Enzymatic degradation of cyclic 2,3-diphosphoglycerate to 2,3-diphosphoglycerate in Methanobacterium thermoautotrophicum

• Published in: Biochemistry (Easton) Vol. 31; no. 11; pp. 2926 - 2935
• Main Authors: Sastry, Musti V. Krishna, Robertson, Diane E, Moynihan, James A, Roberts, Mary F
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 24-03-1992
• Subjects: 2,3-Diphosphoglycerate; 550601 - Medicine- Unsealed Radionuclides in Diagnostics; BACTERIA; Bacteriology; BIOCHEMICAL REACTION KINETICS; BIODEGRADATION; Biological and medical sciences; CARBOHYDRATES; CARBON 12; CARBON 13; CARBON COMPOUNDS; CARBON DIOXIDE; CARBON ISOTOPES; CARBON OXIDES; CHALCOGENIDES; CHEMICAL REACTIONS; CHEMICAL SHIFT; Chromatography, Affinity; cyclic 2,3-diphosphoglycerate; DECOMPOSITION; Diphosphoglyceric Acids - metabolism; ENZYMATIC HYDROLYSIS; ESTERS; EVEN-EVEN NUCLEI; EVEN-ODD NUCLEI; Fundamental and applied biological sciences. Psychology; Hydrolases - chemistry; Hydrolases - isolation & purification; Hydrolases - metabolism; HYDROLYSIS; ISOTOPES; KINETICS; LIGHT NUCLEI; LIPIDS; LYSIS; MAGNETIC RESONANCE; Magnetic Resonance Spectroscopy; Metabolism. Enzymes; Methanobacterium - enzymology; METHANOGENIC BACTERIA; Microbiology; MICROORGANISMS; NUCLEAR MAGNETIC RESONANCE; NUCLEI; ORGANIC COMPOUNDS; ORGANIC PHOSPHORUS COMPOUNDS; OXIDES; Oxygen - pharmacology; OXYGEN COMPOUNDS; PHOSPHOLIPIDS; Potassium Chloride - pharmacology; RADIOLOGY AND NUCLEAR MEDICINE; REACTION KINETICS; RESONANCE; SOLVOLYSIS; Spectrophotometry; STABLE ISOTOPES; Temperature; Temperature; Archaeobacteria; Enzyme; Environmental factor; 2,3-Diphosphoglycerate; Enzymatic activity; Cyclic compound; Methanobacteriaceae; Enzymatic digestion; Bacteria; Kinetic parameter; Methanobacteriales; Methanobacterium thermoautotrophicum
• ISSN: 0006-2960; 1520-4995
• DOI: 10.1021/bi00126a012

2,3-Diphosphoglycerate (2,3-DPG) has been found to be the product of the enzymatic degradation of cyclic 2,3-diphosphoglycerate (cDPG) in the archaebacterium Methanobacterium thermoautotrophicum delta H. Although 2,3-DPG has not previously been detected as a major soluble component of M. thermoautotrophicum, large pools accumulated at an incubation temperature of 50 degrees C (below the optimum growth temperature of 62 degrees C). Under these conditions, cellular activity was significantly decreased; a return of the culture to the optimum growth temperature restored the 2,3-DPG pool back to original low levels and caused steady-state cDPG levels to increase again. While 13CO2-pulse/12CO2-chase experiments at 50 degrees C showed that the cDPG turned over, the appearance of 2,3-DPG at NMR-visible concentrations required at least 10 h. Production of 2,3-DPG in vivo was prevented by exposure of the cells to O2. The enzyme responsible for this hydrolysis of cDPG was purified by affinity chromatography and appears to be a 33-kDa protein. Activity was detected in the presence of oxygen and was enhanced by a solution of 1 M KCl, 25 mM MgCl2, and dithiothreitol. Both Km and Vmax have been determined at 37 degrees C; kinetics also indicate that in vitro the product, 2,3-DPG, is an inhibitor of cDPG hydrolysis. These findings are discussed in view of a proposed role for cDPG in methanogens.