Antimicrobial Activity of Corynebacterium amycolatum ICIS 53 and Corynebacterium amycolatum ICIS 82 Against Urogenital Isolates of Multidrug-Resistant Staphylococcus aureus.

Intermicrobial interactions play a key role in the regulation of microbial populations and the colonization of various ecological niches. In the present study, we assessed the effect of cell-free supernatants (CFSs) from the vaginal isolates Corynebacterium amycolatum ICIS 53 and Corynebacterium amycolatum ICIS 82 on urogenital test strain biofilm formation of Staphylococcus aureus. Our studies showed that the CFSs of both C. amycolatum strains significantly reduced biofilm formation and disrupted preformed S. aureus biofilms. Pretreatment with C. amycolatum ICIS 53 or C. amycolatum ICIS 82 CFSs decreased the cell surface hydrophobicity and exopolysaccharide production of all the test S. aureus isolates. The scanning electron microscopy (SEM) results showed that the CFSs of corynebacteria caused the S. aureus biofilms to be small clusters scattered across the surface, there were no fibres or adhesions between cells, and the cell membrane was not damaged. Treatment of preformed biofilms with CFSs from both C. amycolatum strains resulted in a flat, scattered, and unstructured architecture. The S. aureus cell membrane was damaged. GC‒MS analysis of the CFS of C. amycolatum ICIS 53 revealed the presence of 22 chemical compounds, including long-chain fatty alcohols, esters, fatty acids and heterocyclic pyrrolizines and pyrazoles, that, according to the literature, exhibit a wide range of biological activities. The results of the present work provide insight for the study of Corynebacterium microorganisms as a source of multifunctional bioactive compounds, which may find promising applications in the medical, biotechnological and pharmaceutical industries.