Substrate Specificities of Wild and Mutated Farnesyl Diphosphate Synthases from<i>Bacillus Stearothermophilus</i>with Artificial Substrates
作者:Masahiko NAGAKI、Minori NAKADA、Tohru MUSASHI、Jun KAWAKAMI、Norimasa OHYA、Masayo KURIHARA、Yuji MAKI、Tokuzo NISHINO、Tanetoshi KOYAMA
DOI:10.1271/bbb.70067
日期:2007.7.23
To determine the substrate specificities of wild and mutated types of farnesyl diphosphate (FPP) synthases from Bacillus stearothermophilus, we examined the reactivities of 8-hydroxygeranyl diphosphate (HOGPP) and 8-methoxygeranyl diphosphate (CH3OGPP) as allylic substrate homologs.The wild-type FPP synthase reaction of HOGPP (and CH3OGPP) with isopentenyl diphosphate (IPP) gave hydroxyfarnesyl- (and methoxyfarnesyl-) diphosphates that stopped at the first stage of condensation.On the other hand, with mutated type FPP synthase (Y81S), the former gave hydroxygeranylgeranyl diphosphate as the main double-condensation product together with hydroxyfarnesyl diphosphate as a single-condensation product and a small amount of hydroxygeranylfarnesyl diphosphate as a triple-condensation product. Moreover, the latter gave a double-condensation product, methoxygeranylgeranyl diphosphate, as the main product and only a trace of methoxyfarnesyl diphosphate was obtained.
为了确定来自嗜热脂肪芽孢杆菌的野生型和突变型法尼基二磷酸 (FPP) 合酶的底物特异性,我们检查了 8-羟基香叶基二磷酸 (HOGPP) 和 8-甲氧基香叶基二磷酸 (CH3OGPP) 作为烯丙基底物同系物的反应性。 HOGPP(和CH3OGPP)与异戊烯基二磷酸(IPP)的FPP合酶反应产生羟基法呢基-(和甲氧基法呢基-)二磷酸,该反应在缩合的第一阶段停止。另一方面,对于突变型FPP合酶(Y81S),前者产生羟基香叶基香叶基二磷酸为主要双缩合物,羟基法尼基二磷酸为单缩合物,少量羟基香叶基法尼基二磷酸为三重缩合物。此外,后者得到双缩合产物甲氧基香叶基香叶基二磷酸酯作为主要产物,仅得到痕量的甲氧基法呢基二磷酸酯。