Biosynthesis of flavin adenine dinucleotides in most prokaryotes is catalyzed by a family of bifunctional flavin adenine dinucleotide (FAD) synthetases. These enzymes carry out the dual functions of phosphorylation of flavin mononucleotide (FMN) and its subsequent adenylylation to generate FAD. Using various sequence analysis methods, a new domain has been identified in the N-terminal region that is well conserved in all the bacterial FAD synthetases. We also identify remote similarity of this domain to the nucleotidyl transferases and, hence, this domain is suggested to be invloved in the adenylylation reaction of FAD synthetases.

中文翻译：

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原核生物双功能FAD合成酶中的保守结构域可以潜在地催化核苷酸转移。

大多数原核生物中黄素腺嘌呤二核苷酸的生物合成是由双功能黄素腺嘌呤二核苷酸（FAD）合成酶催化的。这些酶具有黄素单核苷酸（FMN）磷酸化及其随后的腺苷酸化生成FAD的双重功能。使用各种序列分析方法，已经在所有细菌FAD合成酶中高度保守的N末端区域鉴定了一个新域。我们还确定了该域与核苷酸转移酶的远程相似性，因此，该域建议用于FAD合成酶的腺苷酸化反应中。