State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, P.R. China.
J Basic Microbiol. 2021 Feb;61(2):122-132. doi: 10.1002/jobm.202000566. Epub 2021 Jan 4.
The filamentous fungus Trichoderma reesei is an important producer of industrial enzymes, and possesses abundant extracellular protease genes based on the genome sequence data. However, the production of extracellular proteases remains poorly understood. Here, protease production was extensively investigated on different carbon (glucose and lactose) and nitrogen sources ((NH ) SO , NaNO , peptone, and corn steep liquor). It was found that protease production was dominantly regulated by nitrogen sources. Organic nitrogen sources were beneficial for protease production, while the preferred nitrogen source (NH ) SO inhibited the expression of proteases. As for carbon sources, lactose was a more effective inducer than glucose for protease production. The protease activity was further examined by protease inhibitors, which suggested that protease activity was predominantly inhibited by phenylmethanesulfonyl fluoride (PMSF) and slightly suppressed by ethylenediaminetetraacetic acid (EDTA). Moreover, proteomic analysis revealed a total of 29 extracellular proteases, including 13 serine proteases, 6 aspartic proteases, and 10 metalloproteases. In addition, seven proteases were found to be present among all conditions. These results showed the regulatory profile of extracellular protease production in Trichoderma reesei grown on various carbon and nitrogen sources, which will facilitate the development of T. reesei to be an effective workhorse for enzyme or high-value protein production in industry.
里氏木霉是一种重要的工业酶生产真菌，根据基因组序列数据，其拥有丰富的细胞外蛋白酶基因。然而，细胞外蛋白酶的生产仍知之甚少。在此，我们广泛研究了不同碳（葡萄糖和乳糖）和氮源（（NH ）SO 、NaNO 、蛋白胨和玉米浆）对蛋白酶生产的影响。结果发现，氮源是蛋白酶生产的主要调控因素。有机氮源有利于蛋白酶的生产，而首选氮源（NH ）SO 抑制蛋白酶的表达。至于碳源，乳糖比葡萄糖更能有效诱导蛋白酶的生产。蛋白酶活性通过蛋白酶抑制剂进一步检测，结果表明蛋白酶活性主要受苯甲基磺酰氟（PMSF）抑制，稍受乙二胺四乙酸（EDTA）抑制。此外，蛋白质组学分析共发现 29 种细胞外蛋白酶，包括 13 种丝氨酸蛋白酶、6 种天冬氨酸蛋白酶和 10 种金属蛋白酶。此外，在所有条件下都发现有 7 种蛋白酶存在。这些结果显示了里氏木霉在不同碳源和氮源上生长时细胞外蛋白酶生产的调控模式，这将有助于里氏木霉成为工业中酶或高价值蛋白质生产的有效工具菌。
