Medicine and Health Sciences Commons^™

Negative Cooperatively In The Binding Of 3-Aminopyridine Adenine Dinucleotide To L-Α-Glycero-3-Phosphate Dehydrogenase, David Wheeler

Chemistry & Biochemistry Theses & Dissertations

Glycerol-3-phosphate dehydrogenase catalyzes the reversible reaction:

NAD⁺ + G-3-P ⇌ NADH + DHAP + H⁺

The enzyme is found in organisms from E. coli to man. The primary function of the enzyme varies from organism to organism. Depending on the metabolism of the organism, the enzyme may function primarily to generate G-3-P for lipid (in organisms with a highly aerobic biosynthesis metabolism), or it may function primarily to produce NAD⁺ to support glycolysis. Complex multicellular organisms possess tissue specific isozymes of GPDH whose kinetic parameters reflect the relative importance of G-3-P and NAD⁺ production in various …

Investigation Of The Coenzyme Binding Site Of Lactate Dehydrogenase From Chicken Muscle, Jia-Hwei Lin

Chemistry & Biochemistry Theses & Dissertations

Investigation of the coenzyme binding site of lactate dehydrogenase was approached by using coenzyme analogs. Inhibition studies of this enzyme using n-alkylphosphates as coenzyme analogs were performed with a fluorometric method. The results showed that all of the n-alkylphosphates were competitive inhibitors with respect to NAD⁺.

The n-alkyl-ADPs were synthesized from AMP and dicycloheaylammonium salts of n-alkylphosphates. The synthetic compounds were subjected to NMR spectroscopic studies, thin layer chromatography and determination of the ratio of adenosine moiety to phosphate groups. The results indicated that the synthetic compounds were n-alkyl-ADPs.

These synthetic compounds were used as coenzyme analogs in …

Kinetic And Binding Studies On L-∝-Glycerophosphate Dehydrogenase, Paul Richard Rosevear

Chemistry & Biochemistry Theses & Dissertations

The properties of the coenzyme, NAD, binding site of chicken muscle L-∝-glycerophosphate dehydrogenase were studied. Adenosine monophosphate, adenosine diphosphate and adenosine diphosphoribose were sha.vn to inhibit the enzyme competitively with respect to NAD. The presence of adenosine, pyrophosphate and ribose regions in the coenzyme binding site of the enzyme was suggested by the inhibitor constants obtained for these compounds.

Disodium monoalkyl phosphates, n-butyl to n-dodecyl phosphate, inclusive, were also shown to inhibit the L-∝-glycerophosphate dehydrogenase catalized reaction competitively with respect to NAD. A positive chain length effect was observed in the binding of these compounds to the enzyme, suggesting the …