Subcellular localization of a PhoE‐LacZ fusion protein in E. coli by protease accessibility experiments reveals an inner‐membrane‐spanning form of the protein

FEBS Letters

Tommassen, Jan¹  de Kroon, Toon¹ 

[1] Department of Molecular Cell Biology and Institute for Molecular Biology, State University, Transitorium 3, Padualaan 8, Utrecht, The Netherlands

关键词: Outer membrane protein;    Protein export;    Hybrid protein;    (E. coli);   

DOI  :  10.1016/0014-5793(87)80930-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Protease accessibility experiments were employed to localize a PhoE-LacZ hybrid protein, encompassing a large N-terminal fragment of the outer membrane PhoE protein of E. coli, fused to β-galactosidase, at the subcellular level. In previous studies, this protein was shown to co-fractionate with the outer membrane, whereas immunocytochemical methods suggested a cytoplasmic location. The present results confirm the latter localization. Moreover, it appears that a minor amount of hybrid protein spans the inner membrane, with the PhoE moiety in the periplasm and the β-galactosidase moiety in the cytoplasm. These membrane-spanning proteins might be responsible for the lethal jamming of the export machinery, observed upon induction of synthesis of the protein.

【 授权许可】

Unknown