• Korean Journal of Veterinary Service
• /
• v.44 no.3
• /
• pp.133-140
• /
• 2021

This study was aimed to investigate the prevalence and antimicrobial resistance of Pseudomonas spp. isolated from bovine mastitis milk samples. A total of 50 (4.9%) Pseudomonas spp. was isolated from 1,023 samples, those collected between 2018 and 2021, derived from 110 dairy farms. The prevalence of the identified species of Pseudomonas isolates was as follows; P. aeruginosa (70.0%), P. fluorescens (14.0%), P. putida (10.0%), P. fragi (4.0%), and P. chlororaphis (2.0%). Most of somatic cell counts in the quarter milk carrying Pseudomonas spp. were less than 3,000,000 cell/ml (90.0%). The isolates of Pseudomonas spp. showed high susceptibility to cefepime (98.0%), ciprofloxacin (98.0%), ceftazidime (96.0%), and colistin (96.0%). The rate of antibiotic resistance in the isolates was highest to ceftiofur (92.0%), followed by the resistance rate to chloramphenicol (86.0%) and trimethoprim/sulphamethoxazole (80.0%). In addition, there is a remarkable difference in antimicrobial resistance pattern among Pseudomonas species. P. aeruginosa and P. putida showed a similar resistance pattern, whereas P. fluorescens showed exceptionally lower resistance to trimethoprim/sulphamethoxazole and chloramphenicol than that of the other species. This study showed that prevalence of Pseudomonas spp. other than P. aeruginosa were 30.0% in bovine mastitis milk, and the occurrence rate of antibiotic resistance were similar or higher level, compared with the previous reports on the mastitisderived Pseudomonas spp. isolated in Korea.

• Journal of Microbiology
• /
• v.35 no.4
• /
• pp.290-294
• /
• 1997

4-Chlorobiphenyl-degrading Pseudomonas sp. DJ-12 was able to degrade 4-chlorobenzoate(4CBA), 4-iodobenzoate, and 4-bromobenzoate completely under aerobic conditions. During. the degradation of 4CBA by Pseudomonas sp. DJ-12, chloride ions were released by dechlorination and 4-hydroxybenzoate was produced as an intermediate metabolite. The NotI-KNA fragments of pKC157 containing dechlorination genes hybridized with the gene encoding 4CBA:CoA dehalogenase of Pseudomonas sp. CBS3 which is responsible for the hydrolytic dechlorination of 4CBA. These results imply that Pseudomonas sp. DJ-12 degrades 4CBA to 40hydroxybenzoate via dechlorination as the initial step of its degradativ pathway. The genes responsible for dechlorination of 4CBA were found to be blcated on the chromosomal DNA of Pseudomonas sp. DJ-12.

• 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.

• Journal of Life Science
• /
• v.9 no.6
• /
• pp.715-721
• /
• 1999

The biodegradative potentialities of a toluene-tolerant Pseudomonas sp. BCNU 154, isolated from waste water, were investigated. Among 16 aromatic substrates tested, cumene, cyclohexane, ethylbenzene, p-xylene, m-xyene, toluene and diphenylether were metabolized. Pseudomonas sp. BCNU 154 degraded aerobically toluene, ethylbenzene, p-xylene and cumene. With toluene competitive degradation occurred after 12 hours, but with p-xylene and cumene, and with ethylbenzene, 90 and 75% degradation occurred after 12 hours of incubation, respectively.

• Journal of Food Hygiene and Safety
• /
• v.11 no.3
• /
• pp.165-170
• /
• 1996

The biodegradation of high concentration of benzoate by enrichment culture with Pseudomonas sp. was investigated. During 50 days continuous culture, average of removal rate of benzoate and COD were 90% and 83%, respectively. And the enzymatic activity of catechol 2,3-dioxygenase was determined in the continuous culture but not Catechol 1,2-dioxygenase. On the other hand, Pseudomonas sp in the culture was investigated with SEM and the result was revealed that the cell shape was more demage according concentration of benzoate.

• Korean Journal of Microbiology
• /
• v.25 no.2
• /
• pp.87-93
• /
• 1987

The properties of the plasmid pKU41 isolated from Pseudomonas putkda KU190 have been investigated, pKU41 was defined as an R plasmid having a transmissible ampicillin and tetracycline resistance determinant, and could be classified as a plasmid belonging to IncP-1 group according to incompatibility grouping.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.31 no.6
• /
• pp.852-858
• /
• 1998

We have isolated a bacterial strain that tends to kill P. micans from the mixed culture of p. minns plus seawater filtrate (poresize, 0.8 $\mu$m) collected at Masan bay in July 1996, in which the mixed culture grown in the f/2 medium. According to the experimental results of the isolated bacterium such as fatty acids analysis, morphological and biochemical characteristic tests, the strain was supposed to be a Pseudomonas and then it was named as Pseudomonas sp. LG-2. The killing effect of Pseudomonas sp. LG-2 against P. micans was proportionally increased with the concentrations of culture filtrate (pore size, 0.8 $\mu$m) is well as with the number of bacterium inoculated. In the mixed culture inoculated with $1.3\times10^6$ cells/ml of Pseudomonas sp. LG-2, the number of P. micans (2,000 cells/ml) was gradually decreased and then killed below 100 cells/ml within 7 days. In addition, the culture filtrate with $30\%$ of final concentration revealed a significant killing effect against P. micans around 3 days after culture. In the relationship between killing effects and growth stage of Pseudomonas sp. LG-2, the culture filtrate at lag phase has little effects on P. micans. In constant, the culture filtrate at mid-log phase showed the killing effect by decreasing P. micans to 112 in number within 5 days. In particular, the culture filtrate at stationary phase showed a significant killing effect against P. micans in which the majority of it was killed after 3 day culture. The species specificity of killing effects of Pseudomonas sp. LG-2 against 5 species of dinoflagellate was only found in P. micans and Scrippsiella trochoidea.

• Mycobiology
• /
• v.33 no.1
• /
• pp.35-40
• /
• 2005

Selected isolates of Pseudomonas fluorescens (Pf4-92 and PfRsC5) and P. aeruginosa (PaRsG18 and PaRsG27) were examined for growth promotion and induced systemic resistance against Fusarium wilt of chickpea. Significant increase in plant height was observed in Pseudomonas treated plants. However, plant growth was inhibited when isolates of Pseudomonas were used in combination with Fusarium oxysporum f. sp. ciceri (FocRs1). It was also observed that the Pseudomonas spp. was colonized in root of chickpea and significantly suppressed the disease in greenhouse condition. Rock wool bioassay technique was used to study the effect of iron availability on the induction of systemic resistance to Fusarium wilt of chickpea mediated by the Pseudomonas spp. All the isolates of Pseudomonas spp. showed greater disease control in the induced systemic resistance (ISR) bioassay when iron availability in the nutrient solution was low. High performance liquid chromatography (HPLC) analysis indicated that an the bacterial isolates produced more salicylic acid (SA) at low iron ($10\;{\mu}M$ EDDHA) than high iron availability ($10\;{\mu}Fe^{3+}$ EDDHA). Except PaRsG27, all the three isolates produced more pseudobactin at low iron than high iron availability.

• KSBB Journal
• /
• v.14 no.5
• /
• pp.616-620
• /
• 1999

Ten denitrifying bacteria, which were identified as Pseudomonas sp., were isolated from Winogradsky columns. The most effective denitrifying bacterium was named as Pseudomonas CW4, which was cultivated at anoxic condition. The optimal growth temperature and pH were 3$0^{\circ}C$ and 6-8, respectively. The effect of carbon concentration and agitator speed on the rate of denitrification were very low. 100% of NO$_3$-N was removed after 15 hrs when initial concentration of NO$_3$-N was 142.5 mg/L.

• Journal of Life Science
• /
• v.12 no.5
• /
• pp.561-565
• /
• 2002

Pseudomonas sp. EL-041 was previously isolated from phenol-acclimated activated sludge. This bacterium was capable of degrading phenol and cometabolizing trichloroethylene (TCE). In this study, we report the identification of trichloroethylene- degrading enzyme in Pseudomonas sp. EL-041 by the investigation of enzyme activity and DNA sequencing of specific phenol oxygenase gene. As the results of experiment, trichloroethylene-degrading enzyme in Pseudomonas sp. EL-041 was monooxygenase and suspected to phenol hydroxylase.