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Pseudomonas putida SM 25의 Catechol 1,2-Dioxygenase의 부분정제와 이에 의한 cis,cis-Muconic Acid의 생성
김지연,김성태,강사욱,민경희 숙명여자대학교 환경과학연구소 1995 환경과학 Vol.2 No.-
Pseudomonas putida SM 25 로부터 catechol 1,2-dioxygenase를 ammonium sulfate precipitation, DEAE-sepharose A-50 CL-6B ion exchange chromatography, phenyl-sepharose CL-4B hydro-phobic chromatography 및 preparative gel permeation chromatography를 통해 정제배율 806.2배, 정제수율 10.6%로 부분정제하였다. Phenol, benzoate, catechol 및 salicylate가 효소를 유도하였으며, 그 중 5mM phenol이 가장 좋은 결과를 나타내었다. 이 효소는 catechol에 대해서는 우수한 효소 활성을 보였으나, 4-methylcatechol, pyrogallol 및 protocatechuate에 대해서는 거의 활성을 보이지 않았으며, catechol에 대한 Km 값은 7.8 M 이었다. 이 효소는 pH 7.5, 40℃에서 가장 높은 활성을 보였다. 이 효소는 pH 7.0∼11.0에서 안정하였으며, 열에 불안정하여 50℃에서 15분 내에 활성을 완전히 잃었고, thiol기 저해제에 의한 영향을 받지 않았다. 이 효소에 의한 catechol의 반응산물을 UV-visible spectroscopy, HPLC-diode array spectroscopy, GC-mass spectrometry로 분석한 결과 cis,cis-muconic acid로 확인되었다.
복수암 Sarcoma 180을 생쥐의 B 임파구 분화에 미치는 Ascorbate의 영향
강영준,노정혜,강사욱,정가진 大韓免疫學會 1993 大韓免疫學會誌 Vol.15 No.-
Ascorbate is one of the important radical scavengers. Its roles in biological system including anti-cancer effects have been broadly studied. Ascorbate recovered the function of B lymphocytes which was suppressed by Sarcoma 180-derived immunosuppressive factor(s). Production of anti-SRBC antidody was increased by the adminisration of ascorbate in the Sarcoma 180 culture supernatant-treated mice. Ascorbate enhanced the suppressed immune function of tumor-bearing hosts. Treatment of 1 mg of ascorbate increased the function of B lymphocytes, however, 10ug of ascorbate treatment decreased. In vitro treatment of ascorbate increased the immunoglobulin production ac-cording to the increasement of ascorbate concentration. These results also imply that ascorbate may be a immunoreeulatory molecule.
Cytochrome c550 is Related to Initiation of Sporulation in Bacillus subtilis
Sa-Ouk Kang,Han-Bong Ryu,Hyung-Soon Yim,Inji Shin 한국미생물학회 2005 The journal of microbiology Vol.43 No.3
The effect of cytochrome c550 encoded by cccA in Bacillus subtilis during the event of sporulation was investigated. The sporulation of cccA-overexpressing mutant was significantly accelerated, while disruptant strain showed delayed sporulation in spite of the same growth rate. Activity of sporulation stage-0-specific enzyme, extracellular α-amylase of mutant strains was similar to that of the control strain, but cccA-overexpressing mutant exhibited higher activity of stage-II-specific alkaline phosphatase and stage-III-specific glucose dehydrogenase when compared to deletion mutant and control strain. Northern blot analysis also revealed that cccA-overexpressing mutant showed high level of spo0A transcripts, while the disruptant rarely expressed spo0A. These results suggested that although cytochrome c550 is dispensable for growth and sporulation, expression of cccA may play an important role for initiation of sporulation through regulation of spo0A expression.
( Sa-ouk Kang ),( Min-kyu Kwak ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 Journal of microbiology and biotechnology Vol.31 No.1
γ-Glutamylcysteine synthetase (Gcs1) and glutathione reductase (Glr1) activity maintains minimal levels of cellular methylglyoxal in Candida albicans. In glutathione-depleted Δgcs1, we previously saw that NAD(H)-linked methylglyoxal oxidoreductase (Mgd1) and alcohol dehydrogenase (Adh1) are the most active methylglyoxal scavengers. With methylglyoxal accumulation, disruptants lacking MGD1 or ADH1 exhibit a poor redox state. However, there is little convincing evidence for a reciprocal relationship between methylglyoxal scavenger genes-disrupted mutants and changes in glutathione-(in)dependent redox regulation. Herein, we attempt to demonstrate a functional role for methylglyoxal scavengers, modeled on a triple disruptant (Δmgd1/Δadh1/Δgcs1), to link between antioxidative enzyme activities and their metabolites in glutathione-depleted conditions. Despite seeing elevated methylglyoxal in all of the disruptants, the result saw a decrease in pyruvate content in Δmgd1/Δadh1/Δgcs1 which was not observed in double gene-disrupted strains such as Δmgd1/Δgcs1 and Δadh1/Δgcs1. Interestingly, Δmgd1/Δadh1/Δgcs1 exhibited a significantly decrease in H<sub>2</sub>O<sub>2</sub> and superoxide which was also unobserved in Δmgd1/Δgcs1 and Δadh1/Δgcs1. The activities of the antioxidative enzymes erythroascorbate peroxidase and cytochrome c peroxidase were noticeably higher in Δmgd1/Δadh1/Δgcs1 than in the other disruptants. Meanwhile, Glr1 activity severely diminished in Δmgd1/Δadh1/Δgcs1. Monitoring complementary gene transcripts between double gene-disrupted Δmgd1/Δgcs1 and Δadh1/Δgcs1 supported the concept of an unbalanced redox state independent of the Glr1 activity for Δmgd1/Δadh1/Δgcs1. Our data demonstrate the reciprocal use of Eapx1 and Ccp1 in the absence of both methylglyoxal scavengers; that being pivotal for viability in non-filamentous budding yeast.
( Sa-ouk Kang ),( Min-kyu Kwak ) 한국미생물생명공학회 2024 Journal of microbiology and biotechnology Vol.34 No.2
Fifteen cyclic dipeptides (CDPs) containing proline, one cyclo(Phe-Ala) without proline, and a non-peptidyl DL-3-phenyllactic acid were previously identified in the culture filtrates of Lactobacillus plantarum LBP-K10, an isolate from kimchi. In this study, we used Japanese quail (Coturnix japonica) eggs to examine the effects of probiotic supplementation on the antimicrobial CDPs extracted from quail eggs (QE). Eggshell-free QE were obtained from two distinct groups of quails. The first group (K10N) comprised eggs from unsupplemented quails. The second group (K10S) comprised eggs from quails supplemented with Lb. plantarum LBP-K10. The QE samples were extracted using methylene chloride through a liquid-liquid extraction process. The resulting extract was fractionated into 16 parts using semi-preparative high-performance liquid chromatography. Two fractions, Q6 and Q9, were isolated from K10S and identified as cis-cyclo(L-Ser-L-Pro) and cis-cyclo(L-Leu-L-Pro). The Q9 fraction, containing cis-cyclo(L-Leu-L-Pro), has shown significant inhibitory properties against the proliferation of highly pathogenic multidrug-resistant bacteria, as well as human-specific and phytopathogenic fungi. Some of the ten combinations between the remaining fourteen unidentified fractions and two fractions, Q6 and Q9, containing cis-cyclo(L-Ser-L-Pro) and cis-cyclo(L-Leu-L-Pro) respectively, demonstrated a significant increase in activity against multidrug-resistant bacteria only when combined with Q9. The activity was 7.17 times higher compared to a single cis-cyclo(L-Leu-L-Pro). This study presents new findings on the efficacy of proline-containing CDPs in avian eggs. These CDPs provide antimicrobial properties when specific probiotics are supplemented.
Trichoderma koningii ATCC 26113으로부터 Xylanase 1의 순수분리 및 특성
Kim, Hyun-Ju,Kang, Sa-Ouk,Hah, Yung-Chil The Microbiological Society of Korea 1993 미생물학회지 Vol.31 No.1
A xylanase (xylanase I) was purified 11.9-fold from the culture filtrate of Trichoderma koningii ATCC 26113 by the column chromatography on Sephadex G-75, SP-Sephadex C-50, DEAE-Sephadex A-50 and Sephadex G-50 with an overall yield of 8.2%. The molecular mass determined by gel filtration and sodium dodecyl sulfate polyacrylamide gel electrophoresis was found to be a monomeric polypeptide of ca. 35 kDa. The isoelectric point of the enzyme was estimated to be 9.3. The optimal reaction pH and temperature are 5.8 and 55.deg.C, respectively. The enzyme is stable up to 60.deg.C, while 78% of its activity is lost after the incubation for 10 min at 70.deg.C. The enzyme hydrolyzes sylan with relatively high activity, as well as carboxymethyl cellulose and avicel. The $K_{m}$ values of the enzyme for oat-spelf sylan, larchwood xylan and Avicel were 3.5, 1.6 and 10. 1 mg/ml, respectively. The enzyme hydrolyzed oat-spelt sylan to sylose, sylobiose, sylotriose and arabionoxylobiose, while it degraded larchwood xylan to xylose, xylobiose, xylotriose and arabionoxylobiose, while it degraded larchwood xylan to xylose, xylobiose and xylotriose as the major products. The hydrolysis patterns indicate that xylanase I is endo-enzyme.e.