Coenzyme Interactions

S. Subramanian, J. B. A. Ross, L. Brand, and P. D. Ross, Investigation of the nature of enzyme-coenzyme interactions in binary and ternary complexes of liver alcohol dehydrogenase with coenzymes, coenzyme analogs, and substrate analogs by ultraviolet absorption and phosphorescence spectroscopy, Biochemistry 20, 4086-4093 (1981). 

Drug-Coenzyme Interactions Isoniazid and Pyridoxal Phosphate... 

Immobilized Derivatives of Cobalamins and Their Use as Affinity Adsorbents for a Study of Enzyme-Coenzyme Interaction... 

NAD. The several possibilities for Zn -NAD interaction have been reviewed. However, the wide range of techniques that have been applied have failed to give conclusive evidence for direct metal-coenzyme interaction. Many studies have been inconclusive or contradictory. On the other hand there is some positive evidence for the maintenance of a four-coordinate geometry for the metal in the binary complex. Thus the shape and intensity of the electronic spectrum of Co(c)2Zn(n)2-LADH (discussed below) are consistent with the expected tetrahedral structure for the catalytic metal ion. However, there are no major changes in the spectrum of the binary complex, suggesting that the four-coordinate structure is maintained and that the coenzyme does not bind to the metal. 

In the decarboxylation of pyruvate, the coenzyme interacts with pyruvic acid to form so-called active aldehyde, as shown below. 

Huhta, M. S., Chen, FI. P., Hemann, C., Hille, C. R., Marsh, E. N. (2001) Protein-coenzyme interactions in adenosylcobalamin-dependent glutamate mutase, Biochem. J. 355, 131-137. 

Solutions to the problem of continuous catalyst repair in artificial reaction chains are not apparent, but they lie buried in the chemistry of the coenzymes, which activate small carbon molecules. In the following, we briefly summarize the chemistry of some coenzymes. They are also mostly vitamins. This time we do not deal with electrons and protons, but with small, carbon-containing molecules such as carbon dioxide, formic acid, acetic acid, and a-amino acids. Some of these coenzymes interact very strongly with protein receptors, which also makes them useful in synkineses of reactive molecular complexes with peptides. 

Fig. 14. Structure and functional domains of an ur-reductase . Such an enzyme is thought to combine two or three nucleotide binding sites (which affect each other) with a dicysteine center in one polypeptide chain, and a metal-coordinated radical in another polypeptide, or coenzyme interaction of the two components may, but must not involve Mg or other ions...

Apart from hydrogen bonding, other molecular interactions such as the protein- ligand binding, enzyme-coenzyme interactions etc. are also studied by infrared spectroscopy. 

A. A. Gallo and H. Z. Sable (1974), Coenzyme interactions. VIII. C-NMR studies of thiamine and related compounds. J. Biol. Chem. 249, 1382-1389. 

Rosenberg, L.E. (1979), The inherited methylmalonic acidaemias A model system for the study of vitamin metabolism and apoenzyme-coenzyme interactions. The Milner Lecture Proc. 17th Anna. Meet. Soc. Study Inborn Errors Metab. Leeds, September, 1979. In the press, 1981. 

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