Rasulova F S, Dergousova N I, Starkova N N, Melnikov E E, Rumsh L D, Ginodman L M, Rotanova T V
Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow.
FEBS Lett. 1998 Aug 7;432(3):179-81. doi: 10.1016/s0014-5793(98)00859-x.
Selective protein degradation is an energy-dependent process performed by high-molecular-weight proteases. The activity of proteolytic components of these enzymes is coupled to the ATPase activity of their regulatory subunits or domains. Here, we obtained the proteolytic domain of Escherichia coli protease Lon by cloning the corresponding fragment of the lon gene in pGEX-KG, expression of the hybrid protein, and isolation of the proteolytic domain after hydrolysis of the hybrid protein with thrombin. The isolated proteolytic domain exhibited almost no activity toward protein substrates (casein) but hydrolyzed peptide substrates (melittin), thereby confirming the importance of the ATPase component for protein hydrolysis. Protease Lon and its proteolytic domain differed in the efficiency and specificity of melittin hydrolysis.
选择性蛋白质降解是一个由高分子量蛋白酶执行的能量依赖过程。这些酶的蛋白水解成分的活性与其调节亚基或结构域的ATP酶活性相关联。在此，我们通过将lon基因的相应片段克隆到pGEX-KG中，表达融合蛋白，并在用凝血酶水解融合蛋白后分离蛋白水解结构域，从而获得了大肠杆菌蛋白酶Lon的蛋白水解结构域。分离出的蛋白水解结构域对蛋白质底物（酪蛋白）几乎没有活性，但能水解肽底物（蜂毒肽），从而证实了ATP酶成分对蛋白质水解的重要性。蛋白酶Lon及其蛋白水解结构域在蜂毒肽水解的效率和特异性上有所不同。
