The H₂O₂‐promoted desulfuration of 5‐substituted 2‐thiouridines (R5S2U) [present in the first (wobble) position of the anticodon of transfer RNAs, tRNAs], either alone or within an RNA/tRNA chain, is catalyzed by cytochrome c (cyt c). The presence of uridine sulfenic, sulfinic, and sulfonic acid intermediates in the pathway of the cyt c/H₂O₂‐peroxidase‐mediated 2‐thiouridine→4‐pyrimidinone nucleoside transformation is documented.

中文翻译：

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细胞色素c催化转移RNA中2-硫代尿苷的过氧化氢辅助氧化脱硫

H ₂ O ₂促进的5-取代的2-硫尿苷（R5S2U）的脱硫[存在于转移RNA，tRNA的反密码子的第一个（摆动）位置]，可以单独催化，也可以在RNA / tRNA链中催化细胞色素 c（cyt  c）。cyt c / H ₂ O _2-过氧化物酶介导的2-硫代尿苷→4-嘧啶酮核苷转化途径中存在尿苷亚磺酸，亚磺酸和磺酸中间体 。