• 미생물학회지
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• 제38권4호
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• pp.245-245
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• 2002

Catabolic pathways for the degradation of various aromatics by Sphingomonas yanoikuyae Bl are intertwined, joining at the level of substituted benzoates, which are further degraded vita ring cleavage reactions. The mutant strain EK497, which was constructed by deleting a large DNA region containing most of the genes for biphenyl, naphthalene, m-xylene, and m-toluate degradation, was unable to grow on all of the aromatics tested except for benzoate as the sole source of carbon and energy.S. yanoikuyae EK497 was found to possess only catechol ortho-ring cleavage activity due to deletion of the genes for the meta-cleavage pathway. Wild-type S. yanoikuyae Bl grown on benzoate has both catechol orthoand meta-cleavage activity. However, m-xylene and m-toluate, which are metabolized through methylbenzoate, and biphenyl, which is metabolized through benzoate, induce only the meta-cleavage pathway, suggesting the presence of a substrate-dependent induction mechanism.

• Journal of Microbiology
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• 제38권4호
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• pp.245-249
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• 2000

Catabolic pathways for the degradation of various aromatics by Sphingomonas yanoikuyae Bl are intertwined, joining at the level of substituted benzoates, which are further degraded vita ring cleavage reactions. The mutant strain EK497, which was constructed by deleting a large DNA region containing most of the genes for biphenyl, naphthalene, m-xylene, and m-toluate degradation, was unable to grow on all of the aromatics tested except for benzoate as the sole source of carbon and energy.S. yanoikuyae EK497 was found to possess only catechol ortho-ring cleavage activity due to deletion of the genes for the meta-cleavage pathway. Wild-type S. yanoikuyae Bl grown on benzoate has both catechol orthoand meta-cleavage activity. However, m-xylene and m-toluate, which are metabolized through methylbenzoate, and biphenyl, which is metabolized through benzoate, induce only the meta-cleavage pathway, suggesting the presence of a substrate-dependent induction mechanism.

• Journal of Microbiology
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• 제38권2호
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• pp.53-61
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• 2000

Hydroxybenzoic acids are the most important intermediates in the degradative pathways of various aromatic compounds. Microorganisms catabolize aromatic compounds by converting them to hydroxylated intermediates and then cleave the benzene nucleus with ring dioxygenases. Hydroxylation of the benzene nucleus of an aromatic compound is an essential step for the initiation and subsequent disintegration of the benzene ring. The incorporation of two hydroxyl groups is essential for the labilization of the benzene nucleus. Monohydroxybenzoic acids such as 2-hydroxybenzoic acid, 3-hydroxybenzoic acid, and 4-hydrosybenzoic acid, opr pyrocattechuic acid that are susceptible for subsequent oxygenative cleavage of the benzene ring. These terminal aromatic intermediates are further degraded to cellular components through ortho-and/or meta-cleavage pathways and finally lead to the formation of constituents of the TCA cycle. Many groups of microorganisms have been isolated as degraders of hydroxybenzoic acids with diverse drgradative routes and specific enzymes involved in their metabolic pahtway. Various microorganisms carry out unusual non-oxidative decarboxylation of aromatic acids and convert them to respective phenols which have been documented. Futher, Pseudomonas and Bacillus spp. are the most ubiquitous microorganisms, being the principal components of microflora of most soil and water enviroments.

• Journal of Microbiology and Biotechnology
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• 제10권1호
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• pp.111-114
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• 2000

Streptomyces are widespread in nature and play a very important role in the biosynthesis as well as biodegradation of natural and unnatural aromatic compounds. Both qualitatively and quantitatively through TLC and UV spectrophotometric assays, it was observed that the thermophilic soil bacteria S. setonii (ATCC 39116), which can utilize a benzoate as a sole carbon and energy source in a minimal liquid culture, was not very sensitive to the benzoate concentation and to the culture conditions such as the pH and temperature. The in vitro conversion of a catechol to a cis, cis-muconic acid by a crude S. setonii lysate implies that the aromatic ring cleavage by S. setonii is initiated by a thermostable catechol-1,2-dioxygenase, the key enzyme in the ortho-cleavage pathway of aromatic compound biodegradation. Unlike non-degrading S. lividans, S.setonii was also highly resistant to other similar hazardous aromatic compounds, exhibiting almost no adverse effect on its growth in a complex liquid culture.

• Journal of the Korean Wood Science and Technology
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• 제45권2호
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• pp.168-181
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• 2017

Whole cell of Phanerochaete chrysosporium with reducing agent was applied to verify the degradation mechanism of aromatic compounds derived from lignin precisely. Unlike the free-reducing agent experiment, various degraded products of aromatic compounds were detected under the fungal treatment. Our results suggested that demethoxylation, $C_{\alpha}$ oxidation and ring cleavage of aromatic compounds occurred under the catabolic system of P. chrysosporium. After that, degraded products stimulated the primary metabolism of fungus, so succinic acid was ultimately main degradation product of lignin derived-aromatic compounds. Especially, hydroquinone was detected as final intermediate in the degradation of aromatics and production of succinic acid. In conclusions, P. chrysosporium has an unique catabolic metabolism related to the production of succinic acid from lignin derived-aromatic compounds, which was meaningful in terms of lignin valorization.

• 생명과학회지
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• 제19권5호
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• pp.659-663
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• 2009

장기간 경유로 오염된 지역의 토양으로부터 분리한 세균 3Y는 석유계 탄화수소를 구성하는 다양한 화합물을 유일 탄소원으로하여 성장하였다. Sphingomonas sp. 3Y는 지방족 화합물은 물론이고 방향족 화합물을 이용해서 성장할 수 있었다. 지방족 화합물로서는 hexane과 hexadecane을 이용하여 성장하였고, 한편 방향족 화합물로서는 BTEX는 물론이고 phenol, biphenyl, 또는 phenanthrene을 유일 탄소원으로 이용하여 성장하였다. 본 균주는 indole과 catechol을 이용한 실험결과 방향족 탄화수소의 생분해 과정에서 맨 첫 단계 반응에 관여하는 효소인 aromatic ring dioxygenase 활성과 benzene 환을 깨는 효소인 meta-cleavage dioxygenase 활성을 나타내었다. Sphingomonas sp. 3Y의 16S rRNA 유전자의 염기서열 분석과 계통수 작성 결과 본 균주는 ${\alpha}$-Proteobacteria인 Sphingomonas속에 해당하였으며 지금까지 잘 알려진 석유계 탄화수소를 분해하는 Sphingomonas sp. 균주들과는 다른 cluster를 형성하였다. 다양한 석유계 탄화수소 성분을 이용하여 성장하는 Sphingomonas sp. 3Y는 유류로 오염된 토양의 복원에 유용하게 사용될 것으로 여겨지며 이 균주의 최적 분해 조건을 조사한다면 그 결과는 이 균주가 분리된 오염지역의 생물학적 분해를 최적화하는데 기여할 것이다.

• Journal of Forest and Environmental Science
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• 제6권1호
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• pp.45-60
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• 1989

리그닌 생분해의 분해경로 및 매카니즘에 관한 연구가 최근 Kirk와 Higuchi 등에 의하여 활발히 연구되고 있다. 특히, Phanerochaete chrysosporium이 생산해내는 Lignlnase를 이용하여 매우 가치있는 연구 결과를 얻고 있다. 본 총설에서는 Kirk와 Higuchi의 허가를 얻어서 그들의 논문을 중심으로 리그닌의 중요한 결합 양식 별로 즉, ${\beta}$-O-4, ${\beta}$-5, ${\beta}$-1, ${\beta}$-6, 5-5 등의 결합 모델 화합물들의 분해경로 및 매카니즘에 관하여 조사 정리하였다.

• Journal of Microbiology and Biotechnology
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• 제8권3호
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• pp.264-269
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• 1998

Commamonas acidovorans SMN4 showed wide growth substrate spectra for various aromatic hydrocarbons. Strain SMN4 was able to grow on biphenyl producing a meta-cleavage compound, yellow 2-hydroxy-6-oxophenylhexa-2,4-dienoic acid with a spray of 2,3-dihydroxybiphenyl, while it also grew on catechol, developing yellow 2- hydroxymucoic semialdehyde with a spray of 100 mM catechol. Thus these results indicate that two-ring structures of biphenyl were cleaved by meta-mode in upper and lower pathways. Strain SMN4 metabolized various substituted biphenyl compounds and xylene to the corresponding benzoate derivatives through oxidation of the ring structures. It was clearly shown that biphenyl can be a common inducer in the oxidation of biphenyl and 2,3-dihydroxybiphenyl. Various compounds were examined for their suitability to serve as substrates for indole oxidation, indicating that biphenyl, benzoate, and succinate are quite good inducers of indigo production due to the activity of biphenyl dioxygenase. This results suggest that indigo formation is by means of the combined activities of biphenyl dioxygenase and tryptophanase.

• Elastomers and Composites
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• 제43권1호
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• pp.31-38
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• 2008

[ $FeCl_3$ ]를 첨가한 초음파 조건에서 4-nitroaniline, 3-nitroaniline, and 4-isopropylaniline등의 방향족 아민 화합물과 풀러렌 산화물$[C_{70}(O)_n](n\geq1)$을 반응시켰다. 이 반응은 방향족 아민 화합물을 사용한 풀러렌 산화물 쪼개짐 반응이다. MALDI-TOF-MS and UV-vis spectra를 사용하여 생성된 화합물이 아민화 풀러렌 유도체임을 확인하였다.

• Journal of Microbiology
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• 제43권4호
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• pp.325-330
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• 2005

Rhodococcus sp. strain YU6 was isolated from soil for the ability to grow on o-xylene as the sole carbon and energy source. Unlike most other o-xylene-degrading bacteria, YU6 is able to grow on p-xylene. Numerous growth substrate range experiments, in addition to the ring-cleavage enzyme assay data, suggest that YU6 initially metabolizes 0- and p-xylene by direct aromatic ring oxidation. This leads to the formation of dimethylcatechols, which was further degraded largely through meta-cleavage path-way. The gene encoding meta-cleavage dioxygenase enzyme was PCR cloned from genomic YU6 DNA using previously known gene sequence data from the o-xylene-degrading Rhodococcus sp. strain DK17. Subsequent sequencing of the 918-bp PCR product revealed a $98\%$ identity to the gene, encoding meth-ylcatechol 2,3-dioxygenase from DK17. PFGE analysis followed by Southern hybridization with the catechol 2,3-dioxygenase gene demonstrated that the gene is located on an approximately 560-kb megaplasmid, designated pJY J1