• KSBB Journal
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• 제13권5호
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• pp.561-568
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• 1998

Two cometabolic trichloroethylene (TC) degraders, Pseudomonas putida F1 and Burkholderia (Pseudomonas) cepacia G4, were found to catabolize phenol, benzene, toluene, and ethylbenzene as carbon and energy sources. Resting cells of P. putida F1 and B. cepacia G4 grown in the presence of toluene and phenol, respectively, were able to degrade not only benzene, toluene and ethylenzene but also TCE and p-xylene. However, these two strains grown in the absence of toluene or phenol did not degrade TCE and p-xylene. Therefore, it was tentatively concluded that cometabolic degradation of TC and p-xylene was mediated by toluene dioxygenase (P. putida F1) or toluene-2-monooxygenase (B. cepacia G4). Maximal degradation rates of BTEX and TCE by toluene- and phenol-induced resting cells of P. putida F1 and B. cepacia G4 were appeared to be 4-530 nmol/(min$.$mg cell protein) when a single compound was solely served as a target substrate. In case of double substrates, the benzene degradation rate by P. putida F1 in the presence of toluene was decreased up to one seventh of that for the single substrate. TCE degradation rate was also linearly decreased as toluene concentration increased. On the other hand, toluene degradation rate was enhanced by benzene and TCE. For B. cepacia G4, degradation rates of TCE and toluene increased 4 times in the presence of 50 ${\mu}$M phenol. From these results, it was concluded that a degradation rate of a compound in the presence of another cosubstrate(s) could not be predicted by simply generalizing antagonistic or synergistic interactions between substrates.

• 한국균학회지
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• 제25권1호통권80호
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• pp.10-19
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• 1997

무우품종(Raphanus sativus L.) Saxa Nova에 시들음병을 일으키는 Fusarium oxysporum f. sp. raphani (FOR)에 대해 저항성을 증가시켜 방제효과를 얻기 위하여 식물성장을 증진시키는 것으로 알려진 Pseudomonas florescens WCS374 (WCS 374), P. putida RE10 (RE10) 및 Pseudomonas sp. EN41S (EN415)을 병원균처리 토양에 단독 또는 혼합처리하여 4주간 폿트배양한 후 무우에 나타나는 외부 및 내부병징을 조사하여 처리세균에 의한 병억제 효과를 측정하였다. 내부 및 외부병징으로 대조구는 각각 46.5% 및 21.1%를 나타내었고, RE10처리는 내외병징이 각각 12.2%와 7.8%로 발병이 억제됨을 알 수 있었다. 그러나 발병억제력이 높다고 알려진 WCS374는 내외 병징이 각각 45.6%와 27.8%로 나타났다. 한편 RE10균주를 WCS374 또는 EN415 균주와 혼합하여 처리할 경우 내외 병징이 10.0-22.1% 정도이었고 EN415와 혼합처리하면 7.8-20.2%의 병징을 나타낸다. FOR의 뿌리점유율은 뿌리에서 $2.4-5.1{\times}10^3/g$였고 토양내 분포수는 $0.7-1.3{\times}10^3/g$이었다. 대조구는 뿌리에서 $3.8{\times}10^3/g$였으며 RE10의 처리는 $2.9{\times}10^3/g$로 분포수가 적었고, 3종 세균의 혼합처리는 $5.1{\times}10^3/g$으로 많이 관찰되었으나, 처리간에 통계적 차이는 없었다. 토양에서 관찰된 FOR은 부리부분 보다 그 분포 수가 적었다. 처리된 3가지 세균은 뿌리에서 $2.3-4.0{\times}10^7/g$ 범위이고, 토양에서는 $0.9-1.8{\times}10^7/g$으로 뿌리에서 관찰된 수 보다 적게 분포하였다. 뿌리부분에서 대조구나 RE10의 처리토양은 형광성 Pseudomonas spp.의 분포수가 적고 처리간에는 통계적 차이를 나타냈으나, 토양조사에서 이세균은 큰 차이를 나타내지 않았다. 뿌리에 처리된 세균과 FOR의 분포수는 토양에 처리된 것과 대조하였을 때 많았으며, 이 실험 에 사용된 RE10과 EN415은 Fusarium시들음병에 대한 기주의 저항성을 유도하는 것으로 생각된다.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2000년도 International Meeting 2000
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• pp.79-86
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• 2000

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.320-320
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• 2000

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권1호
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• pp.34-39
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• 2005

Trichloroethylene (TCE) is an environmental contaminant provoking genetic mutation and damages to liver and central nerve system even at low concentrations. A practical scheme is reported using toluene as a primary substrate to revitalize the biofilter column for an extended period of TCE degradation. The rate of trichloroethylene (TCE) degradation by Pseudomonas putida F1 at $25^{\circ}C$ decreased exponentially with time, without toluene feeding to a biofilter column ($11\;cm\;I.D.{\times}95\;cm$ height). The rate of decrease was 2.5 times faster at a TCE concentration of $970\;{\mu}g/L$ compared to a TCE concentration of $110\;{\mu}g/L$. The TCE itself was not toxic to the cells, but the metabolic intermediates of the TCE degradation were apparently responsible for the decrease in the TCE degradation rate. A short-term (2 h) supply of toluene ($2,200\;{\mu}g/L$) at an empty bed residence time (EBRT) of 6.4 min recovered the relative column activity by $43\%$ when the TCE removal efficiency at the time of toluene feeding was $58\%$. The recovery of the TCE removal efficiency increased at higher incoming toluene concentrations and longer toluene supply durations according to the Monod type of kinetic expressions. A longer duration ($1.4{\sim}2.4$ times) of toluene supply increased the recovery of the TCE removal efficiency by $20\%$ for the same toluene load.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.351-354
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• 2003

• Journal of Microbiology
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• 제44권2호
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• pp.192-199
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• 2006

Pseudomonas putida KL47 is a natural isolate that assimilates benzene, 1-alkylbenzene $(C_1-C_4)$, biphenyl, p-cumate, and p-cymene. The genetic background of strain KL47 underlying the broad range of growth substrates was examined. It was found that the cym and cmt operons are constitutively expressed due to a lack of the cymR gene, and the tod operon is still inducible by toluene and biphenyl. The entire array of gene clusters responsible for the catabolism of toluene and p-cymene/p-cumate has been cloned in a cosmid vector, pLAFR3, and were named pEK6 and pEK27, respectively. The two inserts overlap one another and the nucleotide sequence (42,505 bp) comprising the cym, cmt, and tod operons and its flanking genes in KL47 are almost identical (>99 %) to those of P. putida F1. In the cloned DNA fragment, two genes with unknown functions, labeled cymZ and cmtR, were newly identified and show high sequence homology to dienelactone hydrolase and CymR proteins, respectively. The cmtR gene was identified in the place of the cmtI gene of previous annotation. Western blot analysis showed that, in strains F1 and KL47, the todT gene is not expressed during growth on Luria Bertani medium. In minimal basal salt medium, expression of the todT gene is inducible by toluene, but not by biphenyl in strain F1; however, it is constantly expressed in strain KL47, indicating that high levels of expression of the todST genes with one amino acid substitution in TodS might provide strain KL47 with a means of adaptation of the tod catabolic operon to various aromatic hydrocarbons.

• 한국토양비료학회지
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• 제21권1호
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• pp.41-47
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• 1988

토양중(土壤中) 향광색소생성세균(螢光色素生成細菌)에서 형성(形成)되는 3가철등(價鐵等)의 양(陽) ion 결합물질(結合物質)인 Siderophore 생성(生成)이 토양부생성사상균(土壤腐生成絲狀菌)의 생육(生育) 및 $Fe^{3+}$와 $Mn^{2+}$의 흡수이용(吸收利用)에 관(關)한 영향(影響)을 밝히고저 실내실험(室內實驗)한 결과(結果)는 다음과 같다. 1. 형광색소생성(螢光色素生成) 토양세균(土壤細菌)인 Pseudomonas putida Pt-II의 인공배지(人工培地)에 접종(接種)은 Siderophore 생성(生成)을 증가(增加)시켰다. 2. 경시적(徑時的) Siderophore 생성량(生成量)은 3가철(價鐵)의 첨가(添加)로 감소(減少)되었으며 철결합물질(鐵結合物質)인 EDDHA와 유사(類似)한 작용(作用)을 보였다. 3. Siderophore 농도(濃度)의 증가(增加)는 토양부생성(土壤腐生性) 사상균(絲狀菌)의 생육(生育)을 억제(抑制)하였으며 억제(抑制)의 정도(程度)는 독소생성(毒素生成) 사상균(絲狀菌)인 Stachybotrys chatarum과 F. solani에서 강(强)하였으나 F. oxysporum에 대해서는 억제력(抑制力)이 약(弱)하였다. 4. 인공배지내(人工培地內)에서 $Mn^{2+}$의 농도변화(濃度變化)는 Siderophore 생성(生成)에 영향(影響)하지 못하였으나 토양부생성사상균(土壤腐生性絲狀菌)의 생체중(生體重) 증가(增加)와는 정상관관계(正相關關係)를 보였음.

• 환경위생공학
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• 제14권1호
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• pp.24-30
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• 1999

A biological filter for treatment of toluene among volatile organic compounds was studied. The investigation was conducted using specially built stainless steel columns packed with granular activated carbon and cold for removal of toluene. The G.A. and mold as filter material was also coated with Pseudomonas putida microorganisms.The biofilter unit was operated in the condition of moisture content vairation at gas loading rate of 12.5 l/min. Gaseous toluene taken from tedlar bag was analyzed by the use of G.C equipped with F.I.d detector. The removal efficiency of gaseous toluene was 95% at average inlet concentration of 950 ppm during bio-degradation operating condition. Effective removal efficiency was obtained with moisture content 27.5% at activated carbon and 32% at mold in this study. The effective operating condition were obtained with pH 6-8, temperature 28-42℃ for microbial degradation at gas loading rate of 12.5 l/min in packed material.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.207-208
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• 2000

Since trichloroethylene (TCE), dichloroethylene (DCE), and vinyl chloride (VC) arise from anaerobic degradation of tetrachloroethylene (PCE) and TCE, there is interest in creating aerobic remediation systems that avoid the highly toxic VC and cis-DCE which predonominate in anaerobic degradation. However, it seemed TCE could not be degraded aerobically without an inducing compound (which also competitively inhibits TCE degradation). It has been shown that TCE induces expression of both the toluene dioxygenase of p. putida F1 as well as toluene-p-monooxygenase of P.mendocina KRI. We investigated here the ability of PCE, TCE, and chlorinated phenols to induce toluene-o-xylene monooxygenase (ToMO) from P.stutzeri OX1. ToMO has a relaxed regio-specificity since it hydroxylates toluene in the ortho, meta, and para positions; it also has a broad substrate range as it oxidizes o-xylene, m-xylene, p-xylene, toluene, benzene, ethylbenzene, styrene, and naphthalene; chlorinated compounds including TCE, 1, 1-DCE, cis-DCE, trans-DCE, VC, and chloroform : as well as mixtures of chlorinated aliphatics (Pseudomonas 1999 Maui Meeting). ToMO is a multicomponent enzyme with greatest similarity to the aromatic monooxygenases of Burkholderia pickettii PKO1 and P.mendocina KR1. Using P.sturzeri OX1, it was found that PCE induces P.mendocina KR1 Using P.situtzeri OX1, it was found that PCE induces ToMO activity measured as naphthalene oxygenase activity 2.5-fold, TCE induces 2.3-fold, and toluene induces 3.0 fold. With the mutant P.stutzeri M1 which does not express ToMO, it was also found there was no naphthalene oxygenate activity induced by PCE and TCE; hence, PCE and TCE induce the tow path. Using P.putida PaW340(pPP4062, pFP3028) which has the tow promoter fused to the reporter catechol-2, 3-dioxygenase and the regulator gene touR, it was determined that the tow promoter was induced 5.7-, 7.1-, and 5.2-fold for 2-, 3-, 4-chlorophenol, respectively (cf. 8.9-fold induction with o-cresol) : however, TCE and PCE did not directly induce the tou path. Gas chromatography and chloride ion analysis also showed that TCE induced ToMO expression in P.stutzeri OX1 and was degraded and mineralized. This is the first report of significant PCE induction of any enzyme as well as the first report of chlorinated compound induction of the tou operon. The results indicate TCE and chlorinated phenols can be degraded by P.stutzeri OX1 without a separate inducer of the tou pathway and without competitive inhibition.