Zhu Lingyi, Wang Xiaozheng, Shi Qing, Huang Tingting, Yang Ruihuan, Zou Lifang, Chen Gongyou, Deng Zixin, Gu Yucheng, Abe Ikuro, Lin Shuangjun
State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
Haihe Laboratory of Synthetic Biology, Tianjin 300308, China.
JACS Au. 2025 Jun 11;5(7):3008-3013. doi: 10.1021/jacsau.5c00358. eCollection 2025 Jul 28.
Pseudoiodinine (PSD) is a N-N bond-containing natural product with profound antimicrobial and antifungal activities. In this work, we have completed the PSD biosynthetic pathway by explicating the final three steps, which involve an enigmatic N-N bond formation in a ring contraction process. As a starting material, 1,6-didesmethyltoxoflavin (1,6-DDMT) is sequentially methylated by PsdF and PsdA to give 5-methoxy-6-desmethyltoxoflavin (5-OCH-6-DMT), which then undergoes oxidative decarboxylation for the ring-contractive N-N bond formation to generate the pyrazole ring catalyzed by PsdB, a novel vicinal oxygen chelate superfamily (VOC) protein. This is the first enzyme in the VOC family to catalyze such a reaction, providing new insight into N-N bond formation.
伪碘宁（PSD）是一种含有N-N键的天然产物，具有很强的抗菌和抗真菌活性。在这项工作中，我们通过阐明最后三步完成了PSD的生物合成途径，这三步涉及在环收缩过程中神秘的N-N键形成。作为起始原料，1,6-二去甲基毒黄素（1,6-DDMT）先后被PsdF和PsdA甲基化，生成5-甲氧基-6-去甲基毒黄素（5-OCH-6-DMT），然后它进行氧化脱羧反应以形成环收缩的N-N键，生成由新型邻位氧螯合超家族（VOC）蛋白PsdB催化的吡唑环。这是VOC家族中第一种催化此类反应的酶，为N-N键的形成提供了新的见解。
