Przeciwbakteryjna aktywność protegryny-1 w stosunku do szczepów Staphylococcus pseudintermedius i Staphylococcus aureus pochodzących od zwierząt
[Antibacterial activity of protegrin-1 against Staphylococcus pseudintermedius and Staphylococcus aureus strains isolated from animals]

STRESZCZENIE

Szerząca się obecnie lekooporność gronkowców wywołujących infekcje zarówno u ludzi jak i zwierząt oraz możliwość ich transmisji stanowi światowy problem zdrowia publicznego. Trwają poszukiwania alternatywnych związków przeciwbakteryjnych, dobrym kandydatem wydają się być peptydy przeciwdrobnoustrojowe. Niniejsza praca miała na celu określenie aktywności przeciwbakteryjnej protegryny-1 wobec szczepów Staphylococcus pseudintermedius i Staphylococcus aureus pochodzących od zwierząt.

ABSTRACT

Introduction: The bacterial resistance to the most clinically available antimicrobial agents has increased significantly. Frequent use of antibiotics in treatment and prevention of staphylococcal infections results in emerging antibiotic resistance of human and animal isolates. The resistance threat demands an increased effort to search for alternative chemotherapeutic compounds with new mechanisms of action. A good candidate for alternatice to classical antibiotics seems to be naturally produced in all living organisms antimicrobial peptides (AMPs). The aim of the study was to analyze the in vitro activity of antimicrobial peptide protegrin-1 (PG-1) against S. aureus and S. pseudintermedius strains isolated from animal infections.

Materials and methods: The susceptibility of staphylococci strains to antibiotics was tested with the disk diffusion method in line with the EUCAST standards. Protegrin-1 was synthesized by Fmoc method, purified by SPE (Solid-Phase Extraction) or HPLC (High- Performance Liquid Chromatography) and analyzed by mass spectrometry MALDI-TOF (Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry). The activity of protegrin-1 was examined using the broth dilution method in line with the Clinical Laboratory Standards Insitute (CLSI) guidelines to designated MIC (Minimal inhibitory concentrations) and MBC (Minimal Bactericidal Concentration) values.

Results: Investigated S. aureus and S. pseudintermedius isolates were susceptible to protegrin- 1. MIC50 and MIC90 for S. pseudintermedius equaled respectively 2 μg/mL and 4 μg/ mL, while for S. aureus equaled 8 μg/mL and 32 μg/mL. All investigated strains S. aureus had MBC values the same as MICs. Whereas S. pseudintermedius strains had MBC values

higher by one rank of MICs measure.

Conclusions: Investigated animal staphylococci strains were susceptible to natural antimicrobial peptide protegrin-1. The activity of PG-1 was irrespective of staphylococcal antibiotic resistance.

Key words: protegrin-1, PG-1, antimicrobial peptides, AMPs, Staphylococcus pseudintermedius, Staphylococcus aureus