Marani Paola, Wagner Samuel, Baars Louise, Genevaux Pierre, de Gier Jan-Willem, Nilsson Ingmarie, Casadio Rita, von Heijne Gunnar
Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.
Protein Sci. 2006 Apr;15(4):884-9. doi: 10.1110/ps.051889506. Epub 2006 Mar 7.
Many new Escherichia coli outer membrane proteins have recently been identified by proteomics techniques. However, poorly expressed proteins and proteins expressed only under certain conditions may escape detection when wild-type cells are grown under standard conditions. Here, we have taken a complementary approach where candidate outer membrane proteins have been identified by bioinformatics prediction, cloned and overexpressed, and finally localized by cell fractionation experiments. Out of eight predicted outer membrane proteins, we have confirmed the outer membrane localization for five-YftM, YaiO, YfaZ, CsgF, and YliI--and also provide preliminary data indicating that a sixth--YfaL--may be an outer membrane autotransporter.
最近，通过蛋白质组学技术已鉴定出许多新的大肠杆菌外膜蛋白。然而，当野生型细胞在标准条件下生长时，低表达蛋白和仅在特定条件下表达的蛋白可能无法被检测到。在此，我们采用了一种互补方法，通过生物信息学预测来鉴定候选外膜蛋白，进行克隆和过表达，最后通过细胞分级分离实验对其进行定位。在八个预测的外膜蛋白中，我们已证实五个蛋白——YftM、YaiO、YfaZ、CsgF和YliI——定位于外膜，并且还提供了初步数据表明第六个蛋白——YfaL——可能是一种外膜自转运蛋白。
