文献类型：期刊文献

英文题名：Enhanced cellulase production by decreasing intercellular pH through H+-ATPase gene deletion in Trichoderma reesei RUT-C30

作者：Liu, Pei[1]; Zhang, Guoxiu[1]; Chen, Yumeng[1]; Zhao, Jian[1]; Wang, Wei[1]; Wei, Dongzhi[1]

机构：[1] State Key Lab of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China

年份：2019

卷号：12

期号：1

外文期刊名：Biotechnology for Biofuels

收录：EI(收录号：20193507374194)

语种：英文

外文关键词：Ammonia - Lignocellulose - Calcium - Carbon - Genes - Industrial chemicals

摘要：Background: Cellulolytic enzymes produced by Trichoderma reesei are widely used for the industrial production of biofuels and chemicals from lignocellulose. We speculated that intracellular pH during the fermentation process can affect cellulase induction. Results: In this study, two H+-ATPase genes, tre76238 and tre78757, were first identified in T. reesei. Deletion of tre76238 and tre78757 in T. reesei RUT-C30 confirmed that tre76238 has a major function in maintaining intracellular pH, whereas tre78757 has a minor function. The tre76238 deletion strain Δ76238 displayed a high level of cellulase production using cellulase-repressive glucose as a sole carbon source, along with intracellular acid accumulation and growth retardation. Our results indicated that intracellular acid accumulation in Δ76238 stimulated a significant increase in the cytosolic Ca2+ levels. Ca2+ channels were shown to be necessary for cellulase production using glucose as the carbon source in Δ76238. Delayed Δ76238 growth could be reversed by optimizing the medium's nitrogen sources to produce ammonia for intracellular acid neutralization in the early phase. This may be useful for scale-up of cellulase production using glucose as the carbon source. Conclusions: This study provides a new perspective for significant alterations in the cellulase expression pattern of T. reesei Δ76238, indicating a new mechanism for cellulase regulation under conditions of low intracellular pH. ? 2019 The Author(s).