카드뮴이 카드뮴 내성 효모세포내의 효소 활성에 미치는 영향

유대식,박은규,박정문 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.3

카드뮴에 의하여 고도 카드뮴 내성 효모인 Hansenula anomala B-7 세포내 효소생성의 변화를 관찰하여 대사계의 변화를 추정했다. 1.0mM 카드뮴에 의하여 공시균의 alcohol dehydrogenase의 생성은 무첨가에 비하여 90% 이상 감소하나 malate dehydrogenase의 생성은 440% 증가되어, 카드뮴에 의하여 혐기적 대사계는 억제되고 호기적 대사계인 TCA 회로는 활성화되었다. 그리고 1.0 mM 카드뮴에 의하여 공시균의 해당계 효소인 phosphofructokinase의 생성은 약 40% 감소되었으나, 당의 호기적 분해대사계 효소인 6-phosphogluconate dehydrogenase의 생성은 약 136% 증가되어, 카드뮴에 의하여 EMP 대사계는 활성화되었다. 더욱이 1.0 mM 카드뮴에 의하여 공시균의 cytochrome c oxidase와 alkaline phosphatase의 생성의 각각 260%와 155% 증가되었다. 이상의 결과를 종합하면 카드뮴에 의하여 혐기적 대사계는 억제되나, 호기적 대사계는 활성화되며, 이로 인하여 생성된 다량의 NADH와 NADPH의 산화를 위하여 cytochrome c oxidase의 활성화는 필연적으로 요구되었다. 그리고 pyrimidine nucleotide 분해대사계 효소인 cytidine deaminase의 생성은 1.0mM 카드뮴에 의하여 약 86% 감소되어, 카드뮴은 necleotide 분해를 억제한다고 추측할 수 있었다. An extremely cadmium tolerant yeast, Hansenula anomala B-7 used to determine the modification of the intracellular enzyme activities by cadmium ion. The activities of alcohol dehydrogenase, phosphofructokinase, and cytidine deaminase were decreased up to 90%, 40%, and 86% compared with the control by mM cadmium nitrate respectively, but the activites of malate dehydrogenase, 6-phosphogluconate dehydrogenase, cytochrome c oxidase, and alkaline phosphatase were increased up to 440%, 136%, 260% and 155% compared with the control by 1 mM cadmium nitrate respectively. These show that the activities of the enzymes participating in Emboden-Mayerhof pathway (e.g. anaerobic metabolism) were reduced by cadmium, but those involved in hexose monophosphate pathway and tricarboxylic acid cycle (e.g. aerobic metabolism) were stimulated in contrast. It has been suggested that the diminished activity of cytideine deaminase in pyrimidine nucleotide dissimilation occured due to the inhibited nucleotide dissimilation by cadmium ion; the enhanced activity of cytochrome c oxidase was specifically required in order to oxidize a raised amount of NADH and NADPH due to the increased aerobic metabolism.

Cadmium에 대한 Metallothionein 및 Free Radical Scavenger에 관한 최근의 연구 동향

김영숙,유대식 동아시아식생활학회 2001 동아시아식생활학회지 Vol.11 No.1

Since the Industrial Revolution, people have enjoyed an abundant life, owing to the technological innovations of science. However, because of changes in the environment or polution to the environment, it has brought on many chronic diseases. Especially, even though it may be a small amount, if cadmium gets into a human body, because its biological half life is long, it fatally causes a kidney disease and damage to human organisms. It was reported that Metallothioneins(MT), a substance that is closely related with a free radical that comes from environmental pollution and the course of which cadmium, which causes chronic addiction in the body, is formed, along with harmful metals, make the toxicity reduce. MT compound led into the body by cadmium indirectly functions as an antioxidation, supplied adequate amount of vitamin E. and suppresses the accumulation of cadmium in heart, liver and blood. Cadmium content found in Korean soil according to the test conducted from 1992 to 1996 was 0.02~0,03㎎/㎏ in cereals, pulses, and potatoes. Free radical scavenger, finding solution for metal substance that comes from environmental pollution from food and natural substances implicates a better future for the study of food science.

발포성 사과주 제조에 관한 연구

정기택,유대식 경북대학교 1971 生産技術 Vol.5 No.-

We experimented about the selection of strains, adding sugar and materials for increasing a foam-retention, as a basis study to brew a sparkling apple wine. The results are such as following. a) B-1 strain was selected and fixed as a suitable yeast to a fermentation in low temperature. b) B-1 strain had a fermentation form that was very slowly at first time and was very fast as the time goes. c) The concentration of optimum alcohol was 12%, also 6% is possible. d) Sucrose was better than glucose as adding sugar for the after fermentation, and its adding quantity was 4% and good. e) Malt extract solution was considered to be most effective as an increasing materials for a foam-retention, and its adding quautity was 50% best and 20% good.

液體麴製造에 關한 硏究 : 異種菌株의 混合培養時 麴菌 移植方法에 關하여 Studies on inoculating method, cultivating different organisms of Aspergillus genus in the same medium

鄭基澤,兪大植 慶北大學校 1968 論文集 Vol.12 No.-

Mechanism of Cadmium Accumulation into Cell of Cadmium - Ion Tolerant Yeast

Yu, Tae Shick,Song, Hyung Ik,Chung, Ki Taek 한국산업미생물학회 1990 한국미생물·생명공학회지 Vol.18 No.3

본 논문은 카드뮴 내성 효모, Hansenula anomala B-7에 있어서 카드뮴의 세포내 축적의 기작에 대하여 연구했다. 생물학적 활성을 상실시킨 scalded cells은 living cells보다 2∼3배량의 카드뮴을 uptake 하였다. Living cells은 uptake한 카드뮴의 74%를 세포외층에 흡착시켰으며, 26%의 카드뮴은 세포내에 축적되었다. 그러나 scalded cells에서는 98.3%의 카드뮴을 세포외층에 흡착시켰으며, 1.7%의 카드뮴만을 세포내에 축적시켰다. Living cells은 Triton X-100에 의하여 카드뮴의 uptake와 축적이 162.3%와 275.4%씩 촉진되었으나, scalded cells은 아무런 영향을 받지 않았다. 더욱이 living cells은 카드뮴의 uptake와 축적이 대사저해제인 2,4-dinitrophenol, sodium azide 및 potassium cyanide에 의하여 강하게 저해되었으나, scalded cells에 있어서 카드뮴의 uptake는 아무런 영향을 받지 않았다. 이상의 결과로 카드뮴 내성 효모에 의한 카드뮴의 세포내 축적은 생물학적 활성에 의하여 이루어지며, 특히 전자전달계의 저해제인 sodium azide에 의하여 카드뮴의 축적이 강하게 저해되므로 에너지 의존성임을 시사했다. The mechanism of intracellular accumulation of cadmium in a cadmium-ion tolerant yeast, Hansenula anomala B-7, which is an extreme cadmium tolerant strain and has the ability to take up a large amount of cadmium was investigated. The amounts of cadmium taken up by the scalded yeast cells were 2 to 3 times more than the value of the living cells. The living Hansenula anomala B-7 cells adsorbed 74% of cadmium taken up onto the other layer of the cells and 26% of it accumulated inside the cells. But the scalded cells adsorbed 98.3% of cadmium taken up and accumulated 1.7% of it inside the cells. A cadmium uptake and its accumulation were accelerated up to 162.3% and 275.4% by Triton X-100 in the living cells, respectively. Whereas in the scalded cell cadmium uptake was not affected by Triton X-100. Furthermore the cadmium uptake and its accumulation were strongly inhibited by metabolic inhibitors like 2,4-dinitrophenol, sodium azide and potassium cyanide in the living cells, but in the scalded cells cadmium uptake was not affected by metabolic inhibitors. These results suggested that the intracellular accumulation of cadmium by the cadmium-tolerant Hansenula anomala B-7 cells was apparently dependent of biological activity, and also gave evidence of the existance of energy-dependent system.

Purification and Characteristics of Glucoamylase in Aspergillus oryzae NR 3-6 Isolated from Traditional Korean Nuruk

Yu, Tae-Shick,Kim, Tae-Hyoung,Joo, Chong-Yoon The Microbiological Society of Korea 1999 The journal of microbiology Vol.37 No.2

The purification system of glucoamylase (glucan 1,4-${\alpha}$-glucosidase, EC 3. 2. 1. 3), some characteristics of the purified enzyme and hydrolysis rate of various raw starch were investigated through several experiments. The enzyme was produced on a solid, uncooked wheat bran medium of Aspergillus oryzae NR 3-6 isolated from traditional Korean Nuruk. The enzyme was homogeneously purified 6.8-fold with an overall yield of 28.3% by the criteria of disc- and SDS-polyacrylamide gel electrophoresis. The molecular weight was estimated to be 48 kDa by SDS-PAGE. The optimum temperature and pH were 55$^{\circ}C$ and 4.0, respectively. The enzyme was stable at a pH range of 3.0∼10.0 and below 45$^{\circ}C$. Enzyme activity was inhibited about 27% by 1mM Hg2+. The hydrolysis rate of raw wheat starch was shown to be 17.5-fold faster than the hydrolysis rate of soluble starch. The purified enzyme was identified as glucoamylase because the product of soluble starch by the purified enzyme was mainly glucose by thin layer chromatography.

Chemical Modification of Intracellular Cytosine Deaminase from Chromobacterium violaceum YK 391

Tae Shick Yu,김정,김대현 한국생물공학회 2005 Biotechnology and Bioprocess Engineering Vol.10 No.3

Cytosine deaminase (cytosine aminohydrolase, EC 3.5.4.1) stoichiometrically catalyzes the hydrolytic deamination of cytosine and 5-fluorocytosine to uracil and 5-fluorouracil, respectively. Amino acid residues located in or near the active sites of the intracellular cytosine deaminase from Chromobacterium violaceum YK 391 were identified by chemical modification studies. The enzymic activity was completely inhibited by chemical modifiers, such as 1 mM NBS, chloramine-T, -CMB, -HMB and iodine, and was strongly inhibited by 1 mM PMSF and pyridoxal 5'-phosphate. This chemical deactivation of the enzymic activity was reversed by a high concentration of cytosine. Furthermore, the deactivation of the enzymic activity by -CMB was also reversed by 1 mM cysteine-HCl, DTT and 2-mercaptoethanol. These results suggested that cysteine, tryptophan and methionine residues might be located in or near the active sites of the enzyme, while serine and lysine were indirectly involved in the enzymic activity. The intracellular cytosine deaminase from C. violaceum YK 391 was assumed to be a thiol enzyme.

Effect of Titanium-Ion on the Growth of Various Bacterial Species

Tae Shick Yu 한국미생물학회 2004 The journal of microbiology Vol.42 No.1

There are a number of studies that explain the metabolism and roles of metallic titanium and titaniumion. One of the most intriguing results from these studies is the finding of metallic titanium having no bacteriostatic effects on oral bacterial species. In this research, the effects of titanium-ion on the growth of twenty-two bacterial species, some of which are commonly found in foods such as yoghurt, kimchi, and soy fermented products, were investigated. All but two bacteria, Escherichia coli and Pseudomonas aeruginosa appeared to be sensitive to titanium-ion. These two species were grown on 360 μg/ml of titanium-ions, and they were found to be resistant to the titanium-ion. Both the wild-type and plasmid- cured E. coli showed good growth in a medium with 200 μg/ml of titanium-ions. These results suggest that titanium-resistance was independent from the effects of the plasmid in E. coli.

Nutritional and Cultural Characteristics of Cytosine Deaminase from Pseudomonas auerofaciens

Yu Tae-Shick 啓明大學校 生活科學硏究所 1976 科學論集 Vol.3 No.-

Optimization of Culture Conditions for the Production of Pyrimidine Nucleotide N-Ribosidase from Pseudomonas oleovorans

Yu, Tae-Shick Korean Society of Life Science 2004 생명과학회지 Vol.14 No.4

Pyrimidine nucleotide N-ribosidase (pyrimidine 5'-nucleotide phosphoribo (deoxyribo) hydrolase/pyrimidine 5'-nucleoude nucleosidase, EC 3.2.2.10) directly catalyzes pyrimidine 5'-nucleotide to pyrimidine base and ribose (deoxyribo) 5-phosphate. In order to clarify the best nutritional conditions for the growth and the pyrimidine nucleotide N-ribosidase production of Pseudomonas oleovorans ATCC 8062 the effects of various nutrients such as different carbon and nitrogen sources were studied. For the both the growth and the enzyme production, 2% fumarate, 1.5% peptone, 5% corn steep liquor (CSL) and 1% ammonium chloride were excellent carbon and nitrogen sources, respectively. Optimum pH, temperature, and cultivation time for the enzyme production were 7.0, $28^{\circ}C$, and 48 h, respectively. The pyrimidine nucleotide N-ribosidase of P. oleovorans ATCC 8062 was not induced by UMP and its derivatives, and was constitutive enzyme. Pyrimidine nucleoade N-ribosidase (pyrimidine 5'-nucleotide phosphoribo (deoxyribo) hydrolase/ pyrimidine 5'-nucleotide nucleosidase, EC 3.2.2.10)는 CMP와 UMP를 직접 분해하여 cytosine과 uracil를 생성하는 가수분해효소이다. 본 연구에서는 Pseudomonas oleovorans ATCC 8062의 생육과 pyrimidine nu-cleotide N-ribosidase생성에 미치는 탄소원과 질소원의 영향 및 생육인자 등에 대하여 검토했다. 효소생성의 최적배양조건은 2% fumarate, 1.5% peptone, 5% corn steep liquor (CSL)과 1% ammonium chloride의 배지조성(초기 pH 7.0)으로 $28^{\circ}C$, 48시간 진탕 배양이 양호했다. 효소의 활성은 생육이 최대에 도달하는 정지기 후기에 최대에 도달하며, 그 이후부터 급속히 불활성화 되었다. P. oleovorans의 pyrimidine nucleocde N-ribosidase는 UMP에 의하여 유도 생성되지 않으므로 구성효소이며, 내생효소였다.