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. 2019 Nov 20;9(1):17176.
doi: 10.1038/s41598-019-53926-4.

Short tryptophan- and arginine-rich peptide shows efficacy against clinical methicillin-resistant Staphylococcus aureus strains isolated from skin and soft tissue infections

Mihaela Bacalum  1 , Elena-Carmina Dragulescu  2 , George Necula  3 , Irina Codita  2   4 , Mihai Radu  5
Affiliations

Short tryptophan- and arginine-rich peptide shows efficacy against clinical methicillin-resistant Staphylococcus aureus strains isolated from skin and soft tissue infections

Mihaela Bacalum et al. Sci Rep. .

Abstract

In recent years methicillin-resistant Staphylococcus aureus has posed a challenge in treating skin and soft tissue infections. Finding new antimicrobial agents has therefore become imperative. We evaluated the in vitro antimicrobial activity of a synthetic peptide, P6, against multidrug resistant clinical strains of Staphylococcus aureus isolated from skin and soft tissue infections. The P6 antimicrobial effect was evaluated in vitro by determining MIC/MBC, the ratio of live/dead cells and the effects induced at membrane level. The therapeutic efficiency was determined against human skin cells. P6 inhibited growth for all strains between 8 and 16 mg/L and killed all bacterial strains at 16 mg/L. The therapeutic potential was found to be 30 and 15 in the presence of BSA. We showed that P6 localizes at membrane level, where it acts slowly, by depolarizing it and affecting its integrity. P6 can be considered a good candidate for use as an antimicrobial agent in topical applications.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
In vitro toxicity of P6 on human skin fibroblasts.
Figure 2
Figure 2
Percentages (A) and ratios (B) of live and dead bacteria treated with different concentrations of P6.
Figure 3
Figure 3
Ratios red/green fluorescence of DiOC2(3) probe for bacteria treated with P6 for 2 h (A) and 24 h (B).
Figure 4
Figure 4
Localization of Rho-P6 in S. aureus: (A) S. aureus loaded with SYBR green, (B) S. aureus treated with 3x MIC Rho-P6 and (C) overlapping of the 2 images. Yellow arrows indicate the viable cells onto which the peptide did not attach, the white arrows indicate the dead cells with a high concentration of peptide attached and the blue arrows the cells that are still viable but to which the peptide started to attach to the membrane.
Figure 5
Figure 5
Morphological changes induced by P6 against A9 bacteria. Control (A), treated with MIC/2 (D) and with MIC (G) of P6: topography (A,D,G), cross section (B,E,H) and three dimensional (C,F,I) images.
See this image and copyright information in PMC

References

    1. Tong SY, Davis JS, Eichenberger E, Holland TL, Fowler VG., Jr. Staphylococcus aureus infections: epidemiology, pathophysiology, clinical manifestations, and management. Clin Microbiol Rev. 2015;28:603–661. doi: 10.1128/CMR.00134-14. - DOI - PMC - PubMed
    1. WHO. (WHO Press, 2014).
    1. Siegel, J. D. & Rhinehart, E. Marguerite Jackson, Linda Chiarello & Committee, t. H. I. C. P. A. (Mosby, Inc, United States, 2007).
    1. Drăgulescu, E. C., Buzea, M. & Codiță, I. Molecular Analysis of Community-Acquired Staphylococcus aureus strains isolated from Skin and Soft-Tissue Infections in Romania. Rom Biotechnol Lett Published online ahead of print, 10.26327/RBL2017.106 (2018).
    1. Graham, P. L. 3rd., Lin, S. X. & Larson, E. L. A U.S. population-based survey of Staphylococcus aureus colonization. Ann Intern Med144, 318–325 (2006). - PubMed

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