Genetic basis of opine dehydrogenase activities in the Pacific oyster, Crassostrea gigas

• Published in: Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology Vol. 121; no. 3; pp. 251 - 255
• Main Authors: Manchenko, G.P, McGoldrick, D.J, Hedgecock, D
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 1998
• Subjects: Alanopine dehydrogenase; Allozyme electrophoresis; Crassostrea gigas; Enzyme classification; Isozymes; Opine dehydrogenases; Strombine dehydrogenase; Substrate specificity; Strombine dehydrogenase; Enzyme classification; Opine dehydrogenases; Substrate specificity; Isozymes; Allozyme electrophoresis; Alanopine dehydrogenase; Crassostrea gigas
• ISSN: 1096-4959; 1879-1107
• DOI: 10.1016/S0305-0491(98)10096-2

Two polymorphic gene loci coding for enzyme proteins responsible for multiple opine dehydrogenase activities are expressed in the adductor muscle of the Pacific oyster,
Crassostrea gigas. One locus,
Strdh(
Alpdh-1), codes for an isozyme that demonstrates highest catalytic activity with glycine, but is also capable of using
α-
l-alanine,
l-serine and
β-alanine as substrates. The second locus,
Alpdh-
2, codes for an isozyme specific to
α-
l-alanine. Electrophoretic gels stained using
α-
l-alanine as substrate reveal presence of both isozymes in adductor muscle tissues. The STRDH(ALPDH-1) isozyme alone is detected in adductor muscle, with glycine as substrate, whereas only ALPDH-2 is detected in hepatopancreas, mantle and gill tissues with
α-
l-alanine. Only two enzyme proteins are responsible for multiple opine dehydrogenase activities in the adductor muscle of the oyster. The value of gene-enzyme specific allozyme patterns for identification of, and discrimination between, enzyme proteins possessing broad substrate specificity is briefly discussed.