Related Experiment Video
Updated: Aug 15, 2026

Hyperpolarized 13C Metabolic Magnetic Resonance Spectroscopy and Imaging
Published on: December 30, 2016
[LDH and structural analogues of pyruvate (author's transl)]
Abstract:
Pyruvate related compounds have been tested for their active or inhibitory properties on LDH. Special structure features were needed for compounds to be bound to the enzyme active site. Pyruvate and the LDH molecule were bound by the interaction of the carboxyl group or its ester derivative, with the enzyme. Ethyl pyruvate seemed to behave as a substrate of the enzyme whereas acetophenone, ethyl acetoacetate and beta-oxoglutarate did not act as substrates or inhibitors of LDH. Phenyl pyruvate, alpha-oxoglutarate and L-mandelate are not substrates but inhibitors of the LDH. It seems that a structure having a carbonyl group in the alpha-position to the carboxyl is required for the binding of a compound to the LDH molecule. Glyoxylate alpha-oxobutyrate and alpha-oxovalerianate appear to be worse LDH substrates than pyruvate itself. This seems to suggest that the shortening or the extension of the pyruvate aliphatic chain induces a decrease of the affinity of the enzyme towards their substrate homologues.
Related Concept Videos
What is Glycolysis?
Cells make energy by breaking down macromolecules. Cellular respiration is the biochemical process that converts "food energy" (from the chemical bonds of macromolecules) into chemical energy in the form of adenosine triphosphate (ATP). The first step of this tightly regulated and intricate process is glycolysis. The word glycolysis originates from the Latin glyco (sugar) and lysis (breakdown). Glycolysis serves two main intracellular functions: generating ATP and generating...
Energy-requiring Steps of Glycolysis
Pyruvate Oxidation
First, the enzyme pyruvate dehydrogenase removes the carboxyl group from pyruvate and releases it as carbon dioxide. The stripped molecule is then oxidized and releases electrons, which are then picked up by NAD+...
Urea Cycle
Outcomes of Glycolysis
Cellular respiration can occur aerobically (with oxygen) or anaerobically (without oxygen). In the presence of oxygen, cellular respiration starts with glycolysis and continues with pyruvate oxidation, the...
Fates of Pyruvate
In aerobic organisms, pyruvate is metabolized via the citric acid cycle to produce reduced coenzymes NADH and FADH2. These coenzymes are then oxidized in the electron transport chain to produce ATP and, in the process, regenerate the NAD+ and FAD. As seen in some cell types and organisms, fermentation...

