Affiliations: 1 Department of Infectious Diseases, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
2 Department of Bioinformatics and Computational Biology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
Keywords:
bacterial secretion, signal peptidase, bacterial resistance.
Corresponding Author(s):
Wouter Hazenbos, whazenbos@yahoo.com
Conflict of interest statement:
The authors have no conflict of interest.
Please cite this article as:
Wouter L.W. Hazenbos, Elizabeth Skippington and Man-Wah Tan (2017). Staphylococcus aureus type I signal peptidase: essential or not essential, that’s the question. Microbial Cell 4(4): 108-111.
© 2017 Hazenbos et al. This is an open-access article released under the terms of the Creative Commons Attribution (CC BY) license, which allows the unrestricted use, distribution, and reproduction in any medium, provided the original author and source are acknowledged.
Staphylococcus aureus type I signal peptidase: essential or not essential, that’s the question
Authors:Wouter L.W. Hazenbos1, Elizabeth Skippington2 and Man-Wah Tan1
doi: 10.15698/mic2017.04.566
Volume 4, pp. 108 to 111, published 17/03/2017.
1 Department of Infectious Diseases, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
2 Department of Bioinformatics and Computational Biology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
Keywords:
bacterial secretion, signal peptidase, bacterial resistance.
Corresponding Author(s):
Conflict of interest statement:
The authors have no conflict of interest.
Please cite this article as:
Wouter L.W. Hazenbos, Elizabeth Skippington and Man-Wah Tan (2017). Staphylococcus aureus type I signal peptidase: essential or not essential, that’s the question. Microbial Cell 4(4): 108-111.
© 2017 Hazenbos et al. This is an open-access article released under the terms of the Creative Commons Attribution (CC BY) license, which allows the unrestricted use, distribution, and reproduction in any medium, provided the original author and source are acknowledged.
Abstract:
Secretion of proteins into the extracellular environment is crucial for the normal physiology and virulence of pathogenic bacteria. Type I signal peptidase (SPase I) mediates the final step of bacterial secretion, by cleaving proteins at their signal peptide once they are translocated by the Sec or twin-arginine (Tat) translocon. SPase I has long been thought to be essential for viability in multiple bacterial pathogens. Challenging this view, we and others have recently created Staphylococcus aureus bacteria lacking the SPase I SpsB that are viable and able to grow in vitro when over-expressing a native gene cassette encoding for a putative ABC transporter. This transporter apparently compensates for SpsB’s essential function by mediating alternative cleavage of a subset of proteins at a site distinct from the SpsB-cleavage site, leading to SpsB-independent secretion. This alternative secretion system also drives the main mechanism of resistance to an arylomycin-derived SpsB inhibitor, by means of mutations in a putative transcriptional repressor (cro/cI) causing over-expression of the ABC transporter. These findings raise multiple interesting biological questions. Unraveling the mechanism of SpsB-independent secretion may provide an interesting twist to the paradigm of bacterial secretion.