• Korean Journal of Microbiology
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• v.28 no.3
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• pp.236-242
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• 1990

To develop the new strains of microorganisms having the degradative ability for various aromatic hydrocarbons, the hybrid plasmid pKG2 having the 2,4-Dichlorophenoxyacetic acid(2,4-D) degradative genes, the hybrid plasmid pKG3 containg the naphthalene degradative genes and TOL plasmid were introduced into Pseudomonas putida KUD 12 and P. putida KUP 10 by transformation or conjugation which originally have the degradative ability of the synthetic surfactants and phthalate esters, respectively. From P. putida KUD12, the new strains of P. putida KUD101(pKG2), KUD102(pKG3), KUD103(TOL), and KUD202(pKG3, TOL) were obtained, and KUD106(pKG2), KUD107(pKG3), KUD108(TOL) were originated from the P.putida KUP10. The degradative abilities in P. putida KUD101, KUD102 and KUD107 were similar with those of the original strains. The P. putida KUD103, KUD106 and KUD202 had a little lower and P. putida KUD108 had a better degradative abilitie than those of the original ones. In the case of mixed cultures, the mixed culture of KUD107 and KUD108 had a better degradative abilities than those of the other mixed cultures.

• Korean Journal of Microbiology
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• v.25 no.4
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• pp.282-289
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• 1987

The characteristics of the plasmid pKU10 isolated from Pseudomonas putida KU816 were investigated and its restriction map was constructed. The pKU10 plasmid was a small R plasmid carrying genes for resistance to ampicillin, tetracyclin, and chloramphenicol, and cured by treatment with mitomycin C. The molecular size of pKU10 was estimated to be 9.4Kb. Pseudomonas strains and E. coli cells could be transformed for antibiotic resistance characters specified by pKU10 plasmid DNA. By incompatibility test with other plasmids, pKU10 is grouped into IncP-1. EcoRI, XhoI, SalI, BglII, and SmaI cleaved pKU10 once, while PstI cleaved at two sites, and HindIII cleaved at six sites. The restriction map was constructed by partial and complete digestion of the purified plasmid DNA with single, double, or triple restriction enzymes. Thus, pKU10 is expected to be used for a cloning vector in Pseudomonas cells.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1214-1220
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• 2005

Decreased porin-mediated outer membrane penetration of hydrophilic antibiotics is a common mechanism of antibiotic resistance in Gram-negative bacteria. This study was undertaken to determine whether a null mutation in Pseudomonas putida would suppress porin synthesis, and therefore reduce the susceptibility of the organism to streptomycin, norfloxacin, and tetracycline. Inverse PCR amplification and double-stranded DNA sequencing were used to identify chromosomal genes carrying TnphoA'-1 inserts. Genome database available was used to identify putative homologue genes, one of which encodes protein with homology to domains of the MutS of P. putida, suggesting a crucial role in the multidrug resistance. Increased resistance to streptomycin, norfloxacin, and tetracycline might be due to accumulation of compensatory mutations. Either no growth or slow growth was observed in P. putida KH1027 when grown in minimal medium containing gluconate, glucose, or citrate; however, it is not clear whether the growth patterns contributed to the multidrug resistance.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.859-862
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• 2004

An isolate of Pseudomonas putida has been found to aggressively colonize root tips and induce plant resistance to Fusarium wilt. However, P. putida mutants lacking Fe-superoxide dismutase (SOD) or both FeSOD and MnSOD activities are less competitive in root tip colonization. In the current study, the growth of an FeSOD mutant was found to be more sensitive than that of the wild-type or a MnSOD mutant to oxidative stress imposed by paraquat treatment and culturing with the soil fungus Talaromyces flavus, which generates reactive oxygen species. Also, the loss of culturability with an aging stationary-phase culture was greater for a double SOD mutant than an FeSOD mutant, while no reduction in culturability was observed with the wild-type and a MnSOD mutant under the same protracted stationary-phase conditions. Accordingly, it was concluded that FeSOD activity is the major form of SOD in P. putida and plays an essential role in survival under stress conditions when increased oxidative stress is encountered.

• Applied Biological Chemistry
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• v.39 no.6
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• pp.472-476
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• 1996

The major portions of two DNA fragments, one from degradative plasmid, pRA4000 from Pseudomonas putida NCIMB 9866, and the other from degradative plasmid, pRA500 from P. putida NCIMB 9869, which harbor the structural genes for the flavoprotein (pchF) and cytochrome (pchC) subunits of p-cresol methylhydroxylase (PCMH), have been sequenced. The DNA and deduced amino acid sequences for pchC and pchF have been published. In these fragments, a coding region (dhal) for an aldehyde dehydrogenase has been identified. It is proposed that this gene encodes for the aldehyde dehydrogenase which converts p-hydroxybenzyaldehyde to p-hydroxybenzoate. p-Hydroxybezealdehyde is the product of oxidation of p-cresol by PCMH. The fragment from P. putida 9869 also harbors the genes for the ${\alpha}$ (pcaG) and ${\beta}$ (pcaH) subunits of protocatechuate 3,4-dioxigenase. The fragment from 9866 does not have any portion of these genes in the corresponding region A possible open reading frame (ORF) between pchC and pchF is seen for both clones, and a second putative open reading frame (ORF') also exists in the 9866 clone. The gene organizations are dhal-pchC-ORF-pchF-pcaGH for the DNA fragment from 9869, and ORF-dhal-pchC-ORF-pchF for the DNA fragment from 9866.

• Journal of Life Science
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• v.20 no.8
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• pp.1214-1220
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• 2010

Imipenem-resistant bacteria were isolated from clinical specimens taken from hospitalized patients in Suncheon, Korea. Fifty-four isolates were phylogenetically analyzed based on 16S rRNA gene and gyrB gene sequence comparisons. Isolates were affiliated with Pseudomonas aeruginosa (30 strains; 55.6%), Acinetobacter baumannii (21; 38.9%), Enterobacter hormaechei (2) and Pseudomonas putida (2). Twenty-two isolates produced metallo-$\beta$-lactamase (MBL); 12 Acinetobacter baumannii strains, 7 Pseudomonas aeruginosa strains, 2 P. putida strains and 1 Enterobacter hormaechei strain. Antibiotic susceptibility of the isolates was determined using the disc diffusion method and Vitek system. Strains producing metallo-$\beta$-lactamase (type IMP & VIM) were more resistant to antibiotics ceftazidime, aztreonam, amikacin and gentamicin than to strains producing OXA and SHV type of $\beta$-lactamase.

• Research in Plant Disease
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• v.14 no.1
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• pp.32-36
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• 2008

Bacterial wilt caused by Ralstonia solanacearum has become a severe problem on tomato in Korea and no effective control measures are available yet. Pseudomonas species play key roles for the biocontrol of many plant diseases especially in soil. A rhizobacterial population of 150 Pseudomonas strains, isolated from the rhizosphere soil of various plants grown at different sites, was screened for 2,4-diacetylphloroglucinol producing gene (PhlD) by PCR. Two strains (P83 and P84) among them were found to be phlD positive. When the isolates were analysed by 16S rDNA (Sensu Stricto), all isolates yielded amplified products of 1,018bp. Of the 150 isolates of Pseudomonas spp., a bacterial strain P. putida P84 isolated from tomato rhizosphere showed to suppress a wide range of phytopathogenic bacteria in vitro. The best source of carbon for P84 strain were glucose, arabinose, inositol and melibiose. In greenhouse experiments, P84 strain suppressed the development of bacterial wilt in tomato with a control value of 60%.

• Journal of Microbiology and Biotechnology
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• v.7 no.5
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• pp.345-351
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• 1997

An aqueous/organic two-phase reaction system was applied to the production of catechol using immobilized resting cells of Pseudomonas putida CY 400. Water/ethyl ether system was used because of high partition coefficient of catechol and thus to reduce the product inhibition and degradation. Among the tested immobilization carriers, polyacrylamide gel gave the highest catechol productivity. The immobilization seemed to protect the cells against solvent toxicity. From the simulation of reaction conditions based on two-phase models, it was found that there was an optimum acetate concentration at fixed benzoate and cell concentrations for the catechol productivity. A lower phase volume ratio (lower fraction of organic phase) gave a higher productivity. However, the substrate conversion was low at low phase volume ratio.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.185-187
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• 1998

Pseudomonas putida KCTC 2401 degrades 1,1, 2-trichloroethylene (TCE) using phenol as a cosubstrate. The initial TCE degradation rate decreased with the initial TCE concentration up to 20mg/l of TCE at $30^{\circ}C$ and pH 6.5. The initial degradation rate and total removal efficiency increased with inoculum size. The strain also degraded dichloroacetic acid, which was supposed to be a degradation by-product. Phenol monooxygenase apparently participates in the TCE degradation mechanism.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.386-390
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• 2006

A green fluorescent protein-based Pseudomonas putida reporter was successfully constructed and shown to be capable of detecting oxidative stress. In this whole-cell reporter, the promoter of the paraquat-inducible ferredoxin-$NADP^+$ reductase (fpr) was fused to a promoterless gfp gene on a broad-host-range promoter probe vector. Pseudomonas putida KT2440 harboring this reporter plasmid exhibited an increased level of gfp expression in the presence of redox-cycling agents (paraquat and menadione), hydrogen peroxide, and potential environmental pollutant chemicals such as toluene, paint thinner, gasoline, and diesel. Induction of fpr in the presence of these chemicals was confirmed using Northern blot analysis.