Title

Characterization of a leukocidin identified in Staphylococcus pseudintermedius

Source Publication (e.g., journal title)

PLOS ONE

Authors

Mohamed A. Abouelkhair, University of Tennessee, Knoxville
David A. Bemis, University of Tennessee, Knoxville
Richard J. Giannone, Oak Ridge National Laboratory
Linda A. Frank, University of Tennessee, Knoxville
Stephen A. Kania, University of Tennessee, KnoxvilleFollow

Document Type

Article

Publication Date

9-27-2018

DOI

10.1371/journal.pone.0204450

Abstract

Bacterial infections from Staphylococcus pseudintermedius are the most common cause of skin infections (pyoderma) affecting dogs. Two component pore-forming leukocidins are a family of potent toxins secreted by staphylococci and consist of S (slow) and F (fast) components. They impair the innate immune system, the first line of defense against these pathogens. Seven different leukocidins have been characterized in Staphylococcus aureus, some of which are host and cell specific. Through genome sequencing and analysis of the S. pseudintermediussecretome using liquid chromatography mass spectrometry we identified two proteins, named “LukS-I” and “LukF-I”, encoded on a degenerate prophage contained in the genome of S. pseudintermedius isolates. Phylogenetic analysis of LukS-I components in comparison to the rest of the leukocidin family showed that LukS-I was most closely related to S. intermediusLukS-I, S. aureus LukE and LukP, whereas LukF-I was most similar to S. intermedius LukF-I S. aureus gamma hemolysin subunit B. The killing effect of recombinant S. pseudintermediusLukS-I and LukF-I on canine polymorphonuclear leukocytes was determined using a flow cytometry cell permeability assay. The cytotoxic effect occurred only when the two recombinant proteins were combined. Engineered mutant versions of the two-component pore-forming leukocidins, produced through amino acids substitutions at selected points, were not cytotoxic. Anti-Luk-I produced in dogs against attenuated proteins reduced the cytotoxic effect of native canine leukotoxin which highlights the importance of Luk-I as a promising component in a vaccine against canine S. pseudintermedius infections.

Comments

This article was published openly thanks to the University of Tennessee Open Publishing Support Fund.

Licensed under a Creative Commons Attribution 4.0 International license.

Recommended Citation

Abouelkhair MA, Bemis DA, Giannone RJ, Frank LA, Kania SA (2018) Characterization of a leukocidin identified in Staphylococcus pseudintermedius. PLoS ONE 13(9): e0204450. https://doi.org/10.1371/journal.pone.0204450

Submission Type

Publisher's Version