Although biotin and lipoic acid are two universally conserved cofactors essential for intermediary metabolism, their synthetic pathways have become known only in recent years. Both pathways have unusual features. Biotin synthesis in Escherichia coli requires a methylation that is later removed whereas lipoic acid is assembled on the enzymes where it is required for activity by two different pathways.

中文翻译：

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生物素合成和硫辛酸组装研究进展。

尽管生物素和硫辛酸是中间代谢必不可少的两个普遍保守的辅因子，但它们的合成途径仅在最近几年才为人所知。两种途径都有不同寻常的特征。大肠杆菌中的生物素合成需要甲基化，该甲基化随后会被除去，而硫辛酸则通过两种不同的途径在酶上进行组装，而这是酶活性所必需的。