Detection of methicillin resistance and slime factor production of Staphylococcus aureus in bovine mastitis

Abstract

This study aimed to detect methicillin resistant and slime producing Staphylococcus aureus in cases of bovine mastitis. A triplex PCR was optimized targetting 16S rRNA, nuc and mecA genes for detection of Staphylococcus species, S. aureus and methicillin resistance, respectively. Furthermore, for detection of slime producing strains, a PCR assay targetting icaA and icaD genes was performed. In this study, 59 strains were detected as S. aureus by both conventional tests and PCR, and 13 of them were found to be methicillin resistant and 4 (30.7%) were positive for mecA gene. Although 22 of 59 (37.2%) S. aureus isolates were slime-producing in Congo Red Agar, in PCR analysis only 15 were positive for both icaA and icaD genes. Sixteen and 38 out of 59 strains were positive for icaA and icaD gene, respectively. Only 2 of 59 strains were positive for both methicillin resistance and slime producing, phenotypically, suggesting lack of correlation between methicillin resistance and slime production in these isolates. In conclusion, the optimized triplex PCR in this study was useful for rapid and reliable detection of methicillin resistant S. aureus. Furthermore, only PCR targetting icaA and icaD may not sufficient to detect slime production and further studies targetting other ica genes should be conducted for accurate evaluation of slime production characters of S. aureus strains.

Characterization of virulence and antibiotic profile and agr typing of Staphylococcus aureus from milk of subclinical mastitis bovine in State of Rio de Janeiro

“…Genotypic characterization of S. aureus was performed by amplification of coagulase (coa) (Hookey et al, 1998) and species specific (nuc) (Ciftci et al, 2009) genes. The analysis of virulence factors comprised the detection of the following genes: icaA and icaD (Vasudevan et al, 2003) implicated in the production of slime; fnbA and fnbB that codifies fibronectin binding proteins; cap5 and cap8 related to the expression of capsule (El-Sayed et al, 2006) and the hemolysin genes hlA and hlB (Nilsson et al, 1999).…”

Caracterização fenotípica e molecular de isolados de Staphylococcus spp. obtidos de leite de ovelhas do Município de Chapecó-SC

“…No teste com o Agar Vermelho Congo, apenas 2,77% dos isolados foram considerados positivos, resultado inferior ao encontrado por Freeman, Falkiner e Keane (1989), que detectaram a produção de biofilme em 77,78% dos isolados de SCN estudados. Ciftci et al (2009), ao estudarem a produção de biofilme em Staphylococcus aureus de mastite bovina, encontraram 37,2% de isolados positivos para o teste do Agar Vermelho Congo, enquanto que para a PCR foi observado que 25,42% dos S. aureus possuíam os genes icaA e icaD. Freeman, Falkiner e Keane (1989), propuseram o Agar Vermelho Congo como método alternativo para detectar a produção de biofilme.…”

Detection of exopolysaccharide production and biofilm-related genes in Staphylococcus spp. isolated from a poultry processing plant

“…Several studies have reported a higher frequency of distribution of the ica genes and slime production in Staphylococcus isolates from milk (Melo et al, 2013;Rumi et al, 2013;Ciftci et al, 2009), meat, and contact surfaces in processing plants (Schlegelová et al, 2008), indicating the virulence potential of the strains evaluated.…”

“…Several studies have reported higher frequency of distribution of the ica genes in Staphylococcus isolates from foods (Melo et al, 2013;Rumi et al, 2013;Ciftci et al, 2009;Rode et al, 2007;Møretrø et al, 2003).…”