쏘가리 젖산탈수소효소(EC 1.1.1.27, lactate dehydrogenase, LDH) $A_4$ 동위효소를 affinity chromatography 및 ultrafiltration으로 정제하였다. 정제된 LDH $A_4$ 동위효소의 분자량은 140.4 kDa이었고 등전점(pI)은 7.0이었다. 효소반응의 최적 pH는 7.5로 나타났다. 피루브산을 기질로 하였을 때 LDH $A_4$ 동위효소의 ${K_m}^{PYR}$값은 $4.86{ imes}10^{-5}$ M, $V_{max}$값은 13.31mM/min로 나타났다. LDH $A_4$ 동위효소의 역학실험은 쏘가리가 온수성어류라는 점을 보여주었고 정제된 LDH $A_4$ 동위 효소에 대한 항체는 변온 척추동물의 대사생리학적 특성을 연구하거나 여러 가지 병증의 진단에 유용하게 사용될 수 있을 것이다.
The lactate dehydrogenase (EC 1.1.1.27, LDH) $A_4$ isozyme in skeletal muscle of mandrin fish (Siniperca scherzeri) was successfully purified by affinity chromatography and ultrafiltration. The molecular weight of the purified LDH $A_4$ isozyme was 140.4 kDa and its isoelectric point (pI) was 7.0. Optimal pH for enzymatic reaction was 7.5. ${K_m}^{PYR}$ and $V_{max}$ value of the purified LDH $A_4$ isozyme were $4.86{ imes}10^{-5}$ M and 13.31 mM/min using pyruvate as a substrate, respectively. These kinetic properties of the purified LDH $A_4$ isozyme supported the fact that the mandrin fish was a warm-adapted species. The antibody against the purified LDH $A_4$ isozyme may be used in the metabolic physiological studies of ectothermic vertebrates and in the diagnosis of several human diseases.
