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 ((NH4 )2 SO4 , NaNO3 , 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 (NH4 )2 SO4 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.

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里氏木霉中氮源和碳源调控胞外蛋白酶的产生

丝状真菌里氏木霉是工业酶的重要生产者，根据基因组序列数据，其具有丰富的胞外蛋白酶基因。然而，细胞外蛋白酶的产生仍然知之甚少。在这里，广泛研究了不同碳源（葡萄糖和乳糖）和氮源（(NH4 )2 SO4、NaNO3、蛋白胨和玉米浆）的蛋白酶生产。发现蛋白酶生产主要受氮源调节。有机氮源有利于蛋白酶的生产，而优选的氮源 (NH4 )2 SO4 抑制蛋白酶的表达。至于碳源，乳糖是比葡萄糖更有效的蛋白酶产生诱导剂。通过蛋白酶抑制剂进一步检查蛋白酶活性，这表明蛋白酶活性主要被苯甲磺酰氟 (PMSF) 抑制，而被乙二胺四乙酸 (EDTA) 略微抑制。此外，蛋白质组学分析显示共有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，发现所有条件中都存在七种蛋白酶。这些结果显示了生长在各种碳源和氮源上的里氏木霉胞外蛋白酶生产的调控特征，这将促进里氏木霉发展成为工业上酶或高价值蛋白质生产的有效主力。蛋白质组学分析显示共有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，发现所有条件中都存在七种蛋白酶。这些结果显示了生长在各种碳源和氮源上的里氏木霉胞外蛋白酶生产的调控特征，这将促进里氏木霉发展成为工业上酶或高价值蛋白质生产的有效主力。蛋白质组学分析显示共有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，发现所有条件中都存在七种蛋白酶。这些结果显示了生长在各种碳源和氮源上的里氏木霉胞外蛋白酶生产的调控特征，这将促进里氏木霉发展成为工业上酶或高价值蛋白质生产的有效主力。