Biosynthesis of Menaquinones. Enzymatic Prenylation of l, 4-Dihydroxy-2-Naphthoate by Micrococcus luteus Membrane Fractions1
作者:Yukiko SAITO、Kyozo OGURA
DOI:10.1093/oxfordjournals.jbchem.a133337
日期:1981.4
l,4-Dihydroxy-2-naphthoate: polyprenyltransferase was detected in the membrane fraction from Micrococcus luteus. The specificity of the enzyme was so tolerant as regards the prenyl-donating substrate that prenyl pyrophosphates ranging in chain length from C15 to C45 were active as substrates. The monophosphate esters were also active, though the reactivities were much lower than those of the corresponding pyrophosphates. The enzyme showed rigorous specificity with respect to the aromatic substrate. Neither 1,4-dihydroxynaphthalene nor its 2-methyl derivative was active at all. l,4-Dihydroxy-3-methyl-2-naphthoate could be prenylated to afford menaquinone, but the reactivity was much less than that of its demethyl derivative. These results support the view that menaquinone biosynthesis involves the prenylation of 1,4-dihydroxy-2-naphthoate prior to decarboxylation or methylation.
l,4-二羟基-2-萘甲酸酯:在黄色微球菌的膜部分中检测到了聚烯基转移酶。该酶对烯基供体底物的特异性非常强,C15至C45的烯基焦磷酸盐都可以作为活性底物。单磷酸酯也是活性底物,但反应性远低于相应的焦磷酸盐。该酶对芳香族底物表现出严格的特异性。1,4-二羟基萘及其2-甲基衍生物均不具有活性。l,4-二羟基-3-甲基-2-萘甲酸酯可以被烯基化,生成甲萘醌,但反应性远低于其脱甲基衍生物。这些结果支持了这样的观点,即甲萘醌的生物合成涉及在脱羧或甲基化之前对1,4-二羟基-2-萘甲酸酯进行烯基化。