从纯化的部件组成的膜组件. 我. 我. 我. 我. 我. 我. 我. 隔离的M13前层不需要核糖体或可溶性蛋白质通过膜进行处理
Cell
|August 1, 1981
概括
胆菌M13外套蛋白质被合成为一种名为procoat的前体. 净化后的毛皮可以通过领导酶和膜被加工成毛皮蛋白,这表明不需要额外的因素.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 蛋白质生物化学 蛋白质生物化学
背景情况:
- Coliphage M13外套蛋白是一种不可分割的膜蛋白.
- 它被合成为一种可溶的前体,procoat,带有领导序列.
- 在组装成病毒时,Procoat被加工成成熟的外套蛋白质.
研究的目的:
- 为了分离和表征净化前层.
- 为了研究皮加工所需的酶和条件.
- 确定是否需要额外的可溶性因子来插入膜,并将前层转化为涂层蛋白.
主要方法:
- 在M13感染的细胞RNA的体外翻译产生35S标记的prokoat.
- 使用有机溶剂提取和 Sephadex LH-60 凝过,隔离放射化学纯的 procoat.
- 使用纯化的procoat进行领导酶和领导酸酶活性的测试.
- 通过纯化的大肠杆菌领导酶和逆转的大肠杆菌内膜囊泡来处理前层.
主要成果:
- 在放射化学上纯净的procoat被成功分离出来.
- 领袖酶和膜的Procoat处理受Mg2+的影响.
- 在特定条件下 (低离子强度,性pH,洗剂) 隔离的前层是可溶的.
- 纯化的前层被纯化的领导化酶和大肠杆菌内膜囊泡切割成涂层蛋白.
结论:
- 净化前涂料的加工模仿了原始提取物中的处理,这表明没有其他可溶性因素是必不可少的.
- 这提供了强有力的证据,表明蛋白质合成不需要用于前层膜组装和转化.
- 隔离的procoat的特性与其作为膜前体的作用相一致.
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