• 제목/요약/키워드: pCBA

검색결과 34건 처리시간 0.027초

4-Chlorobenzoic Acid 분해유전자의 클로닝과 유전학적 특성 (Cloning and Characterization of the Genes Responsible for Degradation of 4-Chlorobenzoic Acid)

  • 이익근;김종우;김치경
    • 미생물학회지
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    • 제28권1호
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    • pp.41-46
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    • 1990
  • 자연환경으로부터 분리한 DJ-12 균주는 4CBA 및 4CB를 비롯하여 그 대사산물인 4OHBA와 PCA를 분해하여 단일 탄소원으로 이용하였다. DJ-12 균주에서 4CBA 및 4CB분해유전자는 약 65kb 크기의 plasmid인 pDJ121에 존재하였으며, 이 pDJ121은 ExoRI, HindIII, SalI 그리고 PslI의 절단부위를 각각 9, 11, 10 그리고 19개씩 가지고 있었다. EcoRI으로 처리한 pDJ121 절편을 pKT230에 ligation 시켜 재조합 vector인 pDK450을 만들었으며, 이를 Pseudomonas putida KT2440에 transformation 시켜 얻은 cloned cell 에서는 4CBA 분해유전자가 잘 발현되었다.

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PdRu/Carbon Composite 촉매를 이용한 테레프탈산의 수소화 정제 (Hydropurification of Crude Terephthalic Acid over PdRu/Carbon Composite Catalyst)

  • 정성화;박윤석
    • 대한화학회지
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    • 제46권1호
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    • pp.57-63
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    • 2002
  • CTA(crude terephthalic acid)의 수소화 정제 반응이 고온의 회분식반응기에서 PdRu/CCM(carbon-carbonaceous composite material) 촉매 상에서 수행되었다. 반응 시간에 따른 In(4-CBA; 4-carboxybenzaldehyde)의 의존도가 선형성을 보임에서 수소화 정제는 1차 속도론을 따름을 알 수 있었다. 촉매량에 따른 반응 속도의 선형성에서 조사된 반응 조건은 정제 반응을 잘 대변할 수 있음을 알 수 있었다. 반응 전환율이 증가하면(4-CBA가 감소하면) 고체 및 액체의 p-toluic acid(p-tol)의 농도는 증가하였으나 벤조산(BA)의 농도는 크게 변하지 않았다. 4-CBA 농도가 대략 0.15% 이하일 때에는 PTA의 AT(alkalitransmittance)는 4-CBA농도에 반비례하며 이는 4-CBA의 수소화에 따라 발색물질도 제거 됨을 보여 준다. 4-CBA농도가 약 0.2% 이상이면 AT는 일정하였는데 이는 4-CBA 자체는 발색 효과를 가지지 않음을 보여준다. (0.3%Pd-0.2%Ru)/CCM 촉매는 0.5%Pd/C 상업 촉매에 비해 초기 활성은 낮으나, 상업 공장 반응기에서 사용한 후에는 오히려 큰 잔존 활성을 보였고 PdRu/CCM 촉매는 루테늄 함량이 약 $0.2{\sim}0.35%$ 일 때 활성의 상승효과를 보였다. PdRu/CCM 촉매는 0.5%Pd/C 상업 촉매를 대체할 가능성이 높음을 알 수 있다.

평판배지법에 의한 4-chlorobenzoate 탈염소화 세균의 검색 (Identification of 4-Chlorobenzoate Dechlorinating Bacteria by Simple Plate Assay)

  • 채종찬;김치경;민경희;박용근
    • 한국미생물·생명공학회지
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    • 제23권1호
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    • pp.104-109
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    • 1995
  • The gene responsible for dechlorination of 4-chlorobenzoate (4CBA) was cloned in E. coli XL1-Blue from Pseudomonas sp. DJ-12. The cloned cell of E. coli Cjl had the hybrid pBluescript SK(+) plasmid, into which about 9.5 kb genomic DNA fragment of PseudOmonas sp. DJ-12 was inserted. The subclone of pCJlOl was constructed by inserting the 3.4 kb EcoRI-HindIII fragment of pCJl into the vector. Those cloned cells could be simply selected by halo formation around the colonies which was the precipitate of AgCl produced by reaction of AgNO$_{3}$ and chloride ion liberated by bacterial dechlorination of 4CBA- Such a plate assay method was standardized by the procedure that the colonies grown for 2 days on the Cl$^{-}$-free plate medium containing 1 mM 4CBA were flooded with 0.1 M AgNO$_{3}$ solution.

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Dechlorination of 4-Chlorobenzoate by Pseudomonas sp. DJ-12

  • Chae, Jong-Chan;Kim, Chi-Kyung
    • Journal of Microbiology
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    • 제35권4호
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    • pp.290-294
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    • 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.

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Genomic Analysis of the Extremely Halophilic Archaeon Halobacterium noricense CBA1132 Isolated from Solar Salt That Is an Essential Material for Fermented Foods

  • Lim, Seul Ki;Kim, Joon Yong;Song, Hye Seon;Kwon, Min-Sung;Lee, Jieun;Oh, Young Jun;Nam, Young-Do;Seo, Myung-Ji;Lee, Dong-Gi;Choi, Jong-Soon;Yoon, Changmann;Sohn, Eunju;Rahman, MD. Arif-Ur;Roh, Seong Woon;Choi, Hak-Jong
    • Journal of Microbiology and Biotechnology
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    • 제26권8호
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    • pp.1375-1382
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    • 2016
  • The extremely halophilic archaeon Halobacterium noricense is a member of the genus Halobacterium. Strain CBA1132 (= KCCM 43183, JCM 31150) was isolated from solar salt. The genome of strain CBA1132 assembled with 4 contigs, including three rRNA genes, 44 tRNA genes, and 3,208 open reading frames. Strain CBA1132 had nine putative CRISPRs and the genome contained genes encoding metal resistance determinants: copper-translocating P-type ATPase (CtpA), arsenical pump-driving ATPase (ArsA), arsenate reductase (ArsC), and arsenical resistance operon repressor (ArsR). Strain CBA1132 was related to Halobacterium noricense, with 99.2% 16S rRNA gene sequence similarity. Based on the comparative genomic analysis, strain CBA1132 has distinctly evolved; moreover, essential genes related to nitrogen metabolism were only detected in the genome of strain CBA1132 among the reported genomes in the genus Halobacterium. This genome sequence of Halobacterium noricense CBA1132 may be of use in future molecular biological studies.

Genetic Structure of xyl Gene Cluster Responsible for Complete Degradation of (4-Chloro )Benzoate from Pseudomonas sp. S-47

  • Park, Dong-Woo;Lee, Kyoung;Chae, Jong-Chan;Kudo, Toshiaki;Kim, Chi-Kyung
    • Journal of Microbiology and Biotechnology
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    • 제14권3호
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    • pp.483-489
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    • 2004
  • Pseudomonas sp. S-47 is a bacterium capable of degrading benzoate as well as 4-chlorobenzoate (4CBA). Benzoate and 4CBA are known to be degraded via a meta-cleavage pathway characterized by a series of enzymes encoded by xyl genes. The meta-cleavage pathway operon in Pseudomonas sp. S-47 encodes a set of enzymes which transform benzoate and 4CBA into TCA cycle intermediates via the meta-cleavage of (4-chloro )catechol to produce pyruvate and acetyl-CoA. In the current study, the meta-pathway gene cluster was cloned from the chromosomal DNA of S-47 strain to obtain pCS1, which included the degradation activities for 4CBA and catechol. The genetic organization of the operon was then examined by cloning the meta-pathway genes into a pBluescript SKII(+) vector. As such, the meta-pathway operon from Pseudomonas sp. S-47 was found to contain 13 genes in the order of xylXYZLTEGFlQKIH. The two regulatory genes, xylS and xylR, that control the expression of the meta-pathway operon, were located adjacently downstream of the meta-pathway operon. The xyl genes from strain S-47 exhibited a high nucleoside sequence homology to those from Pseudomonas putida mt-2, except for the xylJQK genes, which were more homologous to the corresponding three genes from P. stutzeri AN10. One open reading frame was found between the xylH and xylS genes, which may playa role of a transposase. Accordingly, the current results suggest that the xyl gene cluster in Pseudomonas sp. S-47 responsible for the complete degradation of benzoate was recombined with the corresponding genes from P. putida mt-2 and P. stutzeri AN10.

임플란트 고정체의 의원성 동요 후 골 유착 반응에 관한 연구 (Study of the re-osseointegration of implant fixture after mechanical unscrewing)

  • 장지훈;조진현;이청희
    • 대한치과보철학회지
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    • 제48권3호
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    • pp.209-214
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    • 2010
  • 연구 목적: 본 연구의 목적은 골 유착된 임플란트에 인위적 비틀림을 가한 후 골 유착이 다시 일어나는지, 혹은 일어나지 않는지, 일어난다면 이전의 골유착보다 강화되는지, 약화되는지에 대해 알아보기 위함이다. 연구 재료 및 방법:상업적으로 순수한 티타늄 (commercial pure titanium 99%)으로 직경 3.75 mm, 길이 4 mm의 표면처리 없는 실험용 임플란트를 제작하였다. 3.0 kg이상의 뉴질랜드산 흰색 암컷 토끼 7마리의 좌우 경골에 제작한 임플란트를 2개씩 식립 후, 6주의 골유착 유도 기간 부여 후 비틀림 제거력을 측정한 경우를 I군으로, 다시 임플란트 고정체를 재위치시키고 봉합하여 4주간의 치유기간을 더 두고 측정한 경우를 II군으로 분류하였다. 광학현미경을 이용한 조직 형태학적 분석을 위하여, 1차 비틀림 제거력 측정 직후 1마리의 토끼를 희생시키고, 2차 비틀림 제거력 측정 직후 2마리의 토끼를 희생시켜 각각 4개, 7개의 시편을 제작하여, 광학현미경 (${\times}20$) 분석에서 골-임플란트 접촉 (Bone-Implant contact, BIC, %)비율과 치밀골 부위에 위치하는 임플란트의 나사산 수를 측정하여 CBa (Bone area in the cortical passage)비율을 측정하였다. 비틀림 제거력과 BIC및 CBa비율에서의 I군과 II군의 통계적 유의성 ($\alpha$=.05)을 평가하였다. 결과: 비틀림 제거력 측정에서 I군은 $10.8{\pm}3.6$ NCm로 측정되었으며, II군은 $20.2{\pm}9.7$ NCm로 측정되었으며, I군보다II군의 비틀림 제거력이 평균 98.1% 증가되었다 (P<.05). 조직 형태학적 분석에서 BIC와 CBa 비율은 I군과 II군 사이에 통계적 유의성을 나타내지 않았고 (P>.05), RT/BIC와 RT/CBa 값은 I군과 II군 사이에 통계적 유의성을 나타냈다 (P<.05). 결론: 임플란트 고정체에 의원성 비틀림 동요가 발생한 경우에 초기 골유착을 얻기 위해 필요로 했던 치유기간보다 짧은 기간 내에 이전보다 견고한 골유착을 얻을 수 있을 것으로 생각된다.

폴리(페닐렌 설파이드)로 기능화된 다중벽 탄소나노튜브의 제조와 특성분석 (Preparation and Characterization of Poly(phenylene sulfide)-Functionalized MWNTs)

  • 홍성연;김영호
    • 폴리머
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    • 제38권6호
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    • pp.791-800
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    • 2014
  • Friedel-Crafts 직접 아실화 반응을 이용하여 $P_2O_5$/폴리인산 매질에서 다중벽 탄소나노튜브(MWNT)와 4-클로로벤조산(CBA)을 반응시켜 클로로벤조일(CB)기가 도입된 MWNT(c-MWNT)를 제조하였다. 이때 반응시키는 CBA양을 조절하여 염소원자 함량이 최대 5.3 wt%(CB기 함량 20.86 wt%)인 c-MWNT를 얻었다. 한편, 열가소성 엔지니어링 플라스틱 소재인 폴리(페닐렌 설파이드) (PPS)와 MWNT의 계면접착력을 증가시키기 위하여, 4-클로로벤젠티올(CBT)의 자기축합에 의한 PPS 중합시 c-MWNT를 함께 넣고 중합시킨 후 호모 PPS를 제거하여 MWNT-g-PPS를 얻었다. 이 MWNT-g-PPS의 열 및 표면 특성들을 분석하였으며, c-MWNT와 CBT가 반응하여 c-MWNT 표면에 PPS가 생성되었음을 확인하였다.

Improvement of 4-chlorobiphenyl degradation bya recombinant strain, pseudomonas sp. DJ12-C

  • Kim, Ji-Young;Kim, Young-Chang;You, Lim-Jai;Lee, Ki-Sung;Ok, Ka-Jong;Hee, Min-Kyung;Kim, Chi-Kyung
    • Journal of Microbiology
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    • 제35권1호
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    • pp.53-60
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    • 1997
  • Pseudomonas sp. P20 and Pseudomonas sp. DJ-12 isolated from the polluted environment are capable of degrading biphenyl and 4-chlorobiphenyl (4CB) to produce benzoic acid and 4-chlorobenzoic acid (4CBA) respectively, by pcbABCD-encoded enzymes. 4CBA can be further degraded by Pseudomonas sp. DJ-12, but not by Pseudomonas sp P20. However, the meta-cleavage activities of 2, 3-dihydroxybiphenyl (2, 3-DHBP) and 4-chloro-2, 3-DHBP dioxygenases (2, 3-DHBD) encoded by pcbC in Pseudomonas sp. P20 were stronger than Pseudomonas sp. DJ-12. In this study, the pcbC gene encoding 2, 3-DHBD was cloned from the genomic DNA of Pseudomonas sp. P20 by using pKT230. A hybrid plasmid pKK1 was constructed and E. coli KK1 transformant was selected by transforming the pKK1 hybrid plasmid carrying pcbC into E. coli XL1-Blue. By transferring the pKK1 plasmide of E. coli KK1 into Pseudomonas sp. DJ-12 by conjugation, a recombinant strain Pseudomonas sp. P20, Pseudomonas sp. DJ-12, and the recombinant cell assay methods. Pseudomonas sp. DJ12-C readily degraded 4CB and 2, 3-DHBP to produce 2-hydroxy-6-oxo-6-phenylhexa-2, 4-dienoic acid (HOPDA), and the resulting 4CBA and benzoic acid were continuously catabolized. Pseudomonas sp. DJ12-C degraded 1 mM 4CB completely after incubation for 20 h, but Pseudomonas sp. P20 and Pseudomonas sp. DJ-12 showed only 90% and Pseudomonas sp. DJ-12 had, but its degradation activity to 2, 3-DHBP, 3-methylcatechol, and catechol was improved.

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Isolation of pseudomonas sp. S-47 and its degradation of 4-chlorobenzoic acid

  • Seo, Dong-In;Lim, Jai-Yun;Kim, Young-Chang;Min, Kyung-Hee;Kim, Chi-Kyung
    • Journal of Microbiology
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    • 제35권3호
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    • pp.188-192
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    • 1997
  • The strain of S-47 degrading 4-chlorobenzoic acid (4CBA) was isolated from Ulsan chemical industrial complex by enrichment cultivation with 1 mM 4CBA. The strain was Gram-negative rod and grew optimally at 30.deg.C and pH 7 under aerobic condition, so that the organism was identified as a species of Pseudomonas. Pseudomonas sp. S-47 degraded 4-chlorobenzoic acid to produce a yellow-colored meta-cleavage product, which was confirmed to be 5-chloro-2-hydroxymuconic semialdehyde (5C-2HMS) by UV-visible spectrophotometry. 5C-3HMS was proved trometry. This means that Pseudomonas sp. S-47 degraded 4CBA via 4-chlorocatechol to 5C-2HMS by meta-cleavage reaction and then to 5C-2HMA by 5C-2HMS dehydrogenase.

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