Purine metabolism by Methanococcus vannielii

Journal Article · Thu May 01 04:00:00 EDT 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6991243

DeMoll, E; Tsai, L

During studies of biosynthesis of novel cofactors in Methanococcus vannielii, it was discovered that guanine and xanthine are degraded by extracts of this organism. Using labeled substrates it was shown that uric acid, guanine, and hypoxanthine are converted to xanthine, which is then degraded in a manner similar to that described by Rabinowitz and Barker for clostridia. Extracts of M. vannielii convert the 2-, 6-, and 8-carbon atoms of xanthine to CO/sub 2/. It appears that the 8-carbon is initially lost as formate, which is then oxidized to CO/sub 2/ by the endogenous formate dehydrogenase. Enzyme preparations exposed to oxygen failed to convert (/sup 14/C)xanthine or (/sup 14/C)guanine either to CO/sub 2/ or to a form not adsorbed to charcoal. This oxygen inhibition could be reversed by treatment with dithiothreitol. Extracts exposed to oxygen apparently fail to carry out the initial step in xanthine degradation. The overall reaction for the degradation of guanine or xanthine is inhibited by EDTA and this inhibition is reversed by supplements of Mn/sup 2 +/ or Fe/sup 2 +/. Based on these studies, it was shown that uric acid, guanine, hypoxanthine, or xanthine could serve as sole nitrogen source for growth of the organism.

• Research Organization: National Institutes of Health, Bethesda, MD
• OSTI ID: 6991243
• Report Number(s): CONF-8606151-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Vol. 45:6; ISSN FEPRA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
550701 -- Microbiology-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINES
AROMATICS
AZAARENES
BACTERIA
CARBON 14 COMPOUNDS
CATIONS
CHARGED PARTICLES
ENZYMES
GROWTH
GUANINE
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
IONS
IRON COMPOUNDS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MANGANESE COMPOUNDS
METABOLISM
METHANOTROPHIC BACTERIA
MICROORGANISMS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
OXIDOREDUCTASES
PURINES
TRACER TECHNIQUES
TRANSITION ELEMENT COMPOUNDS
URIC ACID
XANTHINES