Occurrence of β-alanine-specific opine dehydrogenase in the muscle of the limpet Cellana grata Gould (Archaeogastropoda)

• Published in: Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology 1999-06, Vol.123 (2), p.125-136
• Main Authors: Kan-no, Nobuhiro, Sato, Minoru, Yokoyama, Takehiko, Nagahisa, Eizoh
• Format: Article
• Language: English
• Subjects: Amino Acid Oxidoreductases - chemistry; Amino Acid Oxidoreductases - isolation & purification; Amino Acids - analysis; Anaerobic glycolysis; Animals; beta-Alanine - metabolism; Cellana grata; Hydrogen-Ion Concentration; Kinetics; Marine; Mollusca - enzymology; Opine dehydrogenase; Oxidoreductases Acting on CH-NH Group Donors - chemistry; Oxidoreductases Acting on CH-NH Group Donors - isolation & purification; Oxidoreductases Acting on CH-NH Group Donors - metabolism; Peptide Mapping; Purification; Sequence Analysis; Serine Endopeptidases; Substrate Specificity; Tauropine dehydrogenase; β-Alanine; β-Alanopine; β-Alanopine dehydrogenase
• ISSN: 1096-4959; 0305-0491; 1879-1107
• DOI: 10.1016/S0305-0491(99)00031-0

The muscular tissues of the limpet Cellana grata exhibited β-alanopine dehydrogenase (β-AlDH) activity in addition to tauropine dehydrogenase (TaDH) activity and weak lactate dehydrogenase activity. Opine dehydrogenases (OpDHs) were purified, and two different types of OpDH, i.e. TaDHs and OpDHs showing β-AlDH activity, were isolated. From the specificity for amino acid and opine, OpDHs showing β-AlDH activity were concluded to be a true β-AlDH showing strict substrate specificity for β-alanine. Although the catalytic properties of β-AlDH and TaDH were essentially similar, they were distinct from each other with respect to the amino acid substrate specificity and the K m values. Apparent K m values (mM) for the preferred amino acid substrate, pyruvate, NADH, the preferred opine substrate, and NAD + were: 14.3 (β-alanine), 0.19, 0.032, 35.2 (β-alanopine), and 0.78 for β-AlDH; and 33.3 (taurine), 0.53, 0.076, 48.6 (tauropine), and 0.58 for TaDH, respectively. Great similarities were found between β-AlDH and TaDH with respect to molecular properties: molecular masses (both enzymes were monomeric proteins of approximately 40 000 Da), amino acid compositions, and N-terminal amino acid sequences (30 amino acid residues were identical). Partial similarities were also recognized between their lysyl endopeptidase maps. These results clearly show that β-alanine-specific OpDH, a true β-AlDH, is present in the limpet muscle.