Identification of staphylococcal cassette chromosome mec in Staphylococcus aureus and non-aureus staphylococci from dairy cattle in Belgium: Comparison of multiplex PCR and whole genome sequencing. (February 2023)

• Record Type: Journal Article
• Authors: Tchamba, Cyrille Ngassam; Touzain, Fabrice; Fergestad, Marte; De Visscher, Anneleen; L'Abee-Lund, Trine; De Vliegher, Sarne; Wasteson, Yngvild; Blanchard, Yannick; Argudín, Maria A.; Mainil, Jacques; Thiry, Damien
• Is Part Of: Research in veterinary science. Volume 155(2023)
• Page Start: 150
• Page End: 155
• Publication Date: 2023-02
• Subjects: Dairy cattle -- Methicillin resistance -- Staphylococcal cassette chromosome SCCmec -- Multiplex PCR -- Whole genome sequencing; Veterinary medicine -- Periodicals; Veterinary Medicine -- Periodicals; Médecine vétérinaire -- Périodiques; Médecine vétérinaire -- Recherche -- Périodiques; Diergeneeskunde; 636.089
• DOI: 10.1016/j.rvsc.2023.01.011
• Languages: English
• ISSNs: 0034-5288

Abstract

Abstract: The present study compared multiplex PCR (mPCR) and Whole Genome Sequencing (WGS) using the SCC mec Finder database to identify the Staphylococcal Cassette Chromosome (SCC) mec in five Staphylococcus aureus (SA) and nine non- aureus staphylococci (NAS) isolated from dairy cattle. mPCR identified an SCC mec IV in four SA and one NAS, but could not differentiate between SCC mec II and IV in the fifth SA, that all harbored the mecA gene and were phenotypically resistant to cefoxitin. SCC mec Finder confirmed the presence of an SCC mec IVc(2B) in four SA and of the SCC mec IVa(2B) in the fifth SA and the one NAS. Both methods also detected one untypeable SCC mec in another cefoxitin-resistant NAS harboring the mecA gene and a pseudo SCC mec in one cefoxitin-sensitive NAS harboring one mecC -related gene. No SCC mec elements were identified either in one cefoxitin-sensitive NAS harboring the mecA2 gene, or in five NAS (one resistant and four sensitive to cefoxitin) harboring the mecA1 gene. SCC mec Finder could even not identify the presence of any mecA1 gene in these five NAS, whose presence was nevertheless confirmed by ResFinder. The conclusions of this study are: (i) mPCR and WGS sequencing using SCC mec Finder are complementary methodologies to identify SCC mec ; (ii) SCC mec Finder and ResFinder to a lesser extent cannot identify all mec gene allotypes; (iii) a specific classification of the SCC mec in NAS would be epidemiologically helpful; (iv) presence of a mecA gene and a complete SCC mec is linked to cefoxitin resistance, whereas presence of other mec genes and of pseudo or no SCC mec is not. Highlights: WGS is more accurate than multiplex PCR to identify SCC mec (sub-)types. ResFinder is more accurate than SCC mec Finder to identify the mec gene allotypes. Non- aureus staphylococci can harbor untypeable, incomplete or no SCC mec . mec genes and SCC mec are more homogeneous between isolates of the same, than of different Staphylococcus species. Cefoxitin resistance is linked to mecA gene and complete SCC mec, but not to other mec genes and pseudo-SCCmec or no SCC mec .