Identification and Purification of Quorum Sensing Peptides Causing Apoptosis in Staphylococcus Aureus as New Treatment Antibiotics

Due to the increasing in antibiotic resistance in bacteria, especially the infections which their treatment is very difficult, there is a need for producing new drugs. The aim of this study was identification and purification of quorum sensing peptides causing apoptosis in Staphylococcus aureus as new treatment antibiotics.
The supernatant from Staphylococcus aureus, Enterococcus faecalis, and Enterococcus faecium were collected after centrifugation. Then, the supernatant was isolated from the specimens that had the greatest effect on the growth of bacteria. Liquid chromatography was used to purify it. In next step, for detection of protein concentration, Bradford test and for confirmation, two dimensional electrophoresis were used. Finally, to determine the antimicrobial activity of purified peptides, minimum inhibitory concentration (MIC) and minimum inhibitory concentration (MBC) of peptides were investigated.
Findings: The obtained effective ingredient was a polypeptide that was effective against multi-drug resistant bacteria. The results of MIC for methicillin-resistant Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella paratyphi A and B, Klebsiella oxytoka, Acinetobacter Bumanni, and Shigella dysenteria were 3.2, 7.0, 5.0, 5.0, 3.0, 6.0, 1.0, and 7.0 µg/ml, respectively.
The polypeptide derived from this study showed a vast antimicrobial property against gram-positive and gram-negative bacteria.