Polypeptide binding of Escherichia coli FtsH (HflB)
Polypeptide binding of Escherichia coli FtsH (HflB)
复制标题
大肠杆菌 FtsH (HflB) 的多肽结合
作者：
Y. Akiyama;M. Ehrmann;A. Kihara;Koreaki Ito
大肠杆菌FtsH蛋白是一种膜结合和ATP依赖的蛋白酶。在这项研究中，我们描述了ATP依赖性的FtsH构象变化以及该蛋白的多肽结合能力。在ATP存在下，一个33kda的FtsH片段对胰蛋白酶产生抗性。ATP和ATPγ s在37°C时阻止了洗涤剂溶解的FtsH - His6 - Myc的自聚集，再次表明ATP的结合诱导了FtsH的构象变化。亲和层析表明，FtsH - His6 - Myc可以与变性碱性磷酸酶（PhoA）结合，但不能与天然酶结合。变性PhoA也阻止了FtsH的聚集，这两种蛋白通过蔗糖梯度共同沉积。也证实了FtsH - His6 - Myc与洗涤剂溶解的SecY之间的结合。虽然FtsH结合的SecY被进一步处理以进行ATP依赖的蛋白水解，但FtsH结合的PhoA却没有。因此，FtsH与变性PhoA的结合是与蛋白水解分离的。过量生产的FtsH显著增加了MalF-PhoA杂交蛋白PhoA片段的细胞质定位，其中一个带电残基被引入跨膜片段。因此，FtsH的变性PhoA结合也可能在体内发生。
The Escherichia coli FtsH protein is a membrane‐bound and ATP‐dependent protease. In this study, we describe ATP‐dependent conformational changes in FtsH as well as a polypeptide binding ability of this protein. A 33 kDa segment of FtsH became trypsin resistant in the presence of ATP. ATP and ATPγS prevented self‐aggregation of detergent‐solubilized FtsH‐His6‐Myc at 37°C, again suggesting that the binding of ATP induces a conformational change in FtsH. Affinity chromatography showed that FtsH‐His6‐Myc can associate with denatured alkaline phosphatase (PhoA) but not with the native enzyme. Denatured PhoA also prevented the aggregation of FtsH, and these two proteins co‐sedimented through a sucrose gradient. Binding between FtsH‐His6‐Myc and detergent‐solubilized SecY was also demonstrated. Although FtsH‐bound SecY was processed further for ATP‐dependent proteolysis, FtsH‐bound PhoA was not. Thus, FtsH association with denatured PhoA is uncoupled from proteolysis. Overproduction of FtsH significantly increased the cytoplasmic localization of the PhoA moiety of a MalF–PhoA hybrid protein, in which a charged residue had been introduced into a transmembrane segment. Thus, denatured PhoA binding of FtsH may also occur in vivo.
DOI：
10.1073/pnas.94.5.1896
发表时间：
1997-03-04
影响因子：
11.1
作者：
Hughes, EA;Hammond, C;Cresswell, P
通讯作者：
Cresswell, P
DOI：
10.1073/pnas.93.12.5808
发表时间：
1996-06-11
影响因子：
11.1
作者：
Rohrwild, M;Coux, O;Goldberg, AL
通讯作者：
Goldberg, AL
来自大肠杆菌的 ATP 依赖性蛋白酶 La (lon)。
影响因子：
--
作者：
Goldberg,AL;Moerschell,RP;Chung,CH;Maurizi,MR
通讯作者：
Maurizi,MR