all fungi.

【 授权许可】

Unknown