Proctor Robert H, Busman Mark, Seo Jeong-Ah, Lee Yin Won, Plattner Ronald D
National Center for Agricultural Utilization Research, U.S. Department of Agriculture, Agricultural Research Service, Peoria, IL 61604-3999, USA.
Fungal Genet Biol. 2008 Jun;45(6):1016-26. doi: 10.1016/j.fgb.2008.02.004. Epub 2008 Feb 23.
Most species of Fusarium that produce fumonisin mycotoxins produce predominantly B fumonisins (FBs). However, Fusarium oxysporum strain O-1890 produces predominantly C fumonisins (FCs). In this study, the nucleotide sequence of the fumonisin biosynthetic gene (FUM) cluster in strain O-1890 was determined. The order and orientation of FUM genes were the same as in the previously described clusters in Fusarium verticillioides and Fusarium proliferatum. Coding regions of F. oxysporum and F. verticillioides FUM genes were 88-92% identical, but regions flanking the clusters did not share significant identity. The FUM cluster gene FUM8 encodes an alpha-oxoamine synthase, and fum8 mutants of F. verticillioides do not produce fumonisins. Complementation of a fum8 mutant with the F. verticillioidesFUM8 restored FB production. Complementation with F. oxysporumFUM8 also restored production, but the fumonisins produced were predominantly FCs. These data indicate that different orthologues of FUM8 determine whether Fusarium produces predominantly FBs or FCs.
大多数产生伏马菌素霉菌毒素的镰刀菌物种主要产生B型伏马菌素（FBs）。然而，尖孢镰刀菌菌株O - 1890主要产生C型伏马菌素（FCs）。在本研究中，测定了菌株O - 1890中伏马菌素生物合成基因（FUM）簇的核苷酸序列。FUM基因的顺序和方向与先前描述的轮枝镰孢菌和层出镰刀菌中的簇相同。尖孢镰刀菌和轮枝镰孢菌FUM基因的编码区有88 - 92%的同一性，但簇两侧的区域没有显著的同一性。FUM簇基因FUM8编码一种α - 氧代胺合酶，轮枝镰孢菌的fum8突变体不产生伏马菌素。用轮枝镰孢菌FUM8对fum8突变体进行互补恢复了FB的产生。用尖孢镰刀菌FUM8进行互补也恢复了产量，但产生的伏马菌素主要是FCs。这些数据表明，FUM8的不同直系同源物决定了镰刀菌主要产生FBs还是FCs。
