Unveiling Biosynthesis of the Phytohormone Abscisic Acid in Fungi: Unprecedented Mechanism of Core Scaffold Formation Catalyzed by an Unusual Sesquiterpene Synthase
作者:Junya Takino、Takuto Kozaki、Yoshiro Sato、Chengwei Liu、Taro Ozaki、Atsushi Minami、Hideaki Oikawa
DOI:10.1021/jacs.8b08925
日期:2018.10.3
novel type of sesquiterpene synthase BcABA3 and its unprecedented three-step reaction mechanism involving two neutral intermediates, β-farnesene and allofarnesene. Database searches showed that BcABA3 has no homology with typical sesquiterpene synthases and that the homologous enzyme genes are found in more than 100 bacteria, suggesting that these enzymes form a new family of sesquiterpene synthases.
脱落酸(ABA)是一种众所周知的调节非生物胁迫的植物激素。真菌产生的 ABA 也被认为是真菌病原体的毒力因子。尽管其在真菌中的生物合成途径是由一系列饲养实验提出的,但催化法呢基二磷酸到 α-亚亚乙基乙烷反应的酶仍有待确定。在这项工作中,我们确定了新型倍半萜烯合酶 BcABA3 及其前所未有的三步反应机制,涉及两种中性中间体,β-法呢烯和异法呢烯。数据库搜索表明,BcABA3与典型的倍半萜合酶没有同源性,在100多种细菌中发现了同源酶基因,表明这些酶形成了一个新的倍半萜合酶家族。