• Applied Biological Chemistry
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• 제15권2호
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• pp.111-142
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• 1972

청국장(淸國醬)메주 발효과정중(醱酵過程中) 경시적(輕時的)인 시료(試料)를 체취(採取)하여 cross linkage가 각각(各各) 다른 5개(個)의 Dowex-50 resin을 충전(充塡)한 column을 통과(通過)시켜 얻은 Dowex-50의 X-16 fraction의 저급(低級) peptide의 종류(種類)를 구명(究明)하는 동시(同時)에 청국장(淸國醬)메주발효과정중(醱酵過程中)에 생성(生成)되는 저급(低級) peptide의 N-terminal amino acid 와 C-terminal amino acid를 동정(同定)하고 각(各) peptide 군(群)의 구성(構成) amino acid의 종류(種類)를 결정(決定)하여 다음과 같은 결과(結果)를 얻었다. 1. 각(各) peptide군(群)의 N 및 C-terminal amino acid 와 구성(構成)아미노산(酸은) 다음과 같다. [P]-I. Pro (Cys Ala Asp Trp Ile Val) Glu [P]-II. Val (His Arg Glu Thr Ala Met) Asp [P]-III. Glu (Cys Lys Asp Thr Met) Ala [P]-IV. Glu(His Ser Ala) Met) [P]-V. Ile (Cys Asp Arg Gly Pro T.p Phe) His [P]-VI. Gly(Asp ser) Lys [P]-VII. Thr(Pro Tyr Phe) Asp [P]-VIII. Phe(Tyr Leu Ile) Val [P]-IX. Trp (Phe lle) Thr [P]-X. Ile (Arg Leu) Phe [P]-XI. Asp (Lys His Ser Gly Glu Pro) Ala [P]-XII. Glu (Cys Asp Gly) Ser [P]-XIII. Ala (Arg Tyr) Glu [P]-XIV. Met (Glu Ala) His 2. 청국장(淸國醬)메주 발효과정중(醱酵過程中)의 경시적(輕時的)인 시료(試料)의 각저급(各低級) peptide 군(群)에는 2종(種), 3종(種) 및 6종(種)의 아미노산(酸)으로 되어있는 peptidessm 찾아볼 수 없으며 구성(構成) 아미노산(酸)도 $4{\sim}9$종의 아미노산(酸)으로 결합(結合)되어 있는 peptide 군(群)들의 혼합물(混合物)로 되어 있다. 3. Bacillus Subtilis K-27 균주(菌株)의 protease는 그 작용(作用) specificity가 Aspergillus soya 나 pepsin, chymotrypsin 및 trysin 보다 넓다.

• BMB Reports
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• 제34권3호
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• pp.244-249
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• 2001

The anabolic acetolactate synthase III was purified to homogeneity from Serratia marcescens using DEAE-Sepharose, Phenyl-Sepharose, and hydroxylapatite column chromatography The native molecular weight of the enzyme was approximately 165 kDa. The enzyme is composed of two large and two small subunits with molecular weights of 64 and 15 kDa, respectively. The N-terminal sequence of the large and small subunit of the enzyme was Ser-Ala-Thr-Pro-Gln-Pro-Ser-Thr-Arg-Phe-Thr-Cys-Ala-Gln-Leu-Ile-Ala-His-Leu and Met-Leu-Gln-Pro-Gln-Asp-Lys-Pro-Gln-Val-Ile-Leu-Glu-Leu-Ala-Val-Arg-Asn-His-Pro-Gly-Val-Met-Ser-His-Val, respectively. The optimum pH and pI value were 7.5 and 5.5, respectively The $IC_{50}$ values were $20\;{\mu}M$ and $14\;{\mu}M$ for valine and herbicide SU7, respectively. The substrate specificity ratio, R value, was determined to be approximately 40, which suggests that this enzyme prefers the formation of $\alpha$-aceto-$\alpha$-hydroxybutyrate leading to the synthesis of isoleucine.

• 약학회지
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• 제38권5호
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• pp.530-543
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• 1994

To study the feasibility of transmucosal delivery of leucine enkephalin (Leu-Enk) and $[D-ala^2]$-leucine enkephalinamide (YAGFL), their degradation extents and pathways in various rabbit mucosa extracts were investigated by high performance liquid chromatography. The degradation of Leu-Enk and YAGFL was observed to follow the first-order kinetics. The degradation half-lives of Leu-Enk in the nasal, rectal and vaginal mucosal extracts were 1.62, 0.37 and 1.12 hrs and those of YAGFL were 30.55, 9.70 and 6.82 hrs, respectively, indicating Leu-Enk was degraded in a more extensive and rapid manner than YAGFL. But the mucosal and serosal extracts of the same mucosa showed the similar degradation rates for both pentapeptides. The degradation was most rapid in the neutral pH and increasing concentrations of substrates retarded the degradation rates. The maior hydrolytic fragments of Leu-Enk were Des-Tyr-Leu-Enk and tyrosine, indicating the enzymatic hydrolysis by aminopeptidases. However, the data also suggested endopeptidases such as dipeptidyl carboxypeptidase and dipeptidyl aminopeptidase could play some role in the degradation of Leu-Enk. On the other hand, the hydrolytic fragments of YAGFL in all the mucosa extracts were mainly Tyr-D-Ala-Gly and Phe-Leu-Amide, demonstrating the hydrolytic breakdown by endopeptidases. The degradation pathways were further explored by concomitantly determining the formation of smaller metabolites of primary hydrolytic fragments of Leu-Enk and YAGFL in the mucosa extracts.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.563-568
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• 2010

The Val289 residue in the $\alpha$-amylase of Bacillus amyloliquefaciens, which is equivalent to the Ala289 and Val286 residues in the $\alpha$-amylases of B. stearothermophilus and B. licheniformis, respectively, was studied by site-directed mutagenesis. This residue was substituted with 10 different amino acids by random substitution of the Val codon. In these mutant $\alpha$-amylases, Val289 was substituted with Ile, Tyr, Phe, Leu, Gly, Pro, Ser, Arg, Glu, and Asp. Compared with the wild-type $\alpha$-amylase, the mutant $\alpha$-amylase Val289Ile showed 20% more hydrolytic activity, whereas Val289Phe and Val289Leu showed 50% lesser activity. On the other hand, the mutant $\alpha$-amylases Val289Gly, Val289Tyr, Val289Ser, and Val289Pro showed less than 15% activity. The substitution of Val289 with Arg, Asp, or Glu resulted in complete loss of the $\alpha$-amylase activity. Interestingly, the mutant $\alpha$-amylase Val289Tyr had acquired a transglycosylation activity, which resulted in the change of product profile of the reaction, giving a longer oligosaccharide.

• 미생물학회지
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• 제36권1호
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• pp.14-19
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• 2000

Penicillium oxalicum(HCLF-34)의 세포외 분비효소로부터 ultrafilration, gel filtration chromatograph와 anion exchange chromatography법을 이용하여 남조세균(Anabaena cylindrica) 분해효소를 분리하였다. 이 효소의 분자량은 약 22 kDa이며, renaturation SDS-PAGE에서 monomer로서 남조세균 분해 활성을 갖는다. 아미노산 서열은 N-말단부터$NH_(2)$-Glu-Ser-Tyr-Ser-Ser-Asn-Ala-Ala-Gly-Ala-Val-Leu-Ile---, 13개의 아미노산을 분석하였으며, 분석된 아미노산의 homology를 조사한 결과 aspergillopepsin II precursor(acid protease A)와 13개의 아미노산 중 11개(84%)의 유사도를 나타내었고, acid proteinase EapC precursor과 13개 중 10개(81%)의 유사도를 나타내었다.

• 약학회지
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• 제33권6호
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• pp.339-344
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• 1989

The alkaline protease produced by Sarcodon aspratus(Berk) S. Ito. was purified from its fruit bodies. The enzyme was purified by using ammonium sulfate fractionation, tris-acryl CM-cellulose column chromtography and chromatofocusing. The protease migrated as one major band with a molecular weight of about 29,000 dalton on sodium dodecylsulfate-polyacrylamide gel electrophoresis. The amino acid sequence of the N-terminal residues(21) of the enzyme was determined by automated sequence analysis. The sequence was Val-Thr-Thr-Lys-Gln-Thr-Asn-Ala-Pro-Trp-Gly-Leu-Gly-Asn-Ile-Ser-Thr-Thr-Asn-Lys-Leu. Comparison of this sequence with the N-terminal sequence of the p-roteinase K from Tritirachium album showed high similarity, i. e. 57.8% identical residues. The protease displayed a relatively high stability in sodium dodecyl sulfate.

• 한국미생물·생명공학회지
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• 제20권6호
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• pp.655-662
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• 1992

알칼리내성 Bacillus sp. Ya-14 유래의 pectate lyase 유전자를 함유한 재조합균주로부터 affinity method, CM-cellose column chromatography와 gel filtration을 통해 효소를 정제하였으며 정제효소의 수율은 10.2, 정제도는 258배였다. 효소의 최적활성 pH는 10.0이었고 pH4.0-10.0까지의 범위에서 안정성이 있었으며, 최적활성온도는 $60^{\circ}C$이고 $50^{\circ}C$까지 열안정성이 있으며, SDS-PASGE에 의해 추정된 분자량은 43KDa 이었다. 아미노산 조정 분석 결과 polar, basic 아미노산의 함량이 높고 특히 Ser, Gly, Tyr의 함량이 높았으며, 정제효소의 N-terminal은 Ala-Asp-Leu-Gly-His-Gln-Thr의 아미노산 서열이었다.

• Preventive Nutrition and Food Science
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• 제13권3호
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• pp.196-203
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• 2008

Hwangtae, dried Alaska pollack, is a major storage product in the fish processing industry. Hwangtae is prepared by removing the internal organs and drying outdoors during the cold witner months by allowing it to thaw during the daytime and re-freeze at night under sub-zero ($-10^{\circ}C$) conditions and gradually dry from December until the next April for around 5 months from Myungtae. In this study, ground Hwangtae was hydrolyzed using two proteolytic enzymes (pepsin and alcalase) which produced five soluble active peptides from Hwangtae (yellowish dried Pollack, Theragra chalcogramma) protein. Two different peptides with strong antioxidative activity were isolated from the hydrolysate using consecutive chromatographic methods of Sephadex G-25 gel, ion-exchange chromatography on a Sepharose-Sephadex C-25 gel, and high-performance liquid chromatography. The isolated peptides, APO1 and APO2, were composed of 16 and 13 amino acid residues, respectively. Both peptides contained a Gly residue at the C-terminus and the repeating motif Gly-Pro-Hyp. The peptide with a molecular weight less than 1,000 Daltons (APACE) obtained from enzymatic hydrolysates of Hwangtae exhibited the highest ACE inhibitory activity. The APACE peptides was composed of 4 amino acid residues (Gly-Leu-Leu-Pro). These results suggest that Hwangtae hydrolysates could be a good source of peptides with ACE inhibitory activity. Biochemical analysis indicated that two 70 kDa peptides (APG1 and APG2) isolated from the hydrolysate had gelatinoytic activity, which was shown to be a calcium dependent protease type as showed by gelatin SDS PAGE.

• 생명과학회지
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• 제22권4호
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• pp.499-507
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• 2012

군소인 Aplysia kurodai의 중추신경절로부터 발견된 myomodulin A (MMA, PMSMLRLamide)와 myomodulin E (MME, GLQMLRLamide)는 $Mytilus$ $edulis$의 anterior byssus retractor muscle (ABRM)을 활성측정시스템으로 사용하여 정제되었다. 정제된 MMA와 MME는 연체동물에서 발견된 myomodulin 계열의 펩타이드와 동일한 일차구조를 지닌다. MME의 구조와 활성간의 상관관계를 알아보기 위해서 MME, 유도체 및 다른 신경성 펩타이드들을 합성하였다. MME의 유도체인 Des[$Gly^1$]-MME, Des[$Gly^1,Leu^2$]-MME 및 Des[$Gly^1,Leu^2,Gln^3$]-MME의 일차구조는 각각 LQMLRLamide, QMLRLamide 및 MLRLamide이다. 합성 물질들을 사용하여 ABRM에 대한 phasic contraction을 측정하였다. MME는 $1{\times}10^{-9}$ M 또는 더 높은 농도에서 ABRM의 phasic contraction을 저해하였다. 또한 MME는 $1{\times}10^{-8}$ M에서 catch-tension에 대해 이완활성을 나타내었다. 합성 펩타이드들을 사용하여 Africa giant snail, $Achatina$ $fulica$의 소낭과 penial retractor muscle에 대해서도 활성을 측정하였다. MME와 유도체들은 소낭에 대해서는 수축반응을 보였지만, penial retractor muscle에 대해서는 이완 활성을 나타내었다. 이러한 결과들은 MME와 그 유도체들은 연체동물의 다양한 조직에 대해 조절 효과를 가지고 있다는 것을 의미한다. 본 연구는 생체 내에서 발생하는 신경 및 circuit의 변화를 조절하는 작용 연구에 대한 기본적인 자료가 될 것이다.

• 생명과학회지
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• 제10권2호
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• pp.140-149
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• 2000

In order to utilize marine processing waste which would normally be discarded, cod liver protein was hydrolysed by ${\alpha}$-chymotrysin, and the hydrolysate was investigated for the new angiotensin I converting enzyme (ACE) inhibitor. Thy hydrolysate was separated into three major types, with molecular weight cut-off (MWCO) values less than 10 kDa, 5 kDa and 1 kDa of ultrafiltration membranes, respectively. ACE inhibitory peptides were isolated from the fractions passed through MWCO 1 kDa membrane, and purified by using ion-exchange chromatography on a SP-Sephadex C-25 column, gel filtration on a Sephadex G-15 column, and HPLC on an ODS column. The purity was identified with capillary electrophoresis. The amino acid sequences of two peptides were Met-Ile-Pro-Pro-Tyr-Tyr (IC50=10.9 ${\mu}$M) and Gly-Leu-Arg-Asn-Gly-Ile (IC50=35.0 ${\mu}$M)