Panchanawaporn Sarocha, Chutrakul Chanikul, Jeennor Sukanya, Anantayanon Jutamas, Laoteng Kobkul
Functional Ingredients and Food Innovation Research Group (IFIG), National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand.
J Fungi (Basel). 2024 Dec 25;11(1):6. doi: 10.3390/jof11010006.
Enzyme-mediated protein degradation is a major concern in industrial fungal strain improvement, making low-proteolytic strains preferable for enhanced protein production. Here, we improved food-grade BCC7051 by manipulating the transcriptional regulation of protease-encoding genes. Genome mining of the transcription factor and computational analysis confirmed its deduced amino acid sequence sharing evolutionary conservation across and spp. The AoPrtR protein, which is classified into the Zn(II)2-Cys6-type transcription factor family, manipulates both intra- and extracellular proteolytic enzymes. Our transcriptional analysis indicated that the regulation of several protease-encoding genes was AoPrtR-dependent, with AoPrtR acting as a potent activator for extracellular acid-protease-encoding genes and a likely repressor for intracellular non-acid-protease-encoding genes. An indirect regulatory mechanism independent of PrtR may enhance proteolysis. Moreover, AoPrtR disruption increased extracellular esterase production by 2.55-fold, emphasizing its role in protein secretion. Our findings highlight the complexity of AoPrtR-mediated regulation by . Manipulation of regulatory processes through AoPrtR prevents secreted protein degradation and enhances the quantity of extracellular proteins, suggesting the low-proteolytic variant as a promising platform for the production of these proteins. This modified strain has biotechnological potential for further refinement and sustainable production of bio-based products in the food, feed, and nutraceutical industries.
酶介导的蛋白质降解是工业真菌菌株改良中的一个主要问题，因此低蛋白水解活性的菌株更有利于提高蛋白质产量。在此，我们通过调控蛋白酶编码基因的转录调控来改良食品级BCC7051。对转录因子进行基因组挖掘和计算分析证实，其推导的氨基酸序列在[具体物种1]和[具体物种2]中具有进化保守性。AoPrtR蛋白属于Zn(II)2-Cys6型转录因子家族，可调控细胞内和细胞外的蛋白水解酶。我们的转录分析表明，几个蛋白酶编码基因的调控依赖于AoPrtR，AoPrtR作为细胞外酸性蛋白酶编码基因的强效激活剂，而可能是细胞内非酸性蛋白酶编码基因的阻遏物。一种独立于PrtR的间接调控机制可能会增强蛋白水解作用。此外，AoPrtR缺失使细胞外酯酶产量提高了2.55倍，突出了其在蛋白质分泌中的作用。我们的研究结果凸显了AoPrtR介导的[具体调控对象]调控的复杂性。通过AoPrtR对调控过程进行操作可防止分泌蛋白降解并增加细胞外蛋白质的数量，这表明低蛋白水解变体是生产这些蛋白质的有前景的平台。这种改良菌株在食品、饲料和营养保健品行业中进一步优化和可持续生产生物基产品方面具有生物技术潜力。
