Molecular characterisation of Staphylococcus aureus from some artisanal Brazilian dairies

Abstract

The clonal relationships and antimicrobial resistance of Staphylococcus aureus isolates from three fresh Minas cheese production lines were investigated. Putative S. aureus were confirmed by 16S rRNA gene sequencing and were characterised by multilocus sequence typing (MLST) and antimicrobial susceptibility. Overall, 33 out of 64 samples were contaminated with S. aureus (51.6%). The contamination rates of the dairies were 60.8%, 21% and 68.2%. Thirty representative isolates were selected to be typed by MLST and five sequence types (ST) were found (ST1, 97, 126, 3531), including the new ST 3816. The clonal complex 1 (CC1) was dominant. Resistance to commonly used antimicrobials was observed but only one strain was resistant to methicillin. This methicillin resistant S. aureus strain belonged to the CC126 that is commonly associated with mastitis in ruminants. The dissemination of zoonotic bacteria through the food chain is not a frequent event but represents a concern to public health.

Microbial contamination level and microbial diversity of occupational environment in commercial and traditional dairy plants

“…Both these strain, probably originated from the processed milk, are responsible for mastitis in cattle and are often present in raw milk [57,58]. Staphylococcus aureus has also been frequently isolated from cheese production lines [59]. According to Schlegelová et al [60] staphylococci are present quite often in dairies on technical equipment, and the results obtained in the current study confirmed this observation.…”

Phenotypic Characterization and Whole Genome Analysis of a Strong Biofilm-Forming Staphylococcus aureus Strain Associated With Subclinical Bovine Mastitis in Colombia

“…According to PubMLST database, ST126 was assigned to CC97, since this matches at four loci with ST97 (central ST of CC97). Our results contrast with most of the reports, that place ST126 into CC126 ( 32 – 34 , 36 ). These studies probably used other methodologies (e.g., eBURST—it is a single-linkage method) or database ( www.mlst.net —currently not available) to assign the clonal complex.…”

Methicillin-resistant Staphylococcus aureus in food and the prevalence in Brazil: a review

“…Researches in different regions have been showing the incidence of MRSA in food and foodproducing animals, with an emphasis on milk and dairy products and meat and meat products. Furthermore, the importance of researches conducted with samples of food processing environments and food handlers should also be highlighted [65,89,90]. Next, studies shall be presented to demonstrate the incidence of S. aureus and specifically MRSA in Brazilian territory.…”

“…Alves et al [90] collected 64 samples from three dairy products from Minas Frescal artisanal cheese production located in the Midwest region of Goiás, Brazil. These samples include processing environments, raw materials, and final product.…”