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Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have become a rising threat to public health. There is an urgent need for development of promising new therapeutic agents against drug resistant bacteria like S. aureus . This report discusses purification and characterization of proteins from Indian Russell’s viper snake venom. Novel 15-kDa proteins called “Viperatoxin” (VipTx-I and VipTx-II) were extracted from the whole venom and evaluated using in vitro antimicrobial experiments. The N-terminal amino acid sequence of “Viperatoxin” showed high sequence homology to daboiatoxin isolated from the same venom and also matched phospholipase A 2 (PLA 2 ) enzymes isolated from other snake venoms. In an in vitro plate assay, VipTx-II but not VipTx-I showed strong antimicrobial effects against S. aureus and Burkholderia pseudomallei (KHW & TES), Proteus vulgaris and P. mirabilis . The VipTx-II was further tested by a broth-dilution assay at 100–3.125 μg/ml concentrations. The most potent bactericidal effect was found at the lowest dilutions (MICs of 6.25 μg/ml) against B. pseudomallei , S. aureus and P. vulgaris (MICs of 12.25 μg/ml). Electron microscopic investigation revealed that the protein-induced bactericidal potency was closely associated with pore formation and membrane damage, even at the lowest concentrations (<20 μg/ml). The toxin caused a low level of cytotoxic effects as observed in human (THP-1) cells at higher concentrations. Molecular weight determinations of VipTx-II by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed one major, along with a few minor bands. The results indicate that VipTx-II plays a significant role in bactericidal and membrane damaging effects in vitro . Non-cytotoxic properties on human cells highlight it as a promising candidate for further evaluation of antimicrobial potential in vivo . [ABSTRACT FROM AUTHOR]

Abstract: In this study 540 burns and wound swabs were collected from cancer patients of some Egyptian hospitals. The single infection was detected from 210, and 70 cases among wounded and burned patients, while mixed infection was 30 and 45, respectively. We recovered where 60 isolates of Pseudomonas aeruginosa, 60 isolates of Staphylococcus aureus, 7 isolates of Staphylococcus epidermidis, 4 isolates of Streptococcus pyogenes, 25 isolates of Escherichia coli, 23 isolates of Klebsiella pneumoniae and 27 isolates of Proteus vulgaris from 355 burn and surgical wound infections . All bacterial isolates showed high resistance to the commonly used β-lactams (amoxycillin, cefaclor, ampicillin, vancomycin, amoxicillin/clavulonic), and low resistance to imepenim and ciprofloxacin. Plasmid analysis of six multidrug resistant and two susceptible bacterial isolates revealed the same plasmid pattern. This indicated that R-factor is not responsible for the resistance phenomenon among the isolated opportunistic bacteria. The effect of ultraviolet radiation on the isolated bacteria was studied. [Copyright &y& Elsevier]