Kuznetsov Stepan, Milenkin Alexander, Antonov Ivan
Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia.
Institute of Bioengineering, Research Center of Biotechnology, Russian Academy of Science, 117312 Moscow, Russia.
Microorganisms. 2022 Jun 11;10(6):1200. doi: 10.3390/microorganisms10061200.
Today, hundreds of prokaryotic species are able to synthesize chlorophyll and cobalamin (vitamin B12). An important step in the biosynthesis of these coenzymes is the insertion of a metal ion into a porphyrin ring. Namely, Mg-chelatase ChlIDH and aerobic Co-chelatase CobNST are utilized in the chlorophyll and vitamin B12 pathways, respectively. The corresponding subunits of these enzymes have common evolutionary origin. Recently, we have identified a highly conserved frameshifting signal in the gene. This unusual regulatory mechanism allowed production of both the small and the medium chelatase subunits from the same gene. Moreover, the gene appeared early in the evolution and could be at the starting point in the development of the chlorophyll and B12 pathways. Here, we studied the possible coevolution of these two pathways through the analysis of the chelatase genes. To do that, we developed a specialized Web database with comprehensive information about more than 1200 prokaryotic genomes. Further analysis allowed us to split the coevolution of the chlorophyll and B12 pathway into eight distinct stages.
如今，数百种原核生物能够合成叶绿素和钴胺素（维生素B12）。这些辅酶生物合成过程中的一个重要步骤是将金属离子插入卟啉环。具体而言，镁螯合酶ChlIDH和好氧钴螯合酶CobNST分别用于叶绿素和维生素B12的合成途径。这些酶的相应亚基具有共同的进化起源。最近，我们在该基因中发现了一个高度保守的移码信号。这种不同寻常的调控机制使得同一个基因能够产生小的和中等大小的螯合酶亚基。此外，该基因在进化过程中出现得较早，可能是叶绿素和维生素B12合成途径发展的起点。在此，我们通过分析螯合酶基因来研究这两条途径可能的共同进化。为此，我们开发了一个专门的网络数据库，其中包含了1200多个原核生物基因组的全面信息。进一步的分析使我们能够将叶绿素和维生素B12合成途径的共同进化分为八个不同阶段。
