Fum3p, a 2-ketoglutarate-dependent dioxygenase required for C-5 hydroxylation of fumonisins in Fusarium verticillioides
Fum3p, a 2-ketoglutarate-dependent dioxygenase required for C-5 hydroxylation of fumonisins in Fusarium verticillioides
复制标题
DOI：
10.1128/aem.70.4.1931-1934.2004
复制
发表时间：
2004-04-01
影响因子：
4.4
通讯作者：
Du, LC
中科院分区：
文献类型：
--
作者：
Ding, Y;Bojja, RS;Du, LC
伏马菌素是由几种农业上重要的镰刀菌属物种产生的聚酮衍生的真菌毒素。B系列伏马菌素FB 1、FB 2、FB 3和FB 4是由野生型轮枝镰刀菌菌株产生的伏马菌素，不同之处在于连接到碳主链的羟基的数量和位置。我们的特点是由FUM 3，伏马菌素生物合成基因簇中的基因编码的蛋白质。从酿酒酵母中异源表达并纯化了33-kDa FUM 3蛋白（Fum 3 p）。表达Fum 3 p的酵母细胞将FB 3转化为FB 1，表明Fum 3 p催化伏马菌素的C-5羟基化。通过测定从酵母细胞纯化的Fum 3 p的活性来验证该结果。纯化的Fum 3 p的C-5羟化酶活性需要2-酮戊二酸、Fe 2+、抗坏血酸和过氧化氢酶，所有这些都是2-酮戊二酸依赖性双加氧酶所需的。该蛋白质还包含两个在该双加氧酶家族中高度保守的His基序。因此，Fum 3 p是添加伏马菌素的C-5羟基所需的2-酮戊二酸依赖性双加氧酶。
Fumonisins are polyketide-derived mycotoxins produced by several agriculturally important Fusarium species. The B series fumonisins, FB1, FB2, FB3, and FB4, are fumonisins produced by wild-type Fusarium verticillioides strains, differing in the number and location of hydroxyl groups attached to the carbon backbone. We characterized the protein encoded by FUM3, a gene in the fumonisin biosynthetic gene cluster. The 33-kDa FUM3 protein (Fum3p) was heterollogously expressed and purified from Saccharomyces cerevisiae. Yeast cells expressing the Fum3p converted FB3 to FB1, indicating that Fum3p catalyzes the C-5 hydroxylation of fumonisins. This result was verified by assaying the activity of Fum3p purified from yeast cells. The C-5 hydroxylase activity of purified Fum3p required 2-ketoglutarate, Fe2+, ascorbic acid, and catalase, all of which are required for 2-ketoglutarate-dependent dioxygenases. The protein also contains two His motifs that are highly conserved in this family of dioxygenases. Thus, Fum3p is a 2-ketoglutarate-dependent dioxygenase required for the addition of the C-5 hydroxyl group of fumonisins.