• Journal of Microbiology
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• v.40 no.1
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• pp.26-32
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• 2002

From the culture supernatant of the psychrotrophic strain of Bacillus amyloliquefaciens an extracellular serine protease was purified to apparent homogeneity by successive purification steps using QAE-Sephadex, SP-Sephadex and Sephacryl S-100 column chromatography. The pretense is monomeric, with a relative molecular mass of 23,000. It is inhibited by the serine protease inhibitor phenylmethylsulfonyl fluoride, but not by EDTA. The enzyme is most active at pH 9-10 and at $45^{\circ}C$, although it is unstable at $60^{\circ}C$.

• The Korean Journal of Zoology
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• v.7 no.1
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• pp.19-22
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• 1964

The free amino acid content of Indian meal moth (Plodia interpunctella HUBNER) was analysed at various developmental stages by means of paper chromatography. 1) The free amino acids : present are alanine , arginine, aspartic acid, glutamic acid, glycine, histidine, leucine, methionine, proline, serine, threonine, tyrosine and valine. 2) Proline was detectable only in the acid-hydrolyzed Indian meal moth. 3) Arginine was clearly detected only in the larva stage. 4) Tyrosine methionine and valine were increased in the pupa stage. 5) Serine, glycine and tyrosine were present in high concentration in all stages.

• Journal of the Korean Chemical Society
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• v.34 no.6
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• pp.646-651
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• 1990

New optically active phosphonodipeptides were synthesized by coupling reaction of amino acids with 2-amino-3-(diethylphosphono)propionic acid methyl ester, prepared from L-serine.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.05a
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• pp.129-129
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• 2004

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.588-591
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• 2000

Serine palmitoyl transferase(SPT) and ceramidase are the key enzymes in sphingolipid biosynthesis. To study sphingolipid metabolism, we have got the 5'-upstream regions of human serine palmitoyl transferase subunit II and acid ceramidase gene by using GenomeWalker kits(Clontech Co.). Human genomic DNA was purified from HT29, human colon canser cell line by using DNAzol. We got several bands after secondary PCR and subcloned them to T7bule vector. Human SPTII promoter which we got was 2690bp but we cut it with Bgl II and vector with Bgl II and BamH I, and subcloned 1782bp to pGL2-enhancer vector and pGL2-basic vector with luciferase reporter gene. Human acid ceramidase promoter which we got were 2028bp and 1034bp and subcloned to pGL2-enhancer vector and pGL2-basic vector. We transfected these promoters to HT29 cell and assayed luciferase activity. For measuring transfection efficiency, pRL-TK vector with seapancy luciferase reproter gene was cotransfected with these promoters.

• Korean Journal of Microbiology
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• v.34 no.3
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• pp.82-86
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• 1998

An alkaline proteinase secreted from Yarrowia lipolytica 504D was purified by salting-out and column chromatography. The molecular weight of the purified enzyme was about 32,000 Da estimated by SDS-PAGE. The optimal condition for the activity of the enzyme was at pH 9.5 and $42^{\circ}C$ The enzyme was stable up to $45^{\circ}C$ and at the range of pH 4-10. Because the enzyme was inhibited by PMSF as well as EDTA, EGTA, and phenan-throlin, it is uncertain whether the enzyme is serine proteinase or metalloproteinase. However, almost all metal salts tested did not increase the enzyme activity, and Ca salt restored the activity of the enzyme inactivated by EDTA. Therefore, the purified enzyme seems to be an serine proteinase (E.C. 3.4.21.14).

• BMB Reports
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• v.33 no.2
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• pp.112-119
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• 2000

Three kinds of serine protease inhibitors, members of the Bowman-Birk trypsin inhibitor, were purified from Dolichos lablab seeds and named Dolichos protease inhibitor 1, 2 and 3 (DI-1, DI-2 and DI-3), respectively. Each inhibitor showed a single band with gel mobility at around 15.9, 12.1 and 14.6 kDa on 20% SDS-PAGE under reducing conditions. To characterize inhibitory specificity, the inhibition constant (Ki) for these inhibitors was measured against several known serine proteases. All three Dolichos protease inhibitors (DI-1, DI-2 and DI-3) inhibited the activity of trypsin and plasmin, but had no effect on thrombin and kallikrein (either for human plasma kallikrein or for porcine pancreas kallikrein). DI-1 inhibited chymotrypsin most effectively (Ki = $3.6{\times}10^{-9}\;M$), while DI-2 displayed inhibitory activity for porcine pancreatic elastase (Ki = $6.2{\times}10^{-8}\;M$). Pre-treatment of the 33 mg/kg of DI-mixture (active fractions from $C_{18}$ open column chromatography that included DI-1, DI-2 and DI-3) inhibited the induction of pseudomonal elastase-induced septic hypotension and prevented an increase in bradykinin generation in pseudomonal elastase-treated guinea pig plasma. Also, the increase of kallikrein activity, by injection of pseudomonal elastase, was inhibited by the pretreatment of the DI-mixture in a guinea pig. Since the DI-mixture had no inhibitory effect on kallikrein activity when Z-Phe-Arg-MCA was used as a substrate in vitro, its inhibitory activity in the pseudomonal elastase-induced septic hypotension model might not be due to a direct inhibition of plasma kallikrein in the activation cascade of the Hageman factor and prekallikrein system. These results suggest that the Dolichos DI-mixture might be used as an inhibitor in pathogenic bacterial protease-induced septic shock.

• Journal of Microbiology and Biotechnology
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• v.15 no.4
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• pp.866-872
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• 2005

H. pylori is known to cause severe gastric diseases, including peptic ulcers and gastric cancers, and a link has also been suggested with iron-deficiency anemia (IDA). However, little is known about the pathogenesis of H. pylori-associated IDA. In the present study, to determine whether H. pylori strains are correlated with the prevalence of IDA, we analyzed and compared the sequences of the napA genes encoding a bacterioferritin-like protein in H. pylori strains. A total of 20 H. pylori strains were isolated from antral biopsies of patients with and without IDA, and the napA genes amplified from the genomic DNA were sequenced. A comparison of the deduced amino acid sequences for NapA revealed two sites with major variations. At residue 70, five out of the 12 non-IDA strains ($41.7\%$) contained serine, while only one of the 8 IDA strains ($12.5\%$) contained serine, indicating a significantly higher frequency of serine in the non-IDA strains. In addition, the NapA proteins from all 17 Western strains available on Web sites were found to contain serine residues at this position. Meanwhile, the other major variation was located at residue 73, where all eight IDA strains ($100\%$) contained leucine, while this was only true for eight of the 12 non-IDA strains ($66.7\%$). Therefore, these results indicated that the strains within each group were more genetically related to each other than to strains in the other group. When the expression level of the napA genes in the H. pylori strains was measured using RT-PCR, no significant difference was observed between the two groups, suggesting a similar intensity for the inflammatory responses induced by the NapA protein among the strains. Consequently, when taken together, the present data suggest that the occurrence of H. pylori-associated IDA may be partly determined by the infecting H. pylori strain, and the non-IDA strains are more closely related to Western strains than the IDA strains.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1449-1459
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• 2015

A novel proteolytic enzyme with fibrinolytic activity, FSP3, was purified from the recently isolated Streptomyces sp. P3, which is a novel bacterial strain isolated from soil. FSP3 was purified to electrophoretic homogeneity by ammonium sulfate precipitation, anion exchange, and gel filtration. FSP3 is considered to be a single peptide chain with a molecular mass of 44 kDa. The maximum activity of the enzyme was observed at 50℃ and pH 6.5, and the enzyme was stable between pH 6 and 8 and below 40℃. In a fibrin plate assay, FSP3 showed more potent fibrinolytic activity than urokinase, which is a clinical thrombolytic agent acting as a plasminogen activitor. The activity was strongly inhibited by the serine protease inhibitor PMSF, indicating that it is a serine protease. Additionally, metal ions showed different effects on the activity. It was significantly suppressed by Mg²⁺ and Ca²⁺ and completely inhibited by Cu²⁺, but slightly enhanced by Fe²⁺. According to LC-MS/MS results, its partial amino acid sequences are significantly dissimilar from those of previously reported fibrinolytic enzymes. The sequence of a DNA fragment encoding FSP3 contained an open reading frame of 1287 base pairs encoding 428 amino acids. FSP3 is a bifunctional enzyme in nature. It hydrolyzes the fibrin directly and activates plasminogen, which may reduce the occurrence of side effects. These results suggest that FSP3 is a novel serine protease with potential applications in thrombolytic therapy.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1133-1139
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• 2013

Enzymatic decomposition of gelatin layers on used X-ray films and repeated utilization of the enzyme for potential application in silver recovery were investigated using keratinolytic serine proteases from Purpureocillium lilacinum LPS # 876. At pH 9.0, the enzymatic reaction was enhanced by the increase of enzyme concentration or by the increase of the temperature up to $60^{\circ}C$. Under the conditions of 6.9 U/ml, $60^{\circ}C$, and pH 9.0, hydrolysis of the gelatin layers and the resulting release of silver particles were achieved within 6 min. The protective effect of polyols against thermal denaturation was investigated. The presence of glycerol and propylene glycol increased enzyme stability. When the reusability of the enzyme for gelatin hydrolysis was tested, it could be seen that it could be effectively reused for more cycles when glycerol was added, compared with the enzyme without protective agents. The results of these repeated treatments suggested that a continuous process of recycling silver from used X-ray is feasible. Keeping in mind that recycling is (at the present time) needed and imperative, it can be remarked that, in this research, three wastes were successfully used: hair waste in order to produce serine proteases; glycerol in order to enhance enzyme thermal stability; and used X-ray films in order to recover silver and PET films.