AUTHOR=Fernández-Fernández Rosa , Lozano Carmen , Eguizábal Paula , Ruiz-Ripa Laura , Martínez-Álvarez Sandra , Abdullahi Idris Nasir , Zarazaga Myriam , Torres Carmen 

TITLE=Bacteriocin-Like Inhibitory Substances in Staphylococci of Different Origins and Species With Activity Against Relevant Pathogens

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.870510

DOI=10.3389/fmicb.2022.870510

ISSN=1664-302X

ABSTRACT=Bacteriocins are antimicrobial peptides with relevance in the modulation of human and animal microbiota that have gain interest in biomedical and biotechnological applications. In this study, the production of bacteriocin-like inhibitory substances  (BLIS) was tested among a collection of 890 staphylococci of different origins (humans, animals, food and the environment) and species, both coagulase-positive- (CoPS, 238 isolates of 3 species) and coagulase-negative-staphylococci (CoNS, 652 isolates of 26 species). Sixty of the 890 staphylococci (6.7%) showed antimicrobial activity by the spot-on-lawn method against at least one of the 25 indicator bacteria tested. BLIS producer (BLIS+) isolates were detected in 8.8% of CoPS and in 6.0% of CoNS. The species with the highest percentages of BLIS+ isolates were: S. chromogenes (38.5%), S. pseudintermedius (26.7%) and S. warneri (23.1%). The production of BLIS was more frequently detected among isolates of pets, wild animals and food. Moreover, 13 BLIS+ isolates showed high or medium antimicrobial activity and 7 of these isolates (of species S. aureus, S. pseudintermedius, S. sciuri, and S hominis) demonstrated antimicrobial activity against more than 70% of the indicator bacteria tested. The genetic characterization (by PCR and sequencing) of the 60 BLIS+ isolates revealed the detection of: a) 11 CoNS and CoPS isolates  carrying putative lantibiotic-like genes; b) 2 S. pseudintermedius isolates harbouring the genes of BacSp222-bacteriocin; and c) 2 S. chromogenes isolates which presented the gene of a putative cyclic bacteriocin (uberolysin-like), being the first report in this CoNS species. Antimicrobial susceptibility testing was performed in BLIS+ isolates and one-third of the CoNS isolates showed susceptibility to all antibiotics tested, that also lacked the virulence genes studied. These BLIS+ CoNS could be considered as good candidates for further characterization studies.