• Korean Journal of Microbiology
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• v.25 no.1
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• pp.1-8
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• 1987

An extracellular $\beta$-1, 3-glucanase from Pseudomonas stutzeri KF 13 was purified about 390 with 26% recovery. The purified enzyme revealed a single band by polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis. The enzyme was stable in a pH 6.0 to 9.0, and relatively thermostable. The optimal pH and temperature on the enzyme activity were found to be 5.8 and 45.deg.C, respectively. The activation energy was calculated to be 16,130 cal per mole. The Km value for laminarin was found to be 3ng per ml and the molecular weight was determined to be 28,000 by gel filtration and 26,000 daltons by SDS-acrylamide gel electrophoresis. The enzyme was inhibited by 1.0mM of $Hg^{2+}$, and strongly inhibited by 1.0mM of p-chloromercuribenzoic acid.

• Korean Journal of Microbiology
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• v.24 no.3
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• pp.295-301
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• 1986

The bacteria, which were capable of producing ${\beta}-1$, 3-glucanase inducibly by utilizing cell wall of Aspergillus fumigatus as a sole carbon source, were isolated from soil in the campus of Kyungpook National University. Among them, the strain which produced the enzyme excellently was selected and identified to be Pseudomonas stutzeri KF 13 by morphological, cultural and physiological examination. The optimal conditions for the enzyme production from Pseudomonas stutzeri KF 13 were investigated. the enzyme production was reached maximum state shen the broth cultured for 72hr at $30^{\circ}C$. And the enzyme showed the highest activity in the medium containing 3.5% cell wall as an inducer, 15% yeast autolysate as a nitrogen source and 0.05% $MnSO_4$ at pH 7.5.

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