• Microbiology and Biotechnology Letters
• /
• v.21 no.2
• /
• pp.125-131
• /
• 1993

The s-type pyocin, one kind of bacteriocins, is a bactericidal substabce of protein nature produced by certain Pseudomonas aeruginosa and is active against some other strains of the same or closely related species. Among many Pseudomonas aeruginosa strains collected from the patients at the Hospitals in Seoul and Taegu cities, some Pseudomonas aeruginosa pyocinogeny were determined by pyocin typing. As a result, Pseudomonas aeruginosa 90-2-2205 was selected as the S-type pyocin producing microorganism due to its highest antimicrobial and protease sensitivity.

• Microbiology and Biotechnology Letters
• /
• v.21 no.2
• /
• pp.132-138
• /
• 1993

The s-type pyocin was purified from the lysate of the mitomycin C-induced Pseudomonas aeruginosa 90-2-2205 cells by the other of ammonium sulfate precipitation, DEAE-Sephadex A-50 chromatography and Sephadex G-200 gel filtration. The purity was confirmed by the polyacry-lamide gel electrophoresis. The molecular weight of the purified pyocin was estimated 180, 000 by gel filtration. The pyocin was analyzed to be a complex of some polypeptides by the SDS-PAGE. The pyocin was stable by heat treatment and at pH 6-7.5 by adding 10-3% gelatin and 0.2M NaCl to the 10mM Tris-HCl buffer (pH7.5). Its killing action against the sensitive cells was assumably a single hit process.

• Korean Journal of Microbiology
• /
• v.25 no.1
• /
• pp.9-16
• /
• 1987

Three strains of bacteria utilizing salicylate, KU801(pKU5, pKU8), KU803(pKU6, pKU9), and KU806(pKU7, pKU10), were selected from the isolates and identified as Pseudomonas putida. By agarose gel electrophoresis, it was found that the strains had two plasmids each. All three strains were resistant to antibiotics such as ampicillin, tetracyclin, and chloramphenicol, and did not utilize other aromatic and aliphatic hydrocarbons examined except salicylate. The plasmids (pKU5, pKU6, and pKU7) of larger molecular weight were cured by treatment with mitomycin C and frequencies of curing were 0.4%, 1.67%, and 0.75%, respectively. Cured strains did not degrade salicylate and still had antibiotic resistances, which were identical with wild strains. The genes for salicylate degradation were proved to be enclded on thier plasmids. The molecular weights of pKU5 and pKU6 were estimated as 103.5Md, and that of pKU 7 as 101 Md. The new SAL plasmids, pKU5, pKU6, and pKU7 were transferred to P. putida and P. aeruginosa, but not to E. coli.