Evaluation of the type I signal peptidase as antibacterial target for biofilm-associated infections of Staphylococcus epidermidis.
The development of antibacterial resistance is inevitable and is a major concern in hospitals and communities. Moreover, biofilm-grown bacteria are less sensitive to antimicrobial treatment. In this respect, the Gram-positive Staphylococcus epidermidis is an important source of nosocomial biofilm-associated infections. In the search for new antibacterial therapies, the type I signal peptidase (SPase I) serves as a potential target for development of antibacterials with a novel mode of action. This enzyme cleaves off the signal peptide from secreted proteins, making it essential for protein secretion, and hence for bacterial cell viability. S. epidermidis encodes three putative SPases I (denoted Sip1, Sip2 and Sip3), of which Sip1 lacks the catalytic lysine. In this report, we investigated the active S. epidermidis SPases I in more detail. Sip2 and Sip3 were found to complement a temperature-sensitive Escherichia coli lepB mutant, demonstrating their in vivo functional activity. In vitro functional activity of purified Sip2 and Sip3 proteins and inhibition of their activity by the SPase I inhibitor arylomycin A(2) were further illustrated using a fluorescence resonance energy transfer (FRET)-based assay. Furthermore, we demonstrated that SPase I not only is an attractive target for development of novel antibacterials against free-living bacteria, but also is a feasible target for biofilm-associated infections.
Bockstael
Katrijn
K
Laboratory of Medicinal Chemistry, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium.
Geukens
Nick
N
Laboratory of Bacteriology, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium.
Van Mellaert
Lieve
L
Laboratory of Bacteriology, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium.
Herdewijn
Piet
P
Laboratory of Medicinal Chemistry, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium.
Anné
Jozef
J
Laboratory of Bacteriology, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium.
Van Aerschot
Arthur
A
Laboratory of Medicinal Chemistry, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium.
D018441:Biofilms / Q000187:drug effects*; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004926:Escherichia coli / Q000235:genetics; D031541:Fluorescence Resonance Energy Transfer; D005816:Genetic Complementation Test; D008565:Membrane Proteins / Q000378:metabolism*; D008826:Microbial Sensitivity Tests; D009842:Oligopeptides / Q000494:pharmacology*; D012697:Serine Endopeptidases / Q000378:metabolism*; D013212:Staphylococcus epidermidis / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics
D004269:DNA, Bacterial; D004791:Enzyme Inhibitors; D008565:Membrane Proteins; D009842:Oligopeptides; C488532:arylomycin A2; D012697:Serine Endopeptidases; C026515:type I signal peptidase