• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.390-392
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• 2003

Pseudomonas savastanoi BCNU 106은 mineral salt medium에서 30 mM trichloroacetic acid의 농도까지 유일한 탄소원으로 이용하여 생육할 수 있다는 것을 발견하였다. 또한 trichloroacetic acid 뿐만 아니라 monochloroacetic acid, trichloroethylene, p-dichlorobenzene을 유일한 탄소원으로 이용 가능하였다. 그러나 이들 화합물에 대한 내성시험결과 전혀 내성이 없는 것을 알게 되었다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.386-389
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• 2003

Pseudomonas savastanoi BCNU 106은 o-xylene 뿐만 아니라 m-, p-xylene을 분해할 수 있는 능력을 나타내었고, 비교적 높은 농도인 10 mM toluene, 2 mM o-xylene, 10 mM m-xylene, 10 mM p-xylene에서 높은 분해율을 보여주었다. Pseudomonas savastanoi BCNU 106의 resting cell을 이용하여 o-xylene의 중간대사산물을 GC-MS를 통하여 조사하였다. 주로 2-methylbenzyl alcohol, 2-methylbenzoic acid 등이 발견되었다.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2007년도 제48회 학술심포지움 및 추계국제학술대회
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• pp.67.1-67.1
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• 2007

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• Journal of Microbiology and Biotechnology
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• 제28권9호
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• pp.1502-1510
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• 2018

Organic solvent-tolerant (OST) enzymes are widely applied in various industries for their activity and stability in organic solvents, for their higher substrate solubility, and for their greater stero-selectivity. However, the criteria for identifying OST enzymes largely remain undefined. In this study, we compared the amino acid composition of 19 OST esterases with that of 19 non OST esterases. OST esterases have increased the ratio of Ala and Arg residues and decreased the ratio of Asn, Ile, Tyr, Lys, and Phe residues. Based on our amino acid composition analysis, we cloned a carboxylesterase (EstSP2) from a psychrophilic bacterium, Sphingomonas glacialis PAMC 26605, and characterized its recombinant protein. EstSP2 is a substrate specific to p-nitrophenyl acetate and hydrolyzed aspirin, with optimal activity at $40^{\circ}C$; at $4^{\circ}C$, the activity is approximately 50% of its maximum. As expected, EstSP2 showed tolerance in up to 40% concentration of polar organic solvents, including dimethyl sulfoxide, methanol, and ethanol. The results of this study suggest that selecting OST esterases based on their amino acid composition could be a novel approach to identifying OST esterases produced from bacterial genomes.

• 한국막학회:학술대회논문집
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• 한국막학회 1991년도 추계 총회 및 학술발표회
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• pp.9-16
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• 1991

The current status of reverse osmosis and ultrafiltration membranes are reviewed with the view for the future. In the case of reverse osmosis (RO) membranes, as examples, new crosslinked aromatic polyamide membranes exhibited the superior separation performance with the sufficient water permeability, the high tolerance for oxidizing agents and chemicals. Ultrafiltration (UF) membrane based on poly(phenylene sulfide sulfone) (PPSS) also exibited the superior separation performance with the high solvent, heat and fouling resistance.

• Applied Biological Chemistry
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• 제36권1호
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• pp.38-44
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• 1993

1) OBT mutant는 Clostridium saccharoperbutylacetonicum ATCC 13564(N1-4주(株))로부터 UV light와 butanol tolerance에 의해 분리했다. 동 돌연변이주(株)는 16.46g/l(1.4배 증가)의 부타놀과 4.6g/l(1.5배 증가)의 아세톤을 생산하고 전체 용매는 21.47g/l를 생산했다. 이 결과는 n-butanol을 생산하는 clostridial bacteria에서 error-prone pathway를 통한 misrepair의 약한 효과가 UV light와 butanol tolerance에 의해서 극복되었다는 것을 제시했다. 2) glucose 발효에 비교해서 mannitol 발효에서 OBT mutant는 acetone과 acetic acid는 생산되지 않았다. 전체용매에 대한 n-butanol과 ethanol의 비는 각각 10.3%와 10.6%씩 증가되었고 전체적으로는20.9% 증가된 반면, acetone의 비는 21.2%가 감소되었다. 또한 전체 용매에 대한 n-butanol의 최대비는 94.8%까지 증가하였다. 이들 결과는 산화합물(acetone, acetic acid, butyric acid)이 환원화합물(n-butanol, ethanol)로 전환된 것을 의미했다. 따라서 mannitol은 부산물인 산화합물을 제거하는데 사용할 수 있다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.801-806
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• 2003

Pseudomonas sp. BCNU 106 accumulated approximately 4.12 mM trehalose after cultivation of 12 hr probably by the arising action of trehalose-6-phosphate synthase/phosphatase. The cDNA clones of trehalose-6-phosphate synthase/ phosphatase were isolated from Pseudomonas sp. BCNU 106, and named as PsTPS and PsTPP(Pseudomonas sp. BCNU 106 trehalose-6-phosphate synthase/phosphatase). The two mRNA levels of trehalose-6-phosphate synthase/ phosphatase peaked at 12 hr after exposure to toluene, and thereafter were declined slightly These results support an important role of trehalose accumulation by expressions of PsTPS and PsTPP in toluene-tolerance of Pseudomonas sp. BCNU 106.

• 생명과학회지
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• 제30권1호
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• pp.88-95
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• 2020

유기용매 내성 세균인 Pseudomonas sp. BCNU 106을 10%(v/v) 톨루엔에 노출시킨 후 8시간 동안 random arbitrarily primed polymerase chain reaction (RAP-PCR)기법을 이용하여 메신져 RNA 발현 레벨을 조사하였다. 총 100개의 상향발현된 발현 산물 중에서 50개의 상보적인 단편들이 반복적으로 재현성있게 발현되는 것으로 확인되어, 이들을 클로닝을 하였으며 나아가 유전자 염기서열을 결정하였다. Blast analysis 결과, 톨루엔은 LysR family transcriptional regulator 그리고 RNA polymerase factor sigma-32같은 전사와 관련된 유전자들의 발현 레벨을 적응적으로 증가시키는 것으로 확인되었다. 그리고 톨루엔 스트레스 존재 하에서 inorganic ion 수송과 대사와 관련된 catalase와 Mn²⁺/Fe²⁺ transporter 유전자의 발현이 증가되었으며, 신호전달과 대사와 기능적으로 관련된 type IV pilus assembly PilZ와 multi-sensor signal transduction histidine kinase 유전자들의 발현 증가도 확인되었다. 한편 톨루엔 노출 후 탄수화물 수송과 대사와 관련된 beta-hexosaminidase 유전자발현 레벨이 증가하였다. 나아가 DNA polymerase III subunit epsilon, DNA-3-methyladenine glycosylase II와 DEAD/DEAH box helicase domain-containing 유전자들과 같은 DNA 복제, 재조합 그리고 수복에 관련성이 있는 유전자들의 발현 레벨 그리고 심지어는 ABC transporter 유전자와 같은 방어 메커니즘에 관련성이 있는 유전자들의 발현 레벨이 적응적으로 증가되는 것으로 밝혀졌다. 특히 10% 톨루엔 존재하에서 ABC transportor, Mn²⁺/Fe²⁺ transporter 및 β-hexosaminidase 유전자에 해당하는 RNA들이 괄목하게 유도되는 것이 확인되었다. 그러므로 유기용매 내성 세균 Pseudomonas sp. BCNU 106이 유기용매에 대하여 내성을 나타내는데 있어서 방어 메커니즘, 세포내 이온 항상성 그리고 바이오 필름 형성이 필수적인 것으로 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제18권4호
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• pp.663-669
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• 2008

The solvent-tolerant bacterium Enterobacter sp. VKGH12 is capable of utilizing n-butanol and contains an $NAD^+$-dependent n-butanol dehydrogenase (BDH). The BDH from n-butanol-grown Enterobacter sp. was purified from a cell-free extract (soluble fraction) to near homogeneity using a 3-step procedure. The BDH was purified 15.37-fold with a recovery of only 10.51, and the molecular mass estimated to be 38 kDa. The apparent Michaelis-Menten constant ($K_m$) for the BDH was found to be 4 mM with respect to n-butanol. The BDH also had a broad range of substrate specificity, including primary alcohols, secondary alcohols, and aromatic alcohols, and exhibited an optimal activity at pH 9.0 and $40^{\circ}C$. Among the metal ions studied, $Mg^{2+}$ and $Mn^{2+}$ had no effect, whereas $Cu^{2+},\;Zn^{2+}$, and $Fe^{2+}$ at 1 mM completely inhibited the BDH activity. The BDH activity was not inhibited by PMSF, suggesting that serine is not involved in the catalytic site. The known metal ion chelator EDTA had no effect on the BDH activity. Thus, in addition to its physiological significance, some features of the enzyme, such as its activity at an alkaline pH and broad range of substrate specificity, including primary and secondary alcohols, are attractive for application to the enzymatic conversion of alcohols.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권1호
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• pp.53-56
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• 2000

A thermostable esterase from the hyper thermophilic archaeon Sulfolobus solfataricus was partially purified 590-fold with $16.2\%$ recovery. The partially purified esterase had a specific activity of $29.5\;{\mu}mol\;min^{-1}mg^{-1}$ when the enzyme activity was determined using p-nitrophenyl butyrate as a substrate. The apparent molecular weight was about 100 kDa, while the optimum temperature and pH for esterase were $75^{\circ}C$ and 8.0, respectively. The enzyme showed high thermal stability and solvent tolerance in comparison to its mesophilic counterpart. The enzyme also showed chiral resolution activity for (S)-ibuprofen, indicating that S. solfataricus esterase can be used for the production of commercially important chiral drugs.