Characteristics of an Imperfect Fungus, Microsporum Glaucus Yeeh sp. nov.

Jung, Kwan Yil,Yeeh, Yeehn 인제대학교 1988 仁濟醫學 Vol.9 No.2

토양으로부터 dermatophyte로 인정되는 불완전 곰팡이를 분리하여 그 형태학적 및 생리학적 특성 등을 관찰하고 검토하였다. 그 결과로서 분리된 곰팡이는 Microsporum 속의 한 species로 사료되었다. 또한 이 불완전한 곰팡이를 이미 보고된 바 있는 Microsporum 속의 여러 species와 비교한 결과 colony의 색깔, macroconidium의 형태 또는 세포 수 통과 관련해서 관련종과 다른 육안적 및 현미경적인 특징을 나타내었다. 이 불완전 곰팡이는 Microsporum 속의 여러 species 가운데 아직 보고된 바 없는 새로운 species로 생각되었으며, 더욱 이 곰팡이는 본 연구자가 분리한 Microsporum nigricans Yeeh sp. nov.와는 colony의 색깔 및 macroconidium의 평균 수에 있어서 차이가 있었다. 그러므로 이 곰팡이의 현미경적 및 생리학적 특성과 특히 육안적으로 회색이었으므로 이 곰팡이를 Microsporum glaucus Yeeh sp. nov.로 이름 붙이고 이 후 그렇게 부를 것을 제안한다. An imperfect fungus recognized as a dermatophyte was isolated from soil samples and the macroscopic, microscopic and physiological properties of this isolate were observed and tested. The results showed that this fungus belonged to a species within genus Microsporum. From comparisons of this fungus with the known species within genus Microsporum, she presented many different characteristics from the related species, including colony color, and shape, or number in a cell of macroconidium. This isolate was considered to be a novel species in genus Microsporum. In addition, this fungus differed much in the colony color and mean number of macroconidium from Microsporum nigricans Yeeh sp. nov isolated and named by this author. Therefore, this author proposes to name her Microsporum glaucus Yeeh sp. nov. because of some characteristics from microscopic and physiological results and especially because of the light blackish gray color from the macroscopic observations.

불완전 진균 Microsporum nigricans Yeeh sp.nov의 특성

이인,Yeeh, Yeehn The Microbiological Society of Korea 1985 미생물학회지 Vol.23 No.4

토양으로부터 dermatophyte로 인정되는 불완전 곰팡이를 분리한 후 그 형태학적 및 생리학적 특성등을 검토하여 이미 알려진 종과 비교한 결과 분리주는 Microsporum속에 속하였으나 colony의 색깔, macroconidium의 형태 또는 세포수 등과 관련하여 관련종인 Microsporum gypseum 및 Microsporum nanum과 비교해서 육안적.현미경적인 다른 특징을 나타내었다. 이 분리주는 Microsporum 속의 아직 보고된 바 없는 새로운 종으로 사료되었으며 육안적으로 진한 흑색을 나타내었으므로 Microsporum nigricans Yeeh sp. nov.로 이름붙였다. An imperfect fungus recognized as a dermatophyte was isolated from soil samples and the macroscopic, microscopic and physiological characteristics were examined. From the comparisons of this isolate with the known species, the strain belonged to the genus Microsporum. She showed mant different characteristics from the related species, including colony color and shape, or number in a cell of macrocondium. This isolate was considered to be a novel species in the genus Microsporum. Therefore the name was given to her as Microsporum nigricans Yeeh sp. nov. because of dark blackish color from the macroscopic observation.

분리된 미생물의 Cytosine, Uracil 및 5-Fluorocytosine의 동화 능력과 Nocardia sp.240 의 특성

최하진,이인,박경식 인제대학교 1987 仁濟醫學 Vol.8 No.2

토양 및 자연으로부터 분리한 미생물 가운데 cytosine을 동화할 수 있는 세균(9종), 효모(7종), 진균(5종) 및 방선균(3종) 등을 동정한 후 이들을 대상으로 pyrimidine 유도체 가운데 uracil 및 5-fluorocytosine(5-FC)에 대한 동화 능력을 검토하였다. 그 결과 이들 세 기질을 동시에 동화하는 세균은 Corynebacterium ulcerans Y-1, Acinetobacter calcoaceticus 13 및 Arthrobacter simplex JH-13 등이었고, 효모는 Candida diffluens 111균주, 진균으로는 Microsporun nigricans Yeeh sp. nov.와 M. glaucus Yeeh sp. nov.로 나타났으며 방선균으로는 Nocardia sp. 240균주만이 동시의 동화능을 가진 것으로 나타났다. 한편 이들 세 기질을 동시에 동화하는 미생물 가운데 분리균주인 방선균 240을 동정하기 위해 형태적, 배양적 및 생리학적 성질을 검토한 결과 hypae에 격막이 있고 생식이 fragmentation에 의해 일어나며, tyrosine agar 등에서 soluble pigment를 생성하고, 기균사가 glucose agar를 비롯한 synthetic glycerol agar 등에서 나타났다. 또한 Gram 양성, gelatin 액화 양성, MacConkey agar에서의 비증식, nitrate 비환원능, 세포벽 아미노산 성분이 L, L-diaminopimelic acid 함유 등의 특성을 고려해서 검토 결과 Nocardia에 속하는 방선균으로 사료되었으며 Nocardia sp.240으로 명명하였다. From the cytosine-assimilating bacteria(9), yeasts(7), molds(5) and actinomycetes(3) isolated from soil, or natural habitat samples, the capability of uracil and 5-fluorocytosine between pyrimidines was examined. The results of examinations indicated that these three substrate-assimilating strains were Corynebacterium ulcerans Y-1, Acinetobacter calcoaceticus 13 and Arthrobacter simplex JH-13 as bacteria, Candida diffuens 111 only as yeast, Microsporum nigricans Yeeh sp. gov. and Microsporum glaucus Yeeh sp. nov. as molds, and Nocardia sp. 240 as actinomycete. Of the three-assimilating microorganisms isolated, the morphological, cultural and physiological properties of an actinomycete 240 strain were also discussed. The strain had hypae with septum and her reproductive body seemed to be mycelial fragments formed from aerial hypae. This isolate produced soluble pigments on tyrosine agar, oat meal agar and milk agar, and also formed aerial mycelium on synthetic glycerol agar, including glucose agar. And she showed positive result in Gram reaction and gelatin liquefaction, but did negative one in growth on Mac Conked agar and in nitrate reduction. The amino acid analysis of cell wall of this isolate presented positive result in the content of L, L-diaminopimelic acid. From the above comprehensive properties, this strain was considered to be genus Nocardia among actinomycetes. Therefore the name was given to the isolate as Nocardia sp.240.

Production of 5-flourouracil by an Extracellular Cytosine Deaminase and Its Enzymic Characteristics

Yeeh, Yeehn 인제대학교 1986 仁濟醫學 Vol.7 No.2

Corynebacterium sp.Y-1균주로부터 생성된 세포의 cytosine deaminase의 성질을 27∼80% 유안 분획 후에 검토하였다. 그 결과 이 효소는 그 기질로서 cytosine, 5-fluorocytosine 및 5-methylcytosine을 각각 uracil, 5-fluo-rouracil 및 thymine으로의 전환을 촉매할 수 있는 능력을 가진 것으로 판명되었다. 또한 이 효소는 50℃ 이하에서는 대체로 안정하였으나 50℃ 이상에서는 점차 안정성이 감소하였고 70℃ 부근에서는 완전히 불활성화하였다. 한편 이 효소의 안정성의 유지에는 tris-HC1 완충액이 potassium phosphate 완충액보다 효과적이었으며 최대 활성을 나타내는 pH는 8.0에서 8.5의 범위로 나타났다. 금속 이온에 대한 효소 활성을 검토한 결과로서 1mM의 Co2+, Fe3+, K+, Mg2+, Mn2+, 및 Na+ 등은 다소 활성을 증가시켰으나 Ag+, Hg2+, Pb2+ 및 Zn2+ 등에 대해서는 완전히, 혹은 거의 완전하게 불활성화하였다. 또 이 효소는 p-chloromercuric benzoate, N-ethylmaleimide 및 trichloroacetic acid등과 같은 전형적인 효소저해제의 존재하에서는 그 활성이 완전히 저해되었고 0.1mM의 I2, 2-mercaptoethanol, NaCN, NaF, 2, 21-dipyridyl 및 EDTA 등에 의해 강력하게 저해를 받는 것으로 나타났다. 따라서 이 세포의 cytosine deaminase는 현재까지 보고된 바 있는 세포내 및 세포의 효소와는 다소 그 성질이 다른 것으로 추정되었다. Some properties of an extracellular cytosine deaminase excreted from Corynebacterium sp. Y-1 strain were examined after 20-80% ammonium sulfate fractionation. This enzyme possessed the capability to catalyze the conversion of cytosine, 5-fluorocytosine, or 5-methylcytosine to uracil, 5-fluorouracil, or thymine as substrate, respectively. The enzyme was at large stable below 50℃, but the stability was progressively decreased from above 55℃ and completely inactivated at around 70℃. Tris-HCl buffer seemed to be more effective than potassium phosphate buffer in the stability of this enzyme. And this enzyme showed the range of 8.0 to 8.5 in pHs for the maximum activity. and was considered to be thermostable. The presence of 1 mM of Co2+, Fe3+, K+, Mg2+, Mn2+, and Na+ increased more or less the enzyme activity, but the presence of Ag+, Hg2+, Pb2+, and Zn2+ in reaction mixture resulted in the complete, or nearly complete inactivation of the enzyme activity. This enzyme was completely inhibited in the presence of p-chloromercuric benzoate, N-ethylmaleimide and trichloroacetic acid as the typical enzyme inhibitors and also strongly inhibited in the presence of 0.1 mM of I2, 2-mercaptoethanol, NaCN, NaF, 2, 2'-dipyridyl and ethylenediaminetetraacetic acid. Accordingly this enzyme was assumed more or less different from the other endocellular, or extracellular enzymes reported so far.

Distribution of Algae from the Suyong-sewer and their Taxonomical Positions

Yeeh, Yeehn 인제대학교 1985 仁濟論叢 Vol.1 No.2

수영천에 출현하는 조류의 분포상과 분류학적 위치 A taxonomical investigation on aquatic algae, especially diatoms from the Suyong-sewer water was performed for 9 months from April to October, 1984. The algae collected from this sewer were indentified and classified. The algae indentified were classified into 1 phylum, 1 class, 2 subclasses, 4 orders, 8 families and 26 species in total

Growth Characteristics of Candida sp. JY-5 in Ethanol, or Acetic Acid Substrate as Sole Source of Carbon by Continuous Culture

Yeeh, Yeehn 인제대학교 1986 仁濟醫學 Vol.7 No.4

Ethanol, acetic acid acid 및 acetaldehyde 동화균주인 Candida sp. JY-5를 ethanol 및 acetic acid 기질에서 연속배양하여 그 증식특성을 검토하였다. 그 결과 증식수율과 조단백질함량은 희석율의 증가에 따라 증가하였으며 이 현상은 한계희석율까지 계속하였다. 1.0% ethanol 공급농도에서 한계희석율은 약 0.5hr-1이었으며 증식수율은 약 70.4%이었고 조단백질 함량은 약 53.0%로 나타났다. 한편 acetic acid 공급기질의 경우, 1.0%의 공급농도에서 Candida sp. JY-5 균주는 한계희석율이 약 0.4hr-1이었고 증식수율은 약 55.2%, 조단백질 함량은 약 54.5%로 나타났다. The continuous culture of ethanol-, acetic acid-, and acetaldehyde-assimilating yeast, Candida sp. JY-5 was conducted in ethanol, or acetic acid medium as sole source of carbon. The cell yield and content of crude protein were slightly increased with the dilution rate up to the practical dilution rate (Dp. hr-1). At 1.0% of the constant feed concentration of ethanol, the Dp was about 0.5 hr-1 in this strain. the cell yield and the content of crude protein was approximately 70.4 and 53.0%, respectively. At 1.0% of the constant feed concentration of acetic acid, the cell of Candida sp. JY-5 showed approximately 0.4 hr-1 in the Dp, approximately 55.2% in cell yield, and approximately 54.5% in the content of crude protein.

Isolation of an Ethanol-, Acetic acid-, and Acetaldehyde-assimilationg Yeast and the Growth Patterns on These Three-carbon Compounds

Yeeh, Yeehn 인제대학교 1987 仁濟醫學 Vol.8 No.1

C2화합물 가운데 ethanol, acetic acid 및 acetaldehyde을 공통적으로 동화할 수 있는 효모를 분리한 후 형태학적, 배양적 및 생리학적 특성을 고려하여 그 분류학적 위치를 검토하였다. 그 결과 분리 효모는 다극 출아법에 의한 영양 증식을 하였으며 자낭포자를 형성하지 않고 또한 색소가 형성되지 않는 점으로 보아 Candide속에 속하였으며 Candida sp. Y-5로 명명하였다. 이 분리균주의 세포 증식에 대한각종 화합물의 영향을 검토한 결과 무기질소원으로 ammonium sulfate, ammonium phosphate monobasic 혹은 dibasic 등에서 그 증식효과가 양호하였고 유기질소원으로서 peptone 및 yeast extract가 가장 좋은 결과를 나타내었다. Vitamin류의 경우 folic acid, nicotinic acid, pyridoxine-HCl 및 thiamine-HCl을 비롯해서 biotin등이 촉진인자로 작용하였으며 금속화합물 가운데 FeSO4, CaCl2 · 2H2O, MgSO4 · 7H2O, BaCl2, Ba2B4O7, · 10H2O, KCl 및 NaCl 등은 증식 촉진인자로 평가되었다. 당류로서는 Maltose가 수율을 크게 증가시켰으나sorbose나 lactose는 수율이 특히 약하였다. 유기산 가운데 acetate에서 최대수율이 나타났고 formic acid는 저해하였다. 한편 alcohol류 중에는 ethanol 만이 증식 효과가 컸고 그 외의 대부분은 저해인자로 작용 하였다. 이 외에 pyrogallol, hydroquinone, sodium benzoate 및 salicylic acid 등은 이 균주의 세포증식을 완전히 저해하였다. 또한 ethanol, acetic acid 및 acetaldehyde를 단일 탄소원으로 하여 Candida sp. Y-5효모의 증식 특성 을 batch culture를 통해 검토하였다. Ethanol상에서 이 효모의 지수적 증식기 동안의 비증식도(μ) 값은 농도가 0.5g/l 이상일 경우 그 초기 농도에 따라 변화하나 비례하지는 않았다. 최대 비증식도는 0.274hr-1이었고 최대 증식수율은 10g/l 농도에서 55.2%이었다. Acetic acid상에서의 비증식도는 이 기질의 초기 농도에 관계없이 일정하였으며 그 값이 0.12hr-1, 최대 증식수율은 10g/l 농도에서 42.3%로 나타났다. 한편 acetaldehyde 기질에서의 지수적 증식기 동안의 최대 비증식도는 0.057hr-1이었고 최대 증식 수율은 0.2g/l 농도에서 45.0%였다. 한편 이 균주를 ethanol 및 acetic acid 기질에서 연속 배양하여 그 증식 특성을 검토한 결과 증식수율과 조단백질 함량은 희석율의 증가에 따라 증가하였으며 이 현상은 한계희석율까지 계속하였다. 1.0% ethanol 공급농도에서 한계희석율은 약 0.5hr-1이었으며 증식수율은 약 65%이었고 조단백질 함량은 약 50%로 나타났다. 한편 acetic acid 공급기질의 경우, 1.0%의 공급 농도에서 Candida sp.Y-5 균주의 한계희석율이 약 0.4hr-1이었고 증식수율은 약 36%, 조단백질 함량은 약 50%로 나타났다. An yeast assimilating ethanol, acetic acid and acetaldehyde among C2-compounds was isolated. The morphological, cultural, physiological and biochemical properties of the isolate were examined. As the results of taxonomical researches, the isolate was identificed as the genus Candida and named as Candida sp. Y-5. The effects of various compounds as sole source of carbon were examined on the cell growth from the isolated strain, Candida sp Y-5. Ammonium sulfate, ammonium phosphate monobasic, or bibasic as inorganic nitrogen source showed good growth and the highest growth was obtained from peptone and yeast extract as organic nitrogen source in this strain. As the effects of vitamins, biotin, including pantothenate, folic acid, nicotinic acid, pyridoxine-HCI, ribortlavin and thiamine-HCI in this strain acted as the growth-stimulating factors. Among metal compounds, the growth-stimulating effects were displayed on FeSO4, CaCl2 · 2H2O, MgSO4 · 7H2O, BaCl2, Ba2B4O7, · 10H2O, KCl and NaCl. The growth yield from maltose among sugars was high but that from sorbose and lactose was scarce. Acetic acid and among organic acids showed the highest yield, but formic acid was shown as an inhibitory compound for this strain. Ethanol as alcohols exhibited the high yield of cells, but most of alcohols employed acted as the inhibitory compounds. And pyrogallol, hydroquinone, sodium ben-zoate and salicylic acid presented the completely inhibitory effects on the cell growth of this strain. The growth characteristics of Candida sp. Y-5 were examined on ethanol, acetic acid, or acetaldehyde as sole source of carbon by batch culture. The specific growth rates (μ) of this strain on an ethanol during the exponential period were changed depending upon the initial concentrations at above 0.5g/l, but not in the proportion. The highest μ value was 0.27hr-1 and the maximum growth yield was 55.2% at the concentration of 10g/l. The μ values on an acetic acid substrate were constant regardless of the initial concentrations presenting 0.12 hr-1 in the highest value. The maximum growth yield was shown as 42.3% at the initial concentration of 10g/l. The highest μ value on an acetaldehyde during the exponential period was 0.057 hr-1 and the maximum growth yield was 45.0% at the initial acetaldehyde concentration of 0.2g/l. The continuous culture of ethanol, acetic acid, and acetaldenhyde-assimilating yeast. Candida sp. Y-5 was conducted in ethanol, or acetic acid medium as stole source of carbon. The cell yield and content of crude protein were slightly increased with the dilution rate up to the practical dilution rate (Dp. hr-1). At 1.0% of the constant feed concentration of ethanol, the Dp was about 0.5hr-1 in this strain, the cell yield and the content of crude protein was approximately 65 and 50%, respectively. At 1.0% of the constant feed concentration of acetic acid, the cell of Candida sp. JY-5 showed approximately 0.4hr-1 in the Dp, approximately 36% in cell yield, and approximately 50% in the content of crude protein.

The Conversion of 5-Fluorocytosine to 5-Fluorouracil by and Exogenous Bacterial Enzyme

Yeeh, Yeehn 인제대학교 1985 仁濟醫學 Vol.6 No.3

5-Fluorocytosine에 특이성을 가짐으로서 항종양제인 5-Fluorouracil로 전환시킬 수 있는 세포 외 효소를 생산하는 세균을 토양에서 분리한 후 그 분류학적 위치를 검토하였다. 그 결과 분리균은 Corynebacterium ulcerans와 유사하였으며 Corynebacterium Y-1로 이름 붙였다. 세포 외 5-Fluorocytosine deaminase의 생성을 위한 배지의 최적 조성은 Glucerin 0.5%, Peptone 1.0%, Yeast extract 0.5% 및 NaCl 0.5%(pH 7.0%)이었으며 30℃에서 경시적으로 배양한 결과 효소 생산은 배양 후 30시간 부근에서 최대로 나타났다. A microorganism producing an exogenous 5-fluorocytosine deaminase catalyzing the conversion of 5-fluorocytosine to 5-fluorouracil was isolated from soil samples. As the results of the taxonomical researches, some properties of the isolate appeared to be generally identical to those of Corynebacterium ulcerans, and the auther named her as Corynebacterium Y-1. The production of the particular enzyme under the optimum conditions followed by the composition of 0.5% glycerin, 1.0% of peptone, 0.5% of yeast extract and 0.5% of sodium chloride (pH 7.0) reached the maximum value at around 30 hours after aerobic cultivation.

Effects of Various Compounds as Sole Sources of Carbon on the Cell Growth of Candida sp. JY-5

Yeeh, Yeehn 인제대학교 1986 仁濟醫學 Vol.7 No.4

분리균주인 Candida sp. JY-5의 세포증식에 대한 각종 화합물의 영향을 검토한 결과 무기질소원으로 ammonium sulfate, ammonium phosphatd monobasic 혹은 dibasic 등에서 그 증식효과가 양호하였고 유기질소원으로서 peptone 및 yeast extract가 가장 좋은 결과를 나타내었다. Vitamin류의 경우 folic acid, nicotinic acid, pyridoxine-HCl 및 thiamine-HCl을 비롯해서 biotin 등이 촉진인자로 작용하였으며 inositol은 저해인자로 보였다. 금속화합물 가운데 FeSO4, CaCl2ㆍ2H2O, MgSO4ㆍ7H2O, BaCl2, Ba2B4O7ㆍ10H2O, KCl 및 NaCl 등은 증식촉진인자로 평가되었으나 AgNO3, HgCl2 and NiSO4ㆍ7H2O 등은 완전한 저해효과를 나타내었다. 당류로서는 Maltose가 수율을 크게 증가시켰으나 sorbose나 lactose는 수율이 특히 약하였다. 유기산 가운데 acetate에서 최대수율이 나타났고 formic acid는 저해하였다. 한편 alcohol류 중에는 ethanol만이 증식효과가 컸고 그 외의 대부분은 저해인자로 작용하였다. 이 외에 pyrogallol, hydroquinone, sodium benzoate 및 salicylic acid등은 이 균주의 세포 증식을 완전히 저해하였다. The effects of various compounds as sole source of carbon were examined on the cell growth from the isolated strain, Candida sp. JY-5. Ammonium sulfate, ammonium phosphate monobasic, or dibasic as inorganic nitrogen source showed good growth and the highest growth was obtained from peptone and yeast extract 35 organic nitrogen source in this strain, As the effects of vitamins, biotin, including pantothenate, folic acid, nicotinic acid, pyridoxineㆍHCl, riboflavin and thiamineㆍHCl in this strain acted as the growth- stimulating factors, but the inhibition of growth was shown on inositol. Among metal compounds, the growth-stimulating effects were displayed on FeSO4, CaCl2ㆍ2H2O, MgSO4ㆍ7H2O, BaCl2, Ba2B4O7ㆍ10H2O, KCl and NaCl, but the growth-inhibitory effects were on AgNO3, HgCl2 and NiSO4ㆍ7H2O. The growth yield from maltose among sugars was high but that from sorbose and lactose was scarce. Acetic acid among organic acids showed the highest yield, but formic acid was shown as an inhibitory compound for this strain. Ethanol as alcohols exhibited the high yield of cells, but most of alcohols employed acted as the inhibitory compounds. And pyrogallol, hydroquinone, sodium benzoate and salicylic acid presented the completely inhibitory effects on the cell growth of this strain.

Properties of an Extracellular 5-Fluorocytosine Deaminase

Yeeh, Yeehn,Jun, Hong Ki,Yoon, Yong Kyun 한국산업미생물학회 1992 한국미생물·생명공학회지 Vol.20 No.2

토양 분리균주로부터 얻은 배양액을 20∼80% 황산 암모늄으로 분획한 후 세포외 cytosine deaminase의 성질을 검토하였다. 이 효소는 cytosine과 5-fluorocytosine(5-FC)에 기질 특이성을 가짐으로서 각각 uracil과 5-fluorouracil(5-FU)로의 전환을 촉매하였다. 효소안정성에 대한 온도와 보존시간을 tris-HCl 완충 용액에서 검토한 결과 최적온도는 50℃ 부근이하에서 90% 이상의 잔존활성을, 보존시간은 4일정도에서 80% 이상의 잔존활성을 유지하였다. 최대활성은 pH 8.0과 37℃의 온도에서 나타났다. 활성에 적당한 pH는 8.O∼8.5였고 온도는 37∼45℃의 범위였다. 한편 이 효소는 Ag^+, Hg^2+, Zn^2+, Cu^2+, Sn^2+와 Pb^2+ 등의 금속이온이 존재하면 그 활성이 강력하게 저해 되었으며, K^+, Fe^3+, Mg^2+, 또는 Na^+ 등은 효소활성을 다소 증가시키는 것으로 보였다. 또한 이 효소는 1 mM의 EDTA, NaCN, 또는 pentachlorophenol 등과 같은 검증된 대부분의 효소저해제에 의해 그 활성이 상당한 영향을 받았으며, 특히, 1mM과 10mM의 p-CMB와 TCA 등에는 완전한 불활성화를 보였다. Some properties of an extracellular cytosine deaminase excreted from an isolate from soil samples were examined after 20∼80% ammonium sulfate fractionation. The enzyme catalyzed the conversion of cytosine and 5-fluorocytosine into uracil and 5-fluorouracil by substrate specificity, respectively. The optimum temperature and storage time on the stability of the enzyme preparation were below 50℃ keeping above 90% of the residual activity and near 4 days keeping above 80% of the residual one in Tris-HCl buffer. The maximum activity was also obtained at 8.0 in pH and 37℃ in temperature. The pHs and temperatures for enzyme activity ranged from 8.O∼8.5 and from 37∼45℃, respectively. The presence of Ag^+, Hg^2+, Zn^2+, Cu^2+, Sn^2+, or Pb^2+ in the reaction mixture resulted in the marked inhibition in enzyme activity, but 1 mM of K^+, Fe^3+, Mg^2+ or Na^+ slightly increased the activity. The enzyme preparation was heavily affected by most of inhibitors tested such as 1 mM of EDTA, NaCN and pentachlorophenol, and completely inactivated by p-CMB and TCA of 1 mM, or 10 mM.