• Korean Journal of Microbiology
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• v.30 no.3
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• pp.199-206
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• 1992

Six isolated strains degrading aniline were selected, identified and designated as pseudomonas putida K6, Pseudomonas acidovorans K82, Achromobacter gr. D. V. K24, Achromobacter xylosocidans K4, Moraxella sp. K21 and Moraxella sp. K22. All of them degraded 1000 ppm aniline completely within 30 to 36 hours. Most of these strains are resistant to antibiotics more than one, but Moraxella sp. has not any antibiotic marker tested. Most strains except for P. acidovorans K82 were shown to have resistance to the heavy metal ions such as Ni, Cu, Li, Ba, Co, etc. but not to Hg to which only P. putida K6 was resistant. M. sp. K21 was capable of degrading aniline to a maximum concentration of 2500 ppm without any repression. The incubation of the cell in limited pH ranges (4-8) had no great effect on aniline degradation. The addition of bactopeptone to the minimal media promoted the speed of aniline degradation, but the addition of glucose rather repressed the rate of aniline degradation. Through enzyme assay, A. gr. D. V. K 24 was shown to degrade aniline through artho-pathway and formed .betha.-ketoadipate as intermediate metabolite.

• Journal of Environmental Science International
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• v.3 no.3
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• pp.197-207
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• 1994

Microorganisms capable of utilizing 2,4,5-trichlorophenoxyacetic acid(2,4,5-T) as sole carbon source were isolated from soil by enrichment culture. Among these strains, EL-O7IP had the highest biodegradability of 2,4,5-7, and according to its morphological and physiological characteristics, it was identified as Pseudomonas sp. This strain was resistant to rifampicin, streptomycin, ampicillin, kanamycin and such metal ions as $Zn^{2+}$, $Cu^{2+}$ Various compounds of chlorinated phenol and substrate analogs were more easily utilized than 2,4,5-7, but biodegradation rate for each compound was different. The strain easily utilized the compounds of chlorinated substituents on phenol in the order of ortho-, para-, and meta- position. The biodegradability of this strain was very stable. Key words : 2,4,5- trichlorophenoxyacetic acid, Pseudomonas sp .

• Journal of Microbiology and Biotechnology
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• v.29 no.12
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• pp.1916-1924
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• 2019

Outbreaks of staphylococcal food poisoning (SFP) causing serious human diseases and economic losses have been reported globally. Furthermore, the spread of Staphylococcus aureus with increased resistance to multiple antimicrobial agents has become a major concern in the food industries and medicine. Here, we isolated an endolysin LysSAP8, as one of the peptidoglycan hydrolases, derived from the bacteriophage SAP8 infecting S. aureus. This endolysin was tagged with a 6×His at the C-terminal of the target protein and purified using affinity chromatography. LysSAP8 demonstrated lytic activity against a broad spectrum of bacteria, which included a majority of the staphylococcal strains tested in this study as well as the methicillin-resistant S. aureus (MRSA); however, no such activity was observed against other gram-positive or gram-negative bacteria. Additionally, LysSAP8 could maintain bactericidal activity until 0.1 nM working concentration and after heat treatment at 37℃ for 30 min. The ability of LysSAP8 to lyse cells under varying conditions of temperature (4-43℃), pH (3-9), and NaCl concentrations (0-1,000 mM), and divalent metal ions (Ca²⁺, Co²⁺, Cu²⁺, Mg²⁺, Mn²⁺, Hg²⁺, and Zn²⁺) was examined. At the optimized condition, LysSAP8 could disrupt approximately 3.46 log CFU/ml of the planktonic cells in their exponential phase of growth within 30 min. In this study, we have suggested that LysSAP8 could be a potent alternative as a biocontrol agent that can be used to combat MRSA.

• Korean Journal of Environmental Agriculture
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• v.11 no.1
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• pp.77-85
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• 1992

Of the cadmium-tolerant 162 bacterial strains isolated from soils, river waters or active sludges of waste-water disposal plants in the Gyeongnam province a strain C1, which showed considerably higher growth rate in the agar plate containing 2000 ppm than any other strains isolated, was identified as a Pseudomonas putida or its similar strain when analyzed by taxonomical characteristics. Optimum pH and temperature for the growth of the P, putida were 7.0 and $30^{\circ}C$, respectively. This strain was resistant to antibiotics(ampicillin, chloramphenicol and streptomycin), and heavy metals(lithium, cupper, lead and zinc). This strain utilized salicylate, naphthalene or xylene as a sole carbon source. The rate of cadmium accumulation in P. putida cell was enhanced at low concentration of Cd in the growth media. The maximum cadmium absorption by this strain grown in 1 and l0ppm of Cd was respectively 78% and 60% 24 hrs after culture, but in 100 ppm Cd, 40% 48 hrs after culture. Addition of a non-ionic surfactant Triton X-100(0.1%) to the medium enhanced the accumulation of cadmium in the P. putida up to approximately 37%.

• Journal of Environmental Health Sciences
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• v.37 no.4
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• pp.279-288
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• 2011

Objectives: This study investigated the levels and components of floor-settled dust in two elementary schools located at different sites (one near the Shihwa industrial complex and the other in a rural area) in order to evaluate the amounts of trace metal elements (As, Cd, Co, Cr, Cu, Ni, Pb and Zn) and microorganisms. Methods: Over twenty settled-dust samples were collected from the two elementary schools. Trace metal elements were extracted from the dust using hydrochloric acid and nitric acid, and the amounts were measured by ICP-OES. Microbiological analysis was performed by bacterial culturing using R2A medium and denaturing gradient gel electrophoresis (DGGE). Results: The results showed that the amounts of three metal elements (Cr, Pb, and Zn) were significantly different between the schools (${\alpha}$=0.05, p<0.04). In addition, microbial communities in each school were highly correlated with one another. Among the identified microorganisms, a number of potentially opportunistic microorganisms, including antibiotic-resistant bacteria such as Acinetobacter baumannii, were found. Conclusions: This study will provide preliminary data for assessing levels and types of chemical and microbiological agents in elementary schools and for further evaluating human health risks associated with the agents.