Bacillus brevis CD162 Cyclodextrin Glycosyltransferase의 정제 및 특성

김명희,임영희,오태광,손천배,Kim, Myung-Hee,Lim, Young-Hee,Oh, Tae-Kwang,Sohn, Cheon-Bae 한국응용생명화학회 1997 Applied Biological Chemistry (Appl Biol Chem) Vol.44 No.4

The cyclodextrin glycosyltransferase (CGTase, EC 3.2.1.19) from Bacillus brevis CD162 was purified by precipitating with ammonium sulfate, DEAE-Sepharose CL-6B column chromatography and Sephadex G-150 column chromatography. The molecular mass and pI of the purified enzyme were estimated to be 74,000 and 6.3 by SDS-PAGE and isoelectric focusing, respectively. The purified enzyme was clearly identified as the CGTase by zymogram after SDS-PAGE. The optimum pH and temperature for the enzyme activity were 8.0 and $55^{\circ}C$, respectively. The enzyme was stable at the range of pH $5.5{\sim}9.0$, and up to $50^{\circ}C$. The amino acid sequence from the $NH_2-terminal$ of the purified CGTase was Ser-Val-Thr-Asn-Lys-Val-Asn-Tyr-Ser-Lys-Asp-Val-Ile-Tyr-Gln. The yields of the products from starch as the substrate were 1.3% for ${\alpha}-$, 33.9% for ${\beta}-$, and 9.7% for ${\gamma}-cyclodextrin$. Bacillus brevis CD162가 생산하는 cyclodextrin glycosyltransferase (CGTase)를 ammonium sulfate 침전, DEAE-Sephadex CL-6B 및 Sephadex G-150 컬럼 크로마토그래피를 수행하여 분리정제하였다. 정제된 CGTase는 분자량이 약 74,000, 등전점은 약 6.3인 단백질이었고, 정제된 단백질을 SDS-PAGE한 후 변성된 단백질을 재활성시켜 zymogram을 수행한 결과 cyclodextrin glycosyltransferase임을 확인할 수 있었다. 이 효소의 최적활성 pH와 온도는 각각 8.0과 $55^{\circ}C$이었으며, pH $5.5{\sim}9.0$과 $50^{\circ}C$까지 안정한 활성을 보였다. 또한, CGTase의 $NH_2$-말단 부위의 아미노산서열은 Ser-Val-Thr-Asn-Lys-Val-Asn-Tyr-Ser-Lys-Asp-Val-Ile-Tyr-Gln 이었으며, 전분으로부터 cyclodextrin으로의 전환률을 분석한 결과, ${\alpha}$-cyclodextrin은 1.3%, ${\beta}$-cyclodextrin은 33.9% ${\gamma}$-cyclodextrin은 9.7% 이었다.

Bacillus brevis CD162 Cyclodextrin Glycosyltransferase의 정제 및 특성

김명희,손천배,임영희,오태광 대전대학교 이과대학 기초과학연구소 1997 自然科學 Vol.- No.-

Bacillus brevis CD162가 생산하는 cyclodextrin glycosyltransferase (CGTase)를 ammonium sulfate 침전, DEAE-Sephadex CL-6B 및 Sephadex G-150 컬럼 크로마토그래피를 수행하여 분리정제하였다. 정제된 CGTase는 분자량이 약74.000, 등전점은 약 6.3인 단백질이었고, 정제된 단백질을 SDS-PAGE한 후 변성된 단백질을 재활성시켜 zymogram을 수행한 결과 cyclodextrin glycosyltransferase임을 확인할 수 있었다. 이 효소의 최적활성 pH와 온도는 각각 8.0과 55℃이었으며, pH 5.5~9.0과 50℃까지 안정한 활성을 보였다. 또한, CGTase의 NH₂-말단 부위의 아미노산서열은 Ser-Val-Thr-Asn-Tyr-Ser-Lys-Asp-Val-Ile-Tyr-Gln 이었으며, 전분으로부터 cyclodextrin으로의 전환률을 분석한 결과, α-cyclodextrin은 1.3%, β-cyclodextrin은 33.9%, γ-cyclodextrin은 9.7% 이었다(1997년 7월 10일 접수, 1997년 9월 25일 수리) The cyclodextrin glycosyltrasferase (CGTase, EC 3.2.1.19) from Bacillus brevis CD162 was purified by precipitating with ammonium sulfate, DEAE-Sepharose CL-6B column chromatography and Sephadex G-150 column chromatography. The molecular mass and pI of the purified enzyme were estimated to be 74,000 and 6.3 by SDS-PAGe and isoelectric focusing, respectively. The purified enzyme was clearly identified as the CGTase by zymogram after SDS-PAGE. The optimum pH and temperature for the enzyme activity were 8.0 and 55℃, respectively. The enzyme was stable at the range of pH 5.5~9.0, and up to 50℃. The amino acid sequence from the NH₂-terminal of the purified CGTase was Ser-Val-Thr-Asn-Lys-Val-Asn-Tyr-Ser-Lys-Asp-Val-Ile-Tyr-Gln. The yields of the products from starch as the substrate were 1.3% for α-,33.9% for β-, and 9.7% for γ-cyclodextrin.

Γ-Cyclodextrin Glycosyltransferase 생산균주의 분리, 동정 및 효소 생산조건

김명희,손천배,임영희,배경숙,오태광 대전대학교 이과대학 기초과학연구소 1997 自然科學 Vol.- No.-

Cyclodextrin glycosyltransferase 생산균주를 토양으로부터 분리하여 형태학적, 생화학적 그리고 균주의 세포벽 지방산 조성분석에 의해 Bacillus brevis로 동정하였고, Bacillus brevis CD162로 명명하였다. 또한 배지조성에 따른 cyclodextrin glycosyltransferase의 최적생산조건을 검토한 결과, 2.0% soluble starch, 0.75% yeast extract, 0.5% bacto peptone, 0.2% KHPO₄, 0.05% MgSO₄·7H₂O, 1.5% Na₂CO₃ (pH 10.2)의 배지 조건에서 30℃에서 96시간 배양하였을 때 가장 높은 효소생산인 0.9 unit/ml을 얻을 수 있었다.(1997년 7월 10일 접수, 1997년 11월 21일 수리) A cyclodextrin glycosyltransferase-producing bacterium was newly isolated from soil using alkaline pH medium containg 1% Na₂CO₃, The isolated strain was identified as Bacillus brevis by morphological and biochemical characteristics, and designated Bacillus brevis CD162. The strain showed the best enzyme production of 0.9 unit/ml after 96 hrs of culture at 30℃ in a medium of 2.0% soluble starch, 0.75% yeast extract, 0.5% bacto peptone, 0.2% K₂HPO₄, 0.005% MgSO₄·7H₂O and 1.5% Na₂Co₃at initial pH 10.2

${\gamma}-Cyclodextrin$ Glycosyltransferase 생산균주의 분리, 동정 및 효소 생산조건

김명희,임영희,배경숙,오태광,손천배,Kim, Myung-Hee,Lim, Young-Hee,Bae, Kyung-Sook,Oh, Tae-Kwang,Sohn, Cheon-Bae 한국응용생명화학회 1997 Applied Biological Chemistry (Appl Biol Chem) Vol.44 No.4

A cyclodextrin glycosyltransferase-producing bacterium was newly isolated from soil using alkaline pH medium containing 1% $Na_2CO_3$. The isolated strain was identified as Bacillus brevis by morphological and biochemical characteristics, and fatty acid composition and designated Bacillus brevis CD162. The strain showed the best enzyme production of 0.9 unit/ml after 96 hrs of culture at $30^{\circ}C$ in a medium of 2.0% soluble starch, 0.75% yeast extract, 0.5% bacto peptone, 0.2% $K_2HPO_4$ 0.05% $MgSO_4{\cdot}7H_2O$, and 1.5% $Na_2CO_3$ at initial pH 10.2. Cyclodextrin glycosyltransferase 생산균주를 토양으로부터 분리하여 형태학적, 생화학적 그리고 균주의 세포벽 지방산 조성분석에 의해 Bacillus brevis로 동정하였고, Bacillus brevis CD162로 명명하였다. 또한 배지조성에 따른 cyclodextrin glycosyltransferase의 최적생산조건을 검토한 결과, 2.0% soluble starch, 0.75% yeast extract, 0.5% bacto peptone, 0.2% $K_2HPO_4$, 0.05% $MgSO_4{\cdot}7H_2O$, 1.5% $Na_2CO_3$ (pH 10.2)의 배지 조건에서 $30^{\circ}C$에서 96시간 배양하였을 때 가장 높은 효소생산인 0.9 unit/ml을 얻을 수 있었다.

Bacillus stearothermophilus KY-126가 생산하는 Cyclodextrin glycosyltransferase의 정제 및 특성

강상모,유시형,Kang, Sang-Mo,Yoo, Si-Hyung 한국식품과학회 1994 한국식품과학회지 Vol.26 No.4

토양을 대상으로 하여 CGTase를 생산하는 균주를 분리, 선별하여 Bacillus stearothermophilus KY-126을 얻었다. CGTase의 정제는 ammonium sulfate precipitation, ion exchange chromatography, gel filtration의 과정을 통해 분리 정제하여 단일 효소를 얻었으며, 분자량은 약 67,000이었다. 효소 반응의 최적 온도는 $65^{\circ}C$였으며, $55^{\circ}C$에서 30분간 열처리에도 비교적 열에 안정하였다. 최저 활성 pH는 5.5였고 pH5.5에서 10.5까지 비교적 안정하였다. $HgCl_{2}$에 의해 저해를 받았으며, 그 외의 금속 이온에는 저해를 받지 않았다. Soluble starch로부터 CD의 전환율은 43%이었으며, ${\alpha}-:,\;{\beta}-:,\;{\gamma}-$, CD의 생성 비율은 2.9 : 2.1 : 1이었다. A bacterial strain No. KY-126, which produced extracellular cyclodextrin glycosyltransferase(CGTase), was isolated from soil and identified as Bacillus stearothermophilus KY-126. The enzyme was purified by the treatments of ammonium sulfate precipitation, DEAF-Sephadex, Sephadex G-100 column chromatography. The optimal pH and temperature for the enzyme activity were pH 5.5 and $65^{\circ}C$, respectively. And the enzyme was stable at pH values from 6.0 to 11.0 at $55^{\circ}C$ for 30 min and stable up to $60^{\circ}C$ for 30 min.. The enzyme was inhibited by $HgCl_{2}$. The molecular weight of the enzyme was estimated to be 67,000 by using SDS-PAGE. The maximum conversion from starch to cyclodextrin (CD) by CGTase was 43% and obtained at 6 hr reaction and the ratio of ${\alpha}-,\;{\beta}-,\;{\gamma}-$, CD production at this time was 2.9 : 2.1 : 1.0.

호알칼리성 Bacillus sp. No. 4의 Cyclodextrin Glycosyltransferase에 의한 Glycosyl Sucrose의 생산과 저충치성 당으로서의 응용

손천배,유미경,김명희,문숙경 충남대학교부설 생명공학연구소 1992 생물공학연구지 Vol.2 No.-

Action of a cyclodextrin glycosyltransferase (CGTase) produce from alkalophilic Bacillus sp. No. 4 was studied in a solution containing starch and sucrose to prepare glycosyl sucrose syrup with good sweetness and antidecaying properties of teeth. In the initial stage of the reaction the CGTase produced cyclodextrin, however, the cyclodextrin disappeared and glycosyl sucrose was formed with the lapse of reaction time. The best proportion of sucrose to starch for prodution of glycosyl sucrose was about 1 : 1. The optimum pH and temperature of the coupling reaction was pH 6.0 and 60℃, respectively. Main composition of glycosyl sucrose syrup prepared with 20% starch and 20% sucrose was sucrose 18%, glucosyl sucrose (G_2F) 15.3% and amltosyl sucorse (G_3F) 11.3%. And glucose, maltose and maltotriose were produced very little. Smaller amounts of acid and insoluble glucan were formed in the syrup by Streptococcus mtans OMZ176 than in the sucrose. Therefore, the prepared glycosyl sucrose sucrose syrup is expected to prevent teeth from decaying.

Identification of Essential Histidines in Cyclodextrin Glycosyltransferase Isoform 1 from Paenibacillus sp. A11

( Jarunee Kaulpiboon ),( Piamsook Pongsawasdi ) 생화학분자생물학회 2003 BMB Reports Vol.36 No.4

The isoform 1 of cyclodextrin glycosyltransferase (CGTase, EC 2.4.1.19) from Paenibacillus sp. A11 was purified by a preparative gel electrophoresis. The importance of histidine, tryptophan, tyrosine, and carboxylic amino acids for isoform 1 activity is suggested by the modification of the isoform 1 with various group-specific reagents. Activity loss, when incubated with diethylpyrocarbonate (DEP), a histidine modifying reagent, could be protected by adding 25 mM methyl-β-cyclodextrin substrate prior to the modification. Inactivation kinetics of isoform 1 with DEP resulted in second-order rate constants (k_(inactivation)) of 29.5 M^(-1)s^(-1). The specificity of the DEP-modified reaction for the histidine residue was shown by the correlation between the loss of isoform activity and the increase in the absorbance at 246 nm of N-carbethoxyhistidine. The number of histidines that were modified by DEP in the absence and presence of a protective substrate was estimated from the increase in the absorbance using a specific extinction coefficient of N-carbethoxyhistidine of 3,200 M^(-1)cm^(-1). It was discovered that methyl-β-CD protected per mole of isoform 1, two histidine residues from the modification by DEP. To localize essential histidines, the native, the DEP-modified, and the protected forms of isoform 1 were digested by trypsin. The resulting peptides were separated by KPLC. The peptides of interest were those with R, 11.34 and 40.93 min. The molecular masses of the two peptides were 5,732 and 2,540 daltons, respectively. When the data from the peptide analysis were checked with the sequence of CGTase, then His-140 and His-327 were identified as essential histidines in the active site of isoform 1.

Identification of Essential Histidines in Cyclodextrin Glycosyltransferase Isoform 1 from Paenibacillus sp. A11

Kaulpiboon, Jarunee,Pongsawasdi, Piamsook Korean Society for Biochemistry and Molecular Biol 2003 Journal of biochemistry and molecular biology Vol.36 No.4

The isoform 1 of cyclodextrin glycosyltransferase (CGTase, EC 2.4.1.19) from Paenibacillus sp. A11 was purified by a preparative gel electrophoresis. The importance of histidine, tryptophan, tyrosine, and carboxylic amino acids for isoform 1 activity is suggested by the modification of the isoform 1 with various group-specific reagents. Activity loss, when incubated with diethylpyrocarbonate (DEP), a histidine modifying reagent, could be protected by adding 25 mM methyl-$\beta$-cyclodextrin substrate prior to the modification. Inactivation kinetics of isoform 1 with DEP resulted in second-order rate constants ($k_{inactivation}$) of $29.5\;M^{-1}s^{-1}$. The specificity of the DEP-modified reaction for the histidine residue was shown by the correlation between the loss of isoform activity and the increase in the absorbance at 246 nm of N-carbethoxyhistidine. The number of histidines that were modified by DEP in the absence and presence of a protective substrate was estimated from the increase in the absorbance using a specific extinction coefficient of N-carbethoxyhistidine of $3,200\;M^{-1}cm^{-1}$. It was discovered that methyl-$\beta$-CD protected per mole of isoform 1, two histidine residues from the modification by DEP. To localize essential histidines, the native, the DEP-modified, and the protected forms of isoform 1 were digested by trypsin. The resulting peptides were separated by HPLC. The peptides of interest were those with $R_t$ 11.34 and 40.93 min. The molecular masses of the two peptides were 5,732 and 2,540 daltons, respectively. When the data from the peptide analysis were checked with the sequence of CGTase, then His-140 and His-327 were identified as essential histidines in the active site of isoform 1.

Purification and Characterization of Cyclodextrin Glycosyltransferase from Alkalophilic Bacillus sp .

Chung, Yong Joon,Kong, In Soo,Kang, Yoon Suk,Yu, Ju Hyun 한국산업미생물학회 1990 한국미생물·생명공학회지 Vol.18 No.1

토양에서 분리한 호알카리성 Bacillus sp. YC-335가 생산하는 CGTase를 ethanol 침전법, DEAE-Toyopearl column chromatography, Sephadex G-100 column chromatography 방법 등에 의해 대량 정제하였다. 이 때 수율은 17.8%이었고 52.9배의 정제도를 가진 효소단백질을 얻을 수 있었다. 정제효소는 SDS-polyacrylamide gel 전기영동에 의해 분자량이 75,000 정도인 단일 peptide의 단백질임을 확인하였고 효소의 최적활성 pH는 6.0이었으며 pH 안정성은 pH 6-10까지 안정하였다. 최적활성온도는 50℃이었으며 열안정성은 50℃까지 안정하였고 이는 15mM CaCl_2에 의해 열안정성이 보호되었다. Alkalophilic Bacillus sp. YC-335 isolated from soil was capable of producing large amount of cyclodextrin glycosyltransferase(CGTase) in culture broth. This enzyme was successively purified 52.9 folds with 17.8 yield by ethanol precipitation, DEAE-Toyopearl column chromatography and Sephadex G-100 column chromatography. The purified enzyme have a molecular weight of approximately 75,000 estimated by SDS polyacrylamide gel electrophoresis. The optimum pH and temperature for the enzyme activity were 6.0 and 50℃, respectively. The enzyme was stable between pH 6 and 10, and up to 50℃. The thermostability of the enzyme was increased up to 60℃ by the addition of 15 mM CaCl_2.

Enzymatic Properties of Cyclodextrin Glycosyltransferase from Alkalophilic Bacillus sp. (Ⅱ)

Yong-Joon Chung,Do-Young Yum,Ju-Hyun Yu 한국식품과학회 1993 Food Science and Biotechnology Vol.2 No.1