Send to

Choose Destination
Eur J Biochem. 1984 Sep 17;143(3):499-505.

Normal precursors of periplasmic proteins accumulated in the cytoplasm are not exported post-translationally in Escherichia coli.


Hyperproduction of phosphate-binding protein, PhoS, in strains carrying a multicopy plasmic containing the phoS gene, resulted in saturation of export sites. As a consequence, pre-PhoS was accumulated both in the inner membrane and in the cytoplasm. This was evidenced both in electron-microscopy and after cell fractionation. Only the membrane-associated precursor could be matured and exported. The signal sequence of the cytoplasmic pre-PhoS was slowly degraded. It was first cleaved about in its middle and then completely removed. Electron microscope studies demonstrated that the cytoplasmic pre-PhoS cannot be exported post-translationally.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center