faecalis to S. inhibitors aureus 14 have been reported. Vancomycin-resistance gene acquisition
by S. aureus from Enterococcus faecium in the clinical environment has also been reported earlier. 15 In view of the increased spreading vancomycin-resistant vanA gene through conjugation, compelled us to explore chemicals that could be used as non-antibiotic adjuvants to control the spreading of resistance gene via conjugation from one gram-positive bacterial species to another species OSI-744 order of bacteria. There are no recent study regarding controlling of the spreading of vanA gene among the clinical isolates. The aim of the present study was to identify the vanA gene among clinical isolates of vancomycin-resistant S. aureus (VRSA). Thereafter, transfer of vanA gene through
conjugation from vanA positive VRSA to a vancomycin-sensitive S. aureus (VSSA) was evaluated. Next, we examined the effect of various concentrations of chemicals including ethylenediaminetetraacetic acid (disodium edetate), acid (EGTA) and boric acid on conjugation. All of the chemicals, such as ethylenediaminetetraacetic acid (disodium edetate), ethylene glycol tetraacetic acid (EGTA) and boric acid were procured from Himedia (Mumbai, India) and were reconstituted with water for injection. Working solutions were prepared using MH (Mueller Hinton, Himedia, Bombay, India) broth. A total of fourteen clinical isolates of VRSA were used in the present study of which four from patients suffering from surgical wounds and three from bacteremia and seven from patients suffering Palbociclib concentration with burns were recovered. All of the isolates were obtained from Vijayanagar Institute of Medical Sciences (VIMS), Bellary, India. Re-identification of these clinical isolates was done using standard microbiological and biochemical tests.16 and 17 The vanA positive isolate of VRSA served as donor and was grown overnight at 37 °C in Mueller-Hinton broth (MHB, Himedia, Mumbai, India) these and S. aureus (MTCC 737) obtained from
Institute of Microbial Technology, Chandigarh, India, served as recipient as well as negative control was also grown overnight in MHB. These bacterial suspensions were used as the inoculum at a concentration of 106 colony-forming units/milliliter (cfu/ml). E. faecium ATCC 51559, which contains vanA gene served as a positive control. All of the clinical isolates were processed for screening of vanA gene. DNA from all of the clinical isolates, recipient, transconjugants, positive and negative controls was isolated using following methods: five ml of each at concentration of 1010 cfu/ml was centrifuged at 5000 revolutions per minute (rpm) for 4 min at 25 degree celsius (°C) and pellet was washed once in phosphate buffer saline (0.05 Molar (M) pH 7.2). After addition of 0.2 ml ice-cold solution 1 [25 millimolar (mM) Tris(hydroxymethyl)aminomethane hydrochloride (Tris–HCl) pH 8.0, 10 mM ethylenediaminete-traacetic acid (EDTA) pH 8.0 and 50 mM glucose] and 0.