McCormick Susan P, Alexander Nancy J
Mycotoxin Research Unit, US Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, 1815 North University Avenue, Peoria, IL 61604-3902, USA.
Can J Microbiol. 2007 May;53(5):572-9. doi: 10.1139/W07-025.
The biosyntheses of both macrocyclic trichothecenes in Myrothecium roridum and simple trichothecenes in Fusarium species begin with the cyclization of farnesyl pyrophosphate to form the sesquiterpene hydrocarbon trichodiene. A previous study showed that Myrothecium has a cluster of 3 genes that are homologous with Fusarium trichothecene genes: Tri4, a P450 oxygenase; Tri5, the sesquiterpene cyclase; and Tri6, a zinc-finger regulatory gene. Fusarium graminearum Tri4 (FgTri4) and M. roridum MrTri4 (MrTri4) have 66.9% identity. In this study, MrTri4 was expressed in Fusarium verticillioides. Liquid cultures of transformant strains expressing MrTri4 converted exogenous trichodiene to isotrichodiol, indicating that MrTri4 controls 3 oxygenation steps and that the product of MrTRI4 is isotrichodiol.
在拟枝孢镰刀菌中大环单端孢霉烯族毒素的生物合成以及在镰孢菌属中简单单端孢霉烯族毒素的生物合成均始于法尼基焦磷酸的环化，以形成倍半萜烃单端孢霉烯。先前的一项研究表明，拟枝孢镰刀菌有一组与镰孢菌单端孢霉烯族毒素基因同源的3个基因：Tri4，一种细胞色素P450加氧酶；Tri5，倍半萜环化酶；以及Tri6，一种锌指调控基因。禾谷镰孢菌Tri4（FgTri4）与拟枝孢镰刀菌MrTri4（MrTri4）有66.9%的一致性。在本研究中，MrTri4在轮枝镰孢菌中表达。表达MrTri4的转化菌株的液体培养物将外源性单端孢霉烯转化为异三醇，这表明MrTri4控制3个氧化步骤，且MrTRI4的产物是异三醇。
