Expression of genes encoding resistance in Staphylococcus spp. isolated from bovine subclinical mastitis in Brazil

Author(s)

Zuniga, Eveline ^[1] ; Benites, Nilson Roberti ^[1] ; da Hora, Aline Santana ^[2] ; Mello, Priscila Luiza ^[3] ; Laes, Marco Antonio ^[1] ; Ribeiro de Oliveira, Lilian Abgail ^[1] ; Brandao, Paulo Eduardo ^[1] ; de Souza Silva, Sheila Oliveira ^[1] ; Taniwaki, Sueli Akemi ^[1] ; Melville, Priscilla Anne ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Vet Med & Zootech, Dept Prevent Vet Med & Anim Hlth, Av Prof Dr Orlando Marques de Paiva 87, BR-05508270 Sao Paulo - Brazil

^[2] Fed Univ Uberlandia UFU, Sch Vet Med, Dept Prevent Vet Med, Uberlandia, MG - Brazil

^[3] Univ Guarulhos, Guarulhos, SP - Brazil

• Document type: Journal article
• Source: JOURNAL OF INFECTION IN DEVELOPING COUNTRIES; v. 14, n. 7, p. 772-780, JUL 2020.
• Web of Science Citations: 0

Abstract

Introduction: Staphylococci are the most important agents associated with bovine mastitis. This study aimed at characterizing resistance factors to antimicrobials in Staphylococcus spp. isolated from the milk of cows with subclinical mastitis. Methodology: In vitro resistance of 243 Staphylococcus spp. isolates to antimicrobials commonly used in clinical practice was evaluated. The detection and expression of genes encoding resistance mecA (gene encoding penicillin binding protein 2a) mecALGA251 (mecA homologue), blaZ (gene encoding penicillin resistance), femA and femB (genes encoding essential factors-A and B-for the expression of methicillin resistance) and aacA-aphD (gene encoding for a bifunctional enzyme that confers resistance to gentamicin) using PCR and RT-PCR was investigated. Results: One or more genes encoding resistance to different antimicrobials were detected in 184 Staphylococcus spp. samples. The femA and femB genes were the most frequent. Regarding the variables' detection (N = number of strains) and expression (% of strains), the following results were obtained: blaZ (N = 40-82.5%), femA (N = 147-47.6%), aacAaphD (N = 30-43.3%), femB (N = 138-29.7%), mecA (N = 33-27.3%), mecALGA251 (N = 01-0.0%). There was a higher occurrence of phenotypic resistant strains for amoxicillin, ampicillin and penicillin in isolates positive for detection and/or expression of blaZ gene when compared with the other genes. Conclusions: The present study provides new information on genotypic traits of Staphylococcus isolates from bovine subclinical mastitis especially regarding the evaluation of expression of genes associated with antimicrobial resistance in Staphylococcus spp. using molecular tools. (AU)

• FAPESP's process: 15/14209-4 - Antimicrobial resistance of Staphylococcus spp. isolated from clinical and subclinical bovine mastitis: phenotypic analysis, gene expression and relationship with the presence of genes encoding adhesins and biofilm
• Grantee: Priscilla Anne Melville
• Support Opportunities: Regular Research Grants