tailieunhanh - Báo cáo khoa học: "PCR-based detection of genes encoding virulence determinants in Staphylococcus aureus from bovine subclinical mastitis cases"

Tuyển tập các báo cáo nghiên cứu khoa học quốc tế về bệnh thú y đề tài: PCR-based detection of genes encoding virulence determinants in Staphylococcus aureus from bovine subclinical mastitis cases | J. Vet. Set. 2007 8 2 151-154 JOURNAL OF Veterinary Science PCR-based detection of genes encoding virulence determinants in Staphylococcus aureus from bovine subclinical mastitis cases Dewanand Rajaram Kalorey1 Yuvaraj Shanmugam1 Nitin Vasantrao Kurkure2 Kapil Kamalakarrao Chousalkar1 Sukhadeo Baliram Barbuddhe3 1 Department of Microbiology and 2Pathology Nagpur Veterinary College Maharashtra Animal and Fishery Sciences University Nagpur Maharashtra India 3ICAR Research Comp lex for Goa Old Goa India The present study was carried out to genotypically characterize Staphylococcus aureus S. aureus isolated from bovine mastitis cases. A total of 37 strains of A. aureus were isolated during processing of 552 milk samples from 140 cows. The A. aureus strains were characterized phenotypically and were farther characterized genotypically by polymerase chain reaction using oligonucleotide primers that amplified genes encoding coagulase coa clumping factor elfA thermonuclease nuc enterotoxin A entA and the gene segments encoding the immunoglobulin G binding region and the X region of protein A gene spa. All of the isolates yielded an amplicon with a size of approximately 1 042 bp of the elf A gene. The amplification of the polymorphic spa gene segment encoding the immunoglobulin G binding region was observed in 34 isolates and X-region binding was detected in 26 isolates. Amplification of the coa gene yielded three different products in 20 10 and 7 isolates. The amplification of the thermonuclease gene nuc was observed in 36 out of 37 isolates. All of the samples were negative for the entA gene. The phenotypic and genotypic findings of the present strategies might provide an understanding of the distribution of the prevalent A. aureus clones among bovine mastitis isolates and might aid in the development of steps to control A. aureus infections in dairy herds. Key words genotyping India Staphylococcus aureus sub-clinical mastitis Introduction Staphylococcus aureus S. aureus