Stability and function of the signal peptide of the pCloDF13-derived bacteriocin release protein.
The pCloDF13-derived bacteriocin release protein (BRP) is synthesized as a prelipoprotein with a signal peptide which remains stable after processing. This signal peptide accumulates in the cytoplasmic membrane and is, together with the mature BRP, required for efficient release of cloacin DF13. We investigated the structural requirements for stability of the BRP signal peptide by constructing hybrid signal peptides consisting of parts of the BRP and Lpp signal peptides. Signal peptide stability was investigated by pulse-labelling and pulse-chase experiments. To study the functioning of the BRP signal peptide, the hybrid constructs were tested for their ability to promote BRP-mediated cloacin DF13-release and their ability to affect the viability of the host cells. The results obtained suggest that the N-terminal part of the BRP signal peptide together with the C-terminal alanine residue are important for stability. When expressed as a separate entity, all mutant signal peptides that contain a part of the BRP signal peptide are capable of affecting cell viability. The results indicated a possible correlation between stability of the BRP signal peptide and cloacin DF13-release.
van der Wal
F J
FJ
Department of Microbiology, Biocentrum Amsterdam, The Netherlands.
Valent
Q A
QA
ten Hagen-Jongman
C M
CM
de Graaf
F K
FK
Oudega
B
B
Luirink
J
J
D000409:Alanine; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D007544:Isopropyl Thiogalactoside / Q000494:pharmacology; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011499:Protein Processing, Post-Translational; D021382:Protein Sorting Signals / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000378:metabolism
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins; C052368:cloacin DF13-encoded bacteriocin release protein, E coli; D007544:Isopropyl Thiogalactoside; D000409:Alanine