Production, purification and some properties of Bac201, a bacteriocin-like inhibitory substance produced by Staphylococcus aureus AB201

Abstract

Staphylococcus aureus AB201, a clinical isolate from wound pus, produced a bacteriocin-like inhibitory substance termed as Bac201, that was inhibitory to Streptococcus agalactiae, Enterococcus faecalis, Acinetobacter calcoaceticus, Neisseria meningitidis and a number of staphylococcal species. It was purified to homogeneity by ammonium sulfate precipitation, gel filtration (BioSil-SEC-125), and reversed-phase high performance liquid chromatography (Vydac C4). The native Bac201 was sized at approximately 170-kDa as determined by GF HPLC. Fraction-I (native Bac201), having antibacterial activity was also examined by transmission electron microscopy and appeared as globular structure showing resemblance with phage-like objects. The purification of Bac201 resulted in 466-fold increase in specific activity and recovery of 0.94% of total antibacterial activity. The purified Bac201 migrated as single band on SDS-PAGE with an estimated molecular mass of about 41-kDa. Bac201 was sensitive to proteolytic enzymes, resistant to heat and organic solvents, and active over a wide range of pH (2.5-10). The amino acid composition revealed a general resemblance with other reported high molecular mass bacteriocins and predominance of glycine (39%), proline (13%) and alanine (8%) residues. Further results showed that Bac201 has a bactericidal effect on sensitive cells which is not produced by either cell lysis or apparent loss of membrane permeability.

The anti- Leishmaniasis activity of Purified Bacteriocin Staphylococcin and Pyocin Isolated from Staphylococcus aureus and Pseudomonas aeruginosa

“…The precipitate was recovered by centrifugation at 15,000 rpm for 50 min at 4°C and solubilized in 200 mL of 50mM sodium phosphate buffer pH 7.0. The resulting pellet and designated as crude preparation [15].…”

“…Crude bacteriocin was heated to denaturant any proteases and heat-sensitive proteins. Ammoinum sulphat extraction completely showed recovery of Staphylococcin and Pyocin activity, extraction by ammonium sulphate 70% show inhibition zone diameter reached (17,15) mm respectively by using as indicator strain of E.coli Figure- The crude ammonium sulfate precipitate was further subjected to conventional gel filtration chromatography on Sepahdex-G75 column eluted with 50 mM sodium phosphate buffer, pH 7.0. This separation profile resulted in two major and well separated peaks designated as peak I bacterocin (Fig.…”

A novel Alcaligenes faecalis antibacterial-producing strain isolated from a Moroccan tannery waste

“…To check the thermal stability, acetyl ethyl extract of the bacterial cells was exposed to 121°C (20 min), 100°C (15 min), 80°C (30 min), 37°C (3 h) and 4°C (six months) and subsequently the activity was checked as previously described (Iqbal et al, 2001;Thangam and Rajkumar, 2006).…”

Aerococcus sp. with an antimycobacterial effect

“…To check the thermal stability, strain acetyl ethyl and ammonium sulfate extracts were exposed to 80°C (30 min), 100°C (15 min) and 4°C (1 month), and the activity was checked by well-diffusion assay which was done three times and the average of the inhibition zone diameter was calculated (Iqbal et al, 2001).…”