Nat. Chem. Biol.: new progress in natural synthesis and biological function of cobalamin

The cobalamin family, represented by vitamin B 12, is one of the most complex nonpolymeric macromolecules in nature As a coenzyme factor necessary for many functional proteins, cobalamin plays an important role in maintaining the basic physiological and biochemical metabolism of cells (for example, DNA synthesis, methionine synthesis) The compounds of cobalamin family have complex molecules, but their domains are relatively conservative The structural differences of vitamin B 12 and other cobalamin analogues mainly depend on the structure of their lower bases There are as many as 16 kinds of low complex structures in known natural cobalamin analogues However, little attention has been paid to the structural diversity of cobalamin analogues and their biological functions Natural cobalamin and its low ligand structure (source: nature Chemistry Biology) In recent years, Yan Jun, the leader of the young innovative team of environmental organic pollution and remediation in the Key Laboratory of pollution ecology and environmental engineering, Chinese Academy of Sciences, and Yan Jun, a researcher of the environmental microbial ecology group of Shenyang Institute of Applied Ecology, Chinese Academy of Sciences, found that different cobalt analogues seriously affected the development of dechlorinated bacteria Growth and metabolic activity provide evidence for the correlation between the structure and function of cobalamin, and a new viewpoint is put forward that the difference in biological function of cobalamin mainly depends on the structure of its low ligand Based on this theory, Yan Jun and Professor Frank L ö ffler from the University of Tennessee and Oak Ridge National Laboratory in the United States and Professor Elizabeth Edwards from the University of Toronto in Canada have carried out research on the synthesis pathway, structure and biological function of cobalamin in dechlorinating bacteria cells The coenzyme factor (source: nature Chemistry Biology) of tetrachloroethylene dechlorination enzyme of Desulfitobacterium was isolated and identified by non denatured blue gel electrophoresis, mass spectrometry and proteomic analysis This international cooperative study was based on the study of Desulfitobacterium, the chromatogram, 15 A new kind of cobalamin analogue, unsubstituted purine and cobalamin, has been found by means of N-isotope labeling and nuclear magnetic analysis It is reported for the first time that unsubstituted purine, a rare biomolecule, can be used as a low-level coordination compound of natural cobalamin to support the growth and dechlorination activity of dechlorinating bacteria desirfitobacterium In this study, we used non denaturing blue gel electrophoresis and proteomic analysis to separate unsubstituted purinocobalamin from tetrachloroethylene dechlorinase with catalytic activity, which completely proved that the main function of unsubstituted purinocobalamin is to catalyze reductive dechlorination as coenzyme factor of tetrachloroethylene dechlorinase This research result fills up the blank in the field of cobalamin biosynthesis in the world, and endows the new biological function of unsubstituted purine The diversity of low-level complexes of cobalamin and its regulatory mechanism for the growth and activity of dechlorinating bacteria can provide a new strategy for in situ bioremediation of organochlorine pollutants in anaerobic environment (for example, groundwater environment) Relevant research content was published in nature chemical biology 14, 8-14 (2018) under the title of "purinyl cobamide is a native prosthetic group of reductive dehalogenases" Researcher Yan Jun of Shenyang Institute of ecology is the first author and co corresponding author of the above article Thesis link: https://www.nature.com/articles/nchembio.2512 homepage of the research group: wrhjwsw.iae.ac.cn/team researcher Yan Jun (source: Shenyang Institute of Ecology)