Characterization of two methanopterin biosynthesis mutants of Methylobacterium extorquens AM1 by use of a tetrahydromethanopterin bioassay.
نویسندگان
چکیده
An enzymatic assay was developed to measure tetrahydromethanopterin (H(4)MPT) levels in wild-type and mutant cells of Methylobacterium extorquens AM1. H(4)MPT was detectable in wild-type cells but not in strains with a mutation of either the orf4 or the dmrA gene, suggesting a role for these two genes in H(4)MPT biosynthesis. The protein encoded by orf4 catalyzed the reaction of ribofuranosylaminobenzene 5'-phosphate synthase, the first committed step of H(4)MPT biosynthesis. These results provide the first biochemical evidence for H(4)MPT biosynthesis genes in bacteria.
منابع مشابه
Biochemical characterization of a dihydromethanopterin reductase involved in tetrahydromethanopterin biosynthesis in Methylobacterium extorquens AM1.
During growth on one-carbon (C1) compounds, the aerobic alpha-proteobacterium Methylobacterium extorquens AM1 synthesizes the tetrahydromethanopterin (H4MPT) derivative dephospho-H4MPT as a C1 carrier in addition to tetrahydrofolate. The enzymes involved in dephospho-H4MPT biosynthesis have not been identified in bacteria. In archaea, the final step in the proposed pathway of H4MPT biosynthesis...
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 186 5 شماره
صفحات -
تاریخ انتشار 2004