Postmorten Changes in the Myofibrillar Proteins of Alkaline and Acid Rigor Rabbit Muscle during Storage

사후강직형태에 따른 근원섬유 단백질의 이화학적 성질변화

This experiment was carried out to investigate some physico-chemical properties of myofibrillar proteins isolated from alkaline and acid rigor muscles of rabbit. The degree of fragmentation was about 0.35 at 3 days of postmortem in acid rigor muscle fiber, whereas it was only 0.3 at 7 days of postmortem in alkaline rigormuscle fiber. $Mg^{2+}$-activated ATPase activities of actomyosin were increased to the highest level at 1st day in acid rigor and at 3rd day in alkaline rigor muscle fiber. $Ca^{2+}$-activated ATPase activities of actomyosin were slightly increased at postmortem. $Mg^{2+}$-, and $Ca^{2+}$-activated ATPase activities were higher in alkaline rigor muscle than those in acid rigor muscle at postmortem. Solubility of actomyosin increased with postmortem but no differences were observed in rigor types. SDS-PAGE(sodium dodecyl sulfate polyacrylamide gel electrophoresis) band patterns of myofibrils did not show significant differences between rigor types, but newly 30.000 dalton proteins were appeared at 3 day postmortem in both rigor types.

산 강직근과 알카리 강직근의 사후 자장중 물리, 화학적 변화를 비교 검토하였다. 근섬유의 소편화도는 산강직근이 알카리 강직근에 비하여 저장 3일째부터 월등히 높았다. $Mg^{2+}$-ATPase 활성은 알카리 강직근이 저장 전기간 동안 산 강직근 보다 높았으며, 산 강직근은 저장 1일째, 알카리 강직근은 저장 3일째에 가장 높았다. $Ca^{2+}$-ATPase 활성에 있어서 산 강직근과 알카리 강직근 모두 전 저장기간 동안 약간 증가하는 경향이었으나 산 강직근은 알카리 강직근 보다 전기간 동안 활성도가 낮았다. Actomyosin의 용해성이나 myofibril의 전기영동상은 강직 형태에 따른 유의한 차이가 없었다.