Investigation of the nature of enzyme--coenzyme interactions in binary and ternary complexes of liver alcohol dehydrogenase with coenzymes, coenzyme analogues, and substrate analogues by ultraviolet absorption and phosphorescence spectroscopy.

Abstract:

:The difference spectra of binary and ternary complexes of horse liver alcohol dehydrogenase with oxidized and reduced nicotinamide adenine dinucleotides, nicotinamide 1,N6-ethenoadenine dinucleotide, and adenosine diphosphate ribose along with a number of substrate analogues have been measured. These spectra bear a very close resemblance to those obtained by perturbation of the coenzyme(s) and their analogues by acid, NaCl, dioxane, or tert-butyl alcohol. It is inferred that the coenzymes experience a combination of ionic and nonpolar environments at the adenine binding site of the enzyme. This is borne out by published X-ray crystallographic results. The phosphorescence spectra do not indicate the presence of ionized tyrosine in ternary complexes invovling enzyme, coenzyme, and substrate analogues. The ultraviolet spectra can be explained as arising from the perturbation of the coenzyme chromophores upon binding to the enzyme without having to invoke tyrosine ionization.

journal_name

Biochemistry

journal_title

Biochemistry

authors

Subramanian S,Ross JB,Ross PD,Brand L

doi

10.1021/bi00517a022

subject

Has Abstract

pub_date

1981-07-07 00:00:00

pages

4086-93

issue

14

eissn

0006-2960

issn

1520-4995

journal_volume

20

pub_type

杂志文章