NMR studies of fructose-1,6-bisphosphate aldolase from E. coli

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:6523398

Szwergold, B S

Previous NMR studies of intact E. coli showed that during steady state anaerobic catabolism of glucose the main glycolytic intermediate detectable in these cells is fructose-1,6-bisphosphate (FBP), levels of which remain constant while the levels of glucose, lactate and succinate vary considerably. Upon feeding these cells glucose labeled with /sup 13/C at the C1 or C6 position, the level of scrambling of label between the C1 and C6 positions of FBP was low suggesting that the FBP-aldolase reaction is far from equilibrium. In order to account for these observations, a study was undertaken on FBP-aldolase from this organism. This enzyme is a dimeric Zn/sup + +/ metalloenzyme with a M/sub r/ of 80,000. It was purified in gram quantities from an overproducer strain and was characterized by standard biochemical techniques prior to the NMR studies. /sup 13/C NMR experiments were conducted using (2-/sup 13/C)dihydroxyacetone phosphate (DHAP) and (2,5-/sup 13/C)fructose-1,6-biphosphate (FBP). Since these substrates can exist in solution in a number of interconvertible forms, the initial experiments determined the relative amounts of these forms and the rates of their interconversion. Subsequently, NMR experiments with the purified enzyme were conducted. Based upon these results, the author concludes that in E. coli the FBP-alkolase reaction appears to be the rate limiting step of anaerobic glycolysis.

• Research Organization: Columbia Univ., New York (USA)
• OSTI ID: 6523398
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ALDEHYDE-LYASES
ALDOLASE
BACTERIA
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL PATHWAYS
CARBOHYDRATES
CARBON 13
CARBON ISOTOPES
CARBON-CARBON LYASES
ENZYMES
ESCHERICHIA COLI
EVEN-ODD NUCLEI
HEXOSES
ISOTOPES
KINETICS
LIGHT NUCLEI
LYASES
MAGNETIC RESONANCE
MICROORGANISMS
MOLECULAR STRUCTURE
MONOSACCHARIDES
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ORGANIC COMPOUNDS
REACTION KINETICS
RESONANCE
SACCHARIDES
STABLE ISOTOPES