Export defect adjacent to the processing site of staphylococcal nuclease is suppressed by a prlA mutation.
AUTOR(ES)
Liss, L R
RESUMO
Plasmids have been constructed in which the Escherichia coli alkaline phosphatase promoter and signal sequence have been fused to the staphylococcal nuclease gene to promote the high-level expression and secretion of this gene product in E. coli. We determined that the first amino acid residue after the signal sequence can determine whether this protein was processed and exported to the periplasmic space. Fractionation and protease accessibility studies were used to show that the export-defective, nuclease precursor is internal to the cytoplasmic membrane barrier of the cell. Furthermore, this export defect was suppressed in a strain containing a prlA mutation. These findings are novel in that this region of the polypeptide chain has been implicated in processing but not export and that prlA mutations have not been previously known to suppress such defects.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=214342Documentos Relacionados
- A signal sequence is not required for protein export in prlA mutants of Escherichia coli.
- Site-specific antibodies against the PrlA (secY) protein of Escherichia coli inhibit protein export by interfering with plasma membrane binding of preproteins.
- Distinct mutation sites in prlA suppressor mutant strains of Escherichia coli respond either to suppression of signal peptide mutations or to blockage of staphylokinase processing.
- Novel prlA alleles defective in supporting staphylokinase processing in Escherichia coli.
- prlA suppression of defective export of maltose-binding protein in secB mutants of Escherichia coli.