닭의 가슴부위 및 다리부위의 골격근(骨格筋)에서 myofibril, actomyosin 및 myosin을 추출하고 ATPase activity(${mu}mole$ pi/mg protein/min)로서 나타낸 몇가지 생물학적(生物學的) 활성(活性)을 비교하였다. 가슴부위에서 추출한 actomyosin, myofibril 그리고 myosin의 $Mg^{+2}$-ATPase 활성(活性)은 0.05M KCl에서 0.80, 0.42, 0.40으로서 다리부위에서 추출한 단백질(蛋白質)의 활성(活性)인 0.69, 0.33, 0.28 보다 높았다. 가슴부위와 다리부위의 myosin의 ATPase 활성(活性)은 EDTA 농도보다 $Mg^{+2}$농도가 높아지면서 ATPase 활성(活性)을 1/10정도 저해(沮害)시켰고, $Ca^{+2}$ 농도는 $10^{-3}M$에서 400%까지 활성(活性)을 증가시켰다. 가슴부위와 다리부위에서 추출한 actomyosin의 용해되는 시점(始點)은 각각 0.1M KCl 및 0.15 M KCl이었고 myosin인 경우는 각각 0.25 M KCi 및 0.30 M KCl이었다.
Some biological activities showed as ATPase activity of myofibril, actomyosin and myosin extracted from chicken leg and pectoral skeletal muscle were investigated. The $Mg^{+2}$-ATPase activity at 0.05 M KCl were 0.82, 0.38 and 0.11 ${mu}mole$ Pi/mg protein/min. in actomyosin, myofibril and myosin from pectoral muscle while 0.71, 0.32 and 0.08 ${mu}mole$ Pi/mg protein/min. in actomyosin, myofibril and myosin from leg muscle. EDTA-ATPase activity at 0.6M KCl were 0.80, 0.42 and 0.40 ${mu}mole$ Pi/mg protein/min. in actomyosin, myofibril and myosin from pectoral muscle. In case of leg muscle, that activity was noted as 0.69, 0.33 and 0.28 ${mu}mole$e Pi/mg protein/min in proteins. ATPase activity of myosin from leg and pectoral muscle were inhibited in 10% at a higher concentration of $Mg^{+2}$ than molar concentration of EDTA, and the ATPase activity was increased to 400% compared with control at $10^{-3}M$ of $Ca^{+2}$. Actomyosin from pectoral muscle was solubilized at 0.1 M KCl above and that from leg muscle was solubilized at 0.15 M KCl above. In case of myosin, pectoral muscle was solubilized at 0.25M KCI above and leg muscle was solubilized at 0.30M KCl above.
