Lara Beatriz, Ayala Juan A
Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain.
FEMS Microbiol Lett. 2002 Oct 29;216(1):23-32. doi: 10.1111/j.1574-6968.2002.tb11409.x.
The membrane topology of Escherichia coli FtsW, a 46-kDa essential protein, was analyzed using a set of 28 ftsW-alkaline phosphatase (ftsW-phoA) and nine ftsW-beta-lactamase (ftsW-bla) gene fusions obtained by in vivo and in vitro methods. The alkaline phosphatase activities or resistance pattern of cells expressing the FtsW-PhoA or FtsW-Bla fusions confirmed only eight out of 10 transmembrane segments predicted by computational methods. After comparison with the recent topology of Streptococcus pneumoniae FtsW, we could identify all the fusions in absolute agreement with the predicted model: N-terminal and C-terminal ends in the cytoplasm, 10 transmembrane segments and one large loop of 67 amino acids (E240-E306) located in the periplasm.
利用通过体内和体外方法获得的一组28个ftsW-碱性磷酸酶（ftsW-phoA）和9个ftsW-β-内酰胺酶（ftsW-bla）基因融合体，对大肠杆菌中一种46 kDa的必需蛋白FtsW的膜拓扑结构进行了分析。表达FtsW-PhoA或FtsW-Bla融合体的细胞的碱性磷酸酶活性或抗性模式仅证实了计算方法预测的10个跨膜区段中的8个。与肺炎链球菌FtsW最近的拓扑结构进行比较后，我们能够确定所有融合体与预测模型完全一致：N端和C端在细胞质中，10个跨膜区段和一个位于周质中的67个氨基酸（E240-E306）的大环。
