In an earlier work on lovastatin production by Aspergillus terreus, we found that reactive oxygen species (ROS) concentration increased to high levels precisely at the start of the production phase (idiophase) and that these levels were sustained during all idiophase. Moreover, it was shown that ROS regulate lovastatin biosynthesis. ROS regulation has also been reported for aflatoxins. It has been suggested that, due to their antioxidant activity, aflatoxins are regulated and synthesized like a second line of defense against oxidative stress. To study the possible ROS regulation of other industrially important secondary metabolites, we analyzed the relationship between ROS and penicillin biosynthesis by Penicillium chrysogenum and cephalosporin biosynthesis by Acremonium chrysogenum. Results revealed a similar ROS accumulation in idiophase in penicillin and cephalosporin fermentations. Moreover, when intracellular ROS concentrations were decreased by the addition of antioxidants to the cultures, penicillin and cephalosporin production were drastically reduced. When intracellular ROS were increased by the addition of exogenous ROS (H2O2) to the cultures, proportional increments in penicillin and cephalosporin biosyntheses were obtained. It was also shown that lovastatin, penicillin, and cephalosporin are not antioxidants. Taken together, our results provide evidence that ROS regulation is a general mechanism controlling secondary metabolism in fungi.

中文翻译：

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青霉素和头孢菌素的生物合成也受活性氧的调节。

在关于曲霉曲霉生产洛伐他汀的早期工作中，我们发现活性氧（ROS）浓度正好在生产阶段开始时（高碘化阶段）就增加到了很高的水平，并且这些水平在所有成年期均保持不变。此外，已表明ROS调节洛伐他汀的生物合成。还报道了黄曲霉毒素的ROS调节。已经提出，由于其抗氧化活性，黄曲霉毒素像抗氧化应激的第二道防线一样被调节和合成。为了研究其他工业上重要的次生代谢产物可能的ROS调节，我们分析了ROS与产黄青霉菌合成青霉素和产黄顶孢菌素合成头孢菌素之间的关系。结果显示在青霉素和头孢菌素发酵的中后期有类似的ROS积累。此外，当通过向培养物中添加抗氧化剂来降低细胞内ROS浓度时，青霉素和头孢菌素的产生急剧减少。当通过向培养物中添加外源性ROS（H2O2）来增加细胞内ROS时，青霉素和头孢菌素的生物合成成比例增加。还显示洛伐他汀，青霉素和头孢菌素不是抗氧化剂。两者合计，我们的结果提供证据证明，ROS调节是控制真菌次级代谢的一般机制。青霉素和头孢菌素的生产大大减少。当通过向培养物中添加外源性ROS（H2O2）来增加细胞内ROS时，青霉素和头孢菌素的生物合成成比例增加。还显示洛伐他汀，青霉素和头孢菌素不是抗氧化剂。两者合计，我们的结果提供证据证明，ROS调节是控制真菌次级代谢的一般机制。青霉素和头孢菌素的生产大大减少。当通过向培养物中添加外源性ROS（H2O2）来增加细胞内ROS时，青霉素和头孢菌素的生物合成成比例增加。还显示洛伐他汀，青霉素和头孢菌素不是抗氧化剂。两者合计，我们的结果提供证据证明，ROS调节是控制真菌次级代谢的一般机制。