ThiC is an [Fe-S] cluster protein that requires AdoMet to generate the 4-amino-5-hydroxymethyl-2-methylpyrimidine moiety in thiamin synthesis
ThiC is an [Fe-S] cluster protein that requires AdoMet to generate the 4-amino-5-hydroxymethyl-2-methylpyrimidine moiety in thiamin synthesis
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DOI：
10.1021/bi8010253
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发表时间：
2008-09-02
期刊：
影响因子：
2.9
通讯作者：
Downs, Diana M.
中科院分区：
文献类型：
--
作者：
Martinez-Gomez, N. Cecilia;Downs, Diana M.
焦磷酸硫胺是所有生物体必需的辅助因子。硫胺素的生物合成需要独立合成4-氨基-5-羟甲基-2-甲基嘧啶焦磷酸（HMP-PP）和5-羟乙基-4-甲基噻唑磷酸（THZ-P）基团。在细菌中，嘧啶部分来源于5-氨基咪唑核糖肽（AIR），而thc是已知的唯一在体内进行这种转化所需的基因产物。我们在这里报道了从肠沙门氏菌中纯化和鉴定的thc蛋白。数据显示，当AIR、s -腺苷蛋氨酸（AdoMet）和适当的还原剂存在时，该蛋白产生HMP。进一步表明，钛具有氧不稳定的[Fe-S]簇，这是该活性所必需的。
Thiamin pyrophosphate is a required cofactor in all organisms. The biosynthesis of thiamin requires the independently synthesized 4-amino-5-hydroxymethyl-2-methylpyrimidine pyrophosphate (HMP-PP) and 5-hydroxyethyl-4-methylthiazole phosphate (THZ-P) moieties. In bacteria, the pyrimidine moiety is derived from 5-aminoimidazole ribotide (AIR), and ThiC is the only gene product known to be required for this conversion in vivo. We report here the purification and characterization of the ThiC protein from Salmonella enterica. The data showed this protein generated HMP when AIR, S-adenosylmethionine (AdoMet), and an appropriate reducing agent were present. It is further shown that ThiC carries an oxygen labile [Fe-S] cluster essential for this activity.