Leul Melakeselam, Normand Philippe, Sellstedt Anita
Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, Sweden.
Int Microbiol. 2009 Mar;12(1):23-8.
Uptake hydrogenase is an enzyme that is beneficial for nitrogen fixation in bacteria. Recent studies have shown that Frankia sp. has two sets of uptake hydrogenase genes, organized in synton 1 and synton 2. In the present study, phylogenetic analysis of the structural subunits of hydrogenase syntons 1 and 2 showed a distinct clustering pattern between the proteins of Frankia strains that were isolated from different host plants and non-Frankia organisms. The structural subunits of hydrogenase synton 1 of Frankia sp. CpI1, Frankia alni ACN14a, and F. alni AvCI1 were grouped together while those of Frankia spp. CcI3, KB5, UGL140104, and UGL011102 formed another group. The structural subunits of hydrogenase synton 2 of F. alni ACN14a and Frankia spp. CcI3 and BCU110501 grouped together, but those of Frankia spp. KB5 and CpI1, F. alni ArI3, and F. alniAvCI1 comprised a separate group. The structural subunits of hydrogenase syntons 1 and 2 of Frankia sp. EAN1pec were more closely related to those of non-Frankia bacteria, i.e., Streptomyces avermitilis and Anaeromyxobacter sp., respectively, than to those of other Frankia strains, suggesting the occurrence of lateral gene transfer between these organisms. In addition, the accessory Hyp proteins of hydrogenase syntons 1 and 2 of F. alni ACN14a and Frankia sp. CcI3 were shown to be phylogenetically more related to each other than to those of Frankia EAN1pec.
摄取氢化酶是一种对细菌固氮有益的酶。最近的研究表明，弗兰克氏菌属有两组摄取氢化酶基因，分别组织在同 synton 1 和 synton 2 中。在本研究中，对氢化酶 synton 1 和 2 的结构亚基进行的系统发育分析表明，从不同宿主植物分离的弗兰克氏菌菌株的蛋白质与非弗兰克氏菌生物体之间存在明显的聚类模式。弗兰克氏菌属 CpI1、桤木弗兰克氏菌 ACN14a 和桤木弗兰克氏菌 AvCI1 的氢化酶 synton 1 的结构亚基聚在一起，而弗兰克氏菌属 CcI3、KB5、UGL140104 和 UGL011102 的结构亚基则形成另一组。桤木弗兰克氏菌 ACN14a 和弗兰克氏菌属 CcI3 及 BCU110501 的氢化酶 synton 2 的结构亚基聚在一起，但弗兰克氏菌属 KB5 和 CpI1、桤木弗兰克氏菌 ArI3 和桤木弗兰克氏菌 AvCI1 的结构亚基组成一个单独的组。弗兰克氏菌 EAN1pec 的氢化酶 synton 1 和 2 的结构亚基与非弗兰克氏菌，即阿维链霉菌和厌氧粘细菌的结构亚基的关系，分别比与其他弗兰克氏菌菌株的关系更密切，这表明这些生物体之间发生了横向基因转移。此外，桤木弗兰克氏菌 ACN14a 和弗兰克氏菌属 CcI3 的氢化酶 synton 1 和 2 的辅助 Hyp 蛋白在系统发育上彼此之间的关系比与弗兰克氏菌 EAN1pec 的关系更密切。
