Stabrovskaia V I, Braun A D
Tsitologiia. 1980 Apr;22(4):441-7.
A study has been made on changes of outflux, extractability and activity of phosphofructokinase (PPK) under the action of heating, and of urea on the frog's skeletal muscles and on their extracts. Under the action of heating on muscles, the decrease of PPK activity (to 35%) is first revealed 34--36 degress C, when decrease of excitability and the contracture are not yet detected, and the extractability of the total water-soluble protein does not change. At the start of contracture, and at the decrease of excitability (at 38 degrees C) PPK in the muscle loses its activity. The thermolability of PPK is the greatest one compared to all the enzymes investigated before. The data on the high thermolability of PPK are discussed in terms of the regulating role of PPK in glycolysis. The PPK activity of extracts of muscles altered by urea, during the action not accompanied by the death of muscles, does not change. At the irreversible disappearance of muscle excitability, PPK is inactivated. PPK in the cell is more stable to injuring agents than PPK in isolated state.
研究了加热以及尿素作用于青蛙骨骼肌及其提取物时，磷酸果糖激酶（PPK）的流出量、可提取性和活性的变化。在加热肌肉的作用下，当兴奋性降低和挛缩尚未被检测到时，在34 - 36摄氏度首先发现PPK活性降低（至35%），且总水溶性蛋白质的可提取性没有变化。在挛缩开始时以及兴奋性降低时（38摄氏度），肌肉中的PPK失去活性。与之前研究的所有酶相比，PPK的热稳定性是最大的。根据PPK在糖酵解中的调节作用讨论了PPK高热稳定性的数据。在尿素作用期间，肌肉提取物的PPK活性在不伴随肌肉死亡的情况下不变。在肌肉兴奋性不可逆消失时，PPK失活。细胞中的PPK比分离状态下的PPK对损伤剂更稳定。
