Direct evidence for a coupling between synthesis and export of PhoS in E. coli
Résumé
The accumulation of pre‐PhoS under conditions of PhoS overproduction has been previously described. It is now demonstrated that during the induction of PhoS, a delay in the completion of polypeptide chain elongation can be detected. This delay is related to the extent of jamming of export sites by pre‐PhoS or by other exported proteins. These results suggest that a component required for completion of pre‐PhoS polypeptide becomes limiting, being titrated by the excess of nascent chains bearing signal peptides. This component thus probably acts at an early step in the export pathway.