Jadot M, Wattiaux R
Biochem J. 1985 Feb 1;225(3):645-8. doi: 10.1042/bj2250645.
The release by glycyl-L-phenylalanine 2-naphthylamide (Gly-L-Phe-2-NNap) of endocytosed invertase associated with the MLP fraction (sum of the M, L and P fractions [de Duve, Pressman, Gianetto, Wattiaux & Appelmans (1955) Biochem. J. 63, 604-617]) of rat liver was investigated and compared with the release of cathepsin C. The percentage of invertase released increases with time after the enzyme injection, whereas the release of cathepsin C is not influenced by this treatment and corresponds to 85-90% of the total activity of the enzyme. It takes about 2h to attain a similar release of both enzymes. The quantity of invertase releasable or not by Gly-L-Phe-2-NNap was plotted against the time after the injection. Results agree well with the hypothesis that unreleasable invertase is associated with a pre-lysosomal compartment, whereas releasable invertase is present in lysosomes. A kinetic analysis indicates that invertase enters the pre-lysosomal compartment with a zero-order rate constant of 0.48 unit/min per g fresh wt., and leaves this compartment with a first-order rate constant of 0.042 min-1.
研究了甘氨酰-L-苯丙氨酸2-萘酰胺（Gly-L-Phe-2-NNap）对大鼠肝脏中与MLP组分（M、L和P组分的总和[德·迪夫、普雷斯曼、贾内托、瓦蒂奥克斯和阿佩尔曼斯（1955年）《生物化学杂志》63卷，604 - 617页]）相关的内吞蔗糖酶的释放情况，并与组织蛋白酶C的释放进行了比较。注射酶后，蔗糖酶的释放百分比随时间增加，而组织蛋白酶C的释放不受该处理影响，且相当于该酶总活性的85 - 90%。两种酶达到相似的释放量大约需要2小时。将Gly-L-Phe-2-NNap可释放或不可释放的蔗糖酶量与注射后的时间作图。结果与以下假设非常吻合：不可释放的蔗糖酶与溶酶体前区室相关，而可释放的蔗糖酶存在于溶酶体中。动力学分析表明，蔗糖酶以0.48单位/分钟·克鲜重的零级速率常数进入溶酶体前区室，并以0.042分钟⁻¹的一级速率常数离开该区域。
