• Journal of Microbiology and Biotechnology
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• 제5권5호
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• pp.269-273
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• 1995

A thermotolerable restriction endonuclease. Svil, found in Streptomyces violochromogenes D2-5 was purified. For the purification, streptomycin sulfate and ammonium sulfate precipitation was used. Ph osphocellulose P-ll, DEAE-Cellulose and Sephacryl-S200 HR colum chromatography were also performed. The purified enzyme was found to be homogeneous and the molecular weight of the enzyme estimated by polyacrylamide gel electrophoresis containing 0.1$%$ SDS was about 32, 000 daltons. The recognition sequence and cleavage site of the enzyme were determined to be $5^1$-$TT\downarrow CGAA$-$3^1$ which is the same sequence as that of Asull. Unlike Asull, however, the Svil shows high thermal stability.

• 한국동물학회지
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• 제35권4호
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• pp.466-473
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• 1992

Storage protein-1 (SP-1) of Gallerio mellonella was identified in hemolvmph and fat body by electrophoresis. SP-1 was purified from hemolvmph by KBr density gradient ultracentrifugation , DEAE-cellulose (DE52) ion-exchange chromatography, and gel permeation chromatography (Sephadex G-200). Purity of SP-1 was confirmed by Non-SDS PAGE and electron microscope. SP-1 is 9.4 nm in diameter and regular octahedron in shape. SP-1 has isoelectric point of 5.7 and native molecular weight of 365 K dalton and is composed of one type of subunit with molecular weight of 82 K dalton. Ttiacylslvcerol and phospholipid were found to be maior lipid components in SP-1.

• 한국식품조리과학회지
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• 제10권4호
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• pp.376-380
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• 1994

마늘의 alliinase를 ammonium sulfate 분획과 hydroxylapatite chromatography, concanavalin A-Sepharose affinity chromatography에 의해 정제하여, 23% 의 회수율과 7.6배 정제도를 나타내었다(specific activity 116.6 units/mg). SDS-polyacrylamide gel electrophoresis에서 단일 band를 나타내므로 순수한 aliinase 로 추측되며 이 효소의 분자량은 42K 로 추정된다. 기질로서 S-ethyl-L-cysteine sulfoxide를 사용한 이 효소의 $V_max$값은 2.27${\mu}$monl/mg.min이고 $K_m$은 1O mM이다 . 정제효소의 optimum pH는 6.5 phosphate buffer이며, 40$^{\circ}C$에서 최대활성을 나타내었다. Activation energy value($E^*$)는 4.6Kcal/mole로 추정된다.

• Food Science and Biotechnology
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• 제14권5호
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• pp.581-585
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• 2005

The antimicrobial activity of partially purified enterocin K25, produced by Enterococcus sp. K25, was abolished by proteases such as pepsin and proteinase K. The bacteriocin was resistant to heat treatment at $75^{\circ}C$ for 15 min and lost 75% of its activity at $100^{\circ}C$ for 30 min. Enterocin K25 showed bactericidal mode of action against an indicator strain, Lactobacillus plantarum NCDO 955. Enterocin K25 was purified to 112.6-fold purity via conventional steps of ammonium sulfate precipitation, ion exchange chromatography, and reversed phase high performance liquid chromatography (RP-HPLC). The molecular mass of the purified enterocin K25 was estimated as 4.3 kDa on an electrophoresis gel. Plasmid (${\sim}6.5\;kb$) linkage of production of enterocin K25 was confirmed by plasmid curing.

• Journal of Microbiology and Biotechnology
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• 제8권3호
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• pp.251-257
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• 1998

Cycloinulooligosaccharide fructanotransferase (CFTase) which produces cyclofructan from inulin was purified 332-fold from a culture broth of Bacillus macerans CFCl. The molecular mass of the CFTase was estimated to be 110 kDa by SDS-polyacrylamide gel electrophoresis and gel filtration, indicating that the enzyme has a monomer structure. The maximal level of enzyme activity was observed at pH 7.5 and $45^{\circ}C$. The enzyme was stable in the pH range 6.0 to 9.5, and at temperatures up to $45^{\circ}C$ for 1 h. The enzyme activity was completely inhibited in the presence of 0.5 mM $Ag^+\;or\;Cu^2+$ ion. None of sucrose (GF), l-kestose (GF2), or nystose (GF3) were found to be substrates for the CFTase, but inulooligosaccharides larger than nystose were attacked by the enzyme. The CFTase catalyzes not only the cyclization as the major reaction, but also disproportionation and coupling reactions involving intermolecular transfructosylation in the same manner as cyclodextrin glucanotransferase (CGTase) (EC 2.4.1.19).

• BMB Reports
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• 제38권2호
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• pp.232-237
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• 2005

A glutathione S-transferase (GST) from Lactuca sativa was purified to electrophoretic homogeneity approximately 403-fold with a 9.6% activity yield by DEAE-Sephacel and glutathione (GSH)-Sepharose column chromatography. The molecular weight of the enzyme was determined to be approximately 23,000 by SDS-polyacrylamide gel electrophoresis and 48,000 by gel chromatography, indicating a homodimeric structure. The activity of the enzyme was significantly inhibited by S-hexylGSH and S-(2,4-dinitrophenyl) glutathione. The enzyme displayed activity towards 1-chloro-2,4-dinitrobenzene, a general GST substrate and high activities towards ethacrynic acid. It also exhibited glutathione peroxidase activity toward cumene hydroperoxide.

• 약학회지
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• 제36권3호
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• pp.241-249
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• 1992

The whole body extract of Lunella coronata coreensis agglutinated nonspecifically human and other animal erythrocytes. A new lectin was purified by the following procedures: 0.15 M NaCl extraction, salt fractionation, gel filtration, anionic and cationic ion exchange column chromatographies. Through these purification procedures, specific activity of LCC-I was increased from 276 to 9714.3 units/mg, And on polyacrylamide gel electrophoresis, LCC-I exhibited one major band. A molecular weight of LCC-I was assumed to be 20,000 by sodium dodesyl sulfate polyacrylamide gel electrophoresis. The purified lectin was relatively stable at various pH and heat. Among the tested sugars, lactose and lactulose inhibited lectin activity at a concentration of 6.25 mM, respectively.

• BMB Reports
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• 제31권6호
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• pp.585-589
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• 1998

The herpes simplex virus type-1 (HSV-1)-encoded DNA polymerase consists of two subunits, the products of the UL30 and UL42 genes. UL30 and UL42 were coexpressed in Sf9 cells infected with recombinant baculoviruses carrying the two genes. The UL30 and UL42 gene products remained tightly associated throughout the purification, which led to a near homogeneous heterodimer composed of the DNA polymerase and UL42 protein. The DNA polymerase-UL42 protein heterodimer, purified from the recombinant baculovirus-infected Sf9 cells, showed the same high degree of processivity of deoxynucleotide polymerization as the enzyme purified from the HSV-1 infected primate cells. Like the latter, it contained a 3'-5' exonuclease activity that specifically hydrolyzes an incorrectly matched nucleotide at the 3' terminus of a primer, thereby contributing to the fidelity of DNA replication.

• 미생물학회지
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• 제38권4호
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• pp.254-259
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• 2002

저온에서 최적 생육을 보이는 저온성 균주를 남극해양에서 분리하여 생화학적 특성 및 165 rRNA 염기서열로부터 Shewanella sp.에 속하는 균주로 동정하고 Shewanella sp. L93으로명명하였다. 본 균주에서 생산되는 저온성 세포외 단백질 분해 효소(extracellular protease)를 ammonium sulfate precipitation, High-Q column chromatography, 일차 gel permeation chromatography, BioScale Q2 ion exchange chromatography 및 gel permeation chromatography를 통하여 purification fold 19.3, yield 0.7 %로 정제하였고 그 특성을 조사하였다.

• Journal of Microbiology
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• 제34권1호
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• pp.82-89
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• 1996

Purine nucleoside phosphorylase (PNP) was purified in Micrococcus luteus (M. luteus) using streptomycin sulfate and amomonium sulfate fractionation, three times by a Sephadex G-100 gel filtration and a DEAE-Sephadex A-50 ion exchange chromatography. The enzyme was purified 72 folds with a 11% recovery and showed a single band in a nondenaturing gel electrophoresis. The M. W. of PNP turned out to be 1.35 * 10$^{5}$ delton in G-150 gel filtration chromatography. The stability of the enzyme was increased by treatment with both substrates, MgCI$_{2}$ or CaCI$_{2}$, but not significantly kcal/mol. M. luteus PNP catalyzed the phosphorolysis of inosine, deoxyinosine, guanosine and deoxyguanosine with the Km value of 1.5 * 10$^{-3}$ M, 3.0 * 10$^{-3}$ M, 5.0 * 10$^{-4}$ M, respectively. The enzyme was reacted with adenosine, 1-methylnosine and 1-methylguanosine as substrates, which were shown to be poor substrates for mammalian enzyme.