title: A novel biosynthesis of medium chain length alpha-ketodicarboxylic acids in methanogenic archaebacteria.
abstract: Gas chromatographic-mass spectrometric analysis on the distribution of alpha-ketodicarboxylic acids in various bacteria determined that alpha-ketoglutarate and alpha-ketoadipate are widely distributed in all the bacteria examined, whereas alpha-ketopimelate and alpha-ketosuberate are found only in the methanogenic archaebacteria. Labeling experiments with stable isotopes indicated that each of these acids arises from alpha-ketoglutarate by repeated alpha-ketoacid chain elongation. The final product in this series of reactions, alpha-ketosuberate, serves in the methanogenic bacteria as the biosynthetic precursor to the 7-mercaptoheptanoic acid portion of 7-mercaptoheptanoylthreonine phosphate, a methanogenic coenzyme.
authors.affiliation: Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg 24061.
authors.forename: R H
authors.initials: RH
authors.lastname: White
mesh_terms: D000272:Adipates / Q000096:biosynthesis; D001105:Archaea / Q000378:metabolism*; D001419:Bacteria / Q000378:metabolism*; D002210:Caprylates; D003998:Dicarboxylic Acids / Q000096:biosynthesis*; D019605:Euryarchaeota / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D007651:Keto Acids / Q000096:biosynthesis*; D007656:Ketoglutaric Acids / Q000096:biosynthesis; D010867:Pimelic Acids / Q000096:biosynthesis
chemical_list: D000272:Adipates; D002210:Caprylates; D003998:Dicarboxylic Acids; D007651:Keto Acids; D007656:Ketoglutaric Acids; D010867:Pimelic Acids; C005738:suberic acid