Characterization of the biosynthesis system for thiouridine in tRNA

分析了嗜热菌tRNA中硫尿苷的生物合成途径。构建了一种用于tRNA巯基化反应的体外重组体系。通过使用在体内系统，巯基化酶TtuA的反应机制的建议。研究表明，生物合成蛋白TtuB也是一种蛋白质修饰剂，调节tRNA的巯基化反应。这表明真核泛素系统的古老起源。

The biosynthesis pathway of thiouridine found in tRNA of thermophilic bacteria was analyzed. An in vitro reconstitution system for tRNA thiolation reaction was constructed. By using an in vivo system, a reaction mechanism for the thiolation enzyme TtuA was suggested. It was suggested that one of the biosynthesis protein, TtuB, also function as a protein modifier, which regulates the thiolation reaction of tRNA. This suggests an ancient origin of the eukaryotic ubiquitin system.