Involvement of chlA, E, M, and N loci in Escherichia coli molybdopterin biosynthesis.
All molybdenum enzymes except nitrogenase contain a common molybdenum cofactor, whose organic moiety is a novel pterin called molybdopterin (MPT). To assist in elucidating the biosynthetic pathway of MPT, two MPT-deficient mutants of Escherichia coli K-12 were isolated. They lacked activities of the molybdenum enzymes nitrate reductase and formate dehydrogenase, did not reconstitute apo nitrate reductase from a Neurospora crassa nit-1 strain, and did not yield form A, a derivative of MPT. By P1 mapping, these two mutations mapped to chlA and chlE, loci previously postulated but never definitely shown to be involved in MPT biosynthesis. The two new mutations are in different genetic complementation groups from previously isolated chlA and chlE mutations and have been designated as chlM and chlN (closely linked to chlA and chlE, respectively). The reported presence of Mo cofactor activity in the chlA1 strain is shown to be due to in vitro synthesis of MPT through complementation between a trypsin-sensitive macromolecule from the chlA1 strain and a low-molecular-weight compound from the nit-l strain.[1]References
- Involvement of chlA, E, M, and N loci in Escherichia coli molybdopterin biosynthesis. Johnson, M.E., Rajagopalan, K.V. J. Bacteriol. (1987) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg
