Growth conditions affect biofilms of Staphylococcus aureus producing mastitis: Contribution of MALDI-TOF-MS to strain characterization

CÁCERES, MARÍA EMILIA; LEDESMA, MARTÍN MANUEL; LOMBARTE SERRAT, ANDREA; VAY, CARLOS; SORDELLI, DANIEL OSCAR; GIACOMODONATO, MÓNICA NANCY; BUZZOLA, FERNANDA ROXANA

Current Research in Microbial Sciences

Elsevier

Año: 2021 vol. 2

2666-5174

Bovine mastitis is a disease of dairy cattle prevalent throughout the world that causes alterations in the quality and composition of milk, compromising technological performance. Staphylococcus aureus is one of the most important pathogens that produce clinical, subclinical, and chronic mastitis. Biofilms are considered a virulence factor necessary for the survival of S. aureus in the mammary gland. Its zoonotic potential is important not only for the dairy industry sector but also for public health. This study aimed to evaluate the effect of different growing culture conditions on the biofilm formation of S. aureus isolated from mastitis and to test the MALDITOF- MS?s ability to discriminate among different biofilm formation levels. Fluids commonly found in the dairy environment were incorporated to approach the pathogen?s behavior in natural surroundings. PIA production was also evaluated. All strains were able to form high biofilms in TSB, TSBg, and milk. Milk changed the behavior of some strains which formed more biofilms in this medium than in TSBg. The free iron medium CTSBg and milk whey inhibited the biofilm formation of the most strains. MALDI-TOF-MS performance was an excellent tool to discriminate between high, moderate, and low biofilm producers strains of S. aureus in each media, confirming the results of crystal violet assay. PIA production was variable among the strains and showed a media-dependent behavior. Our data highlights the importance of considering the growing conditions that mimic the natural ones to the study of biofilm formation in vitro.Current Research in Microbial Sciences is a gold open access (OA) journal, which means articles are permanently and freely available. It is a companion to the highly regarded review journal Current Opinion in Microbiology (COMICR; 2019 Journal Impact Factor 8.134, CiteScore 14.0) and is part of the Current Opinion and Research (CO+RE) suite of journals. All CO+RE journals leverage the Current Opinion legacy-of editorial excellence, high-impact, and global reach-to ensure they are a widely read resource that is integral to scientists´ workflow