A self-regulated high-copy number plasmid containing chloramphenicol resistant gene, for the production of recombinant proteins under the regulation of bacteriophage λpL promoter, was constructed. The designed 5024 base pair expression plasmid contained a heat sensitive repressor cI857 coding gene to regulate the function of λpL promoter under heat shock induction. Using the constructed vector,...

Six independent secretion-defective mutations were found that result in failure to release protein from the membrane into the periplasmic space of Salmonella typhimurium after removal of the signal peptide. The mutant protein is found in a membrane-bound form accessible to trypsin added to intact spheroplasts. The phenotype of these mutations supports the existence in general of an intermediate...

A protein which binds to either single-stranded or double-stranded deoxyribonucleic acid (DNA) but not to ribonucleic acid has been isolated by osmotic shock treatment of growing cells. This periplasmic protein differs from the principal intracellular binding protein in its greater thermolability and by the absence of salt-induced cooperativity in its interaction with single-stranded DNA. Certa...