The Experts below are selected from a list of 1107 Experts worldwide ranked by ideXlab platform
Yoshihiko Ueno - One of the best experts on this subject based on the ideXlab platform.
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A new procedure for enzymatic semisynthesis of human insulin by hydrolysis of single‐chain des‐(b‐30)‐lnsulin precursor with Lysyl Endopeptidase
Biotechnology and Bioengineering, 1991Co-Authors: Kazuyuki Morihara, Yoshihiko UenoAbstract:It has been shown that the single-chain des-(B-30)-insulin precursor (SCI) can be converted into human insulin ester by transpeptidation using trypsin in the presence of a threonine derivative. The present study demonstrates that Achromobacter lyticus protease 1 (Lysyl Endopeptidase) can catalyze the transpeptidation reaction more efficiently than can trypsin. It is also shown that des-(B-30)-insulin (DAI) can be produced by hydrolysis of SCI with the Lysyl Endopeptidase. Since it is well known that SCI can be produced by gene technology, the following method is recommended for industrial production of human insulin ester: hydrolysis of SCI with Lysyl Endopeptidase followed by coupling of the resulting DAI with a threonine derivative using trypsin or Lysyl Endopeptidase.
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a new procedure for enzymatic semisynthesis of human insulin by hydrolysis of single chain des b 30 lnsulin precursor with Lysyl Endopeptidase
Biotechnology and Bioengineering, 1991Co-Authors: Kazuyuki Morihara, Yoshihiko UenoAbstract:It has been shown that the single-chain des-(B-30)-insulin precursor (SCI) can be converted into human insulin ester by transpeptidation using trypsin in the presence of a threonine derivative. The present study demonstrates that Achromobacter lyticus protease 1 (Lysyl Endopeptidase) can catalyze the transpeptidation reaction more efficiently than can trypsin. It is also shown that des-(B-30)-insulin (DAI) can be produced by hydrolysis of SCI with the Lysyl Endopeptidase. Since it is well known that SCI can be produced by gene technology, the following method is recommended for industrial production of human insulin ester: hydrolysis of SCI with Lysyl Endopeptidase followed by coupling of the resulting DAI with a threonine derivative using trypsin or Lysyl Endopeptidase.
Kazuyuki Morihara - One of the best experts on this subject based on the ideXlab platform.
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Use of Bacillus brevis for synthesis and secretion of Des-B30 single-chain human insulin precursor.
Bioscience Biotechnology and Biochemistry, 2000Co-Authors: Mamoru Koh, Kazuyuki Morihara, Hiroshi Hanagata, Shogo Ebisu, Hiroaki TakagiAbstract:A synthetic gene encoding a single chain human insulin precursor [B-chain (1-29)-A-chain] linked to the C-terminal lysine of human epidermal growth factor (1-28) (EGF-SCI) was constructed. This gene was expressed using Bacillus brevis. EGF-SCI was isolated from the supernatant of the culture broth. Treatment of EGF-SCI with Lysyl Endopeptidase resulted in the formation of des-B30 human insulin. The identification of the formed des-B30 human insulin was made by the measurement of molecular weight and amino acid analysis. The binding coefficient to anti-human insulin antibody was comparable to that of human insulin.
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A new procedure for enzymatic semisynthesis of human insulin by hydrolysis of single‐chain des‐(b‐30)‐lnsulin precursor with Lysyl Endopeptidase
Biotechnology and Bioengineering, 1991Co-Authors: Kazuyuki Morihara, Yoshihiko UenoAbstract:It has been shown that the single-chain des-(B-30)-insulin precursor (SCI) can be converted into human insulin ester by transpeptidation using trypsin in the presence of a threonine derivative. The present study demonstrates that Achromobacter lyticus protease 1 (Lysyl Endopeptidase) can catalyze the transpeptidation reaction more efficiently than can trypsin. It is also shown that des-(B-30)-insulin (DAI) can be produced by hydrolysis of SCI with the Lysyl Endopeptidase. Since it is well known that SCI can be produced by gene technology, the following method is recommended for industrial production of human insulin ester: hydrolysis of SCI with Lysyl Endopeptidase followed by coupling of the resulting DAI with a threonine derivative using trypsin or Lysyl Endopeptidase.
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a new procedure for enzymatic semisynthesis of human insulin by hydrolysis of single chain des b 30 lnsulin precursor with Lysyl Endopeptidase
Biotechnology and Bioengineering, 1991Co-Authors: Kazuyuki Morihara, Yoshihiko UenoAbstract:It has been shown that the single-chain des-(B-30)-insulin precursor (SCI) can be converted into human insulin ester by transpeptidation using trypsin in the presence of a threonine derivative. The present study demonstrates that Achromobacter lyticus protease 1 (Lysyl Endopeptidase) can catalyze the transpeptidation reaction more efficiently than can trypsin. It is also shown that des-(B-30)-insulin (DAI) can be produced by hydrolysis of SCI with the Lysyl Endopeptidase. Since it is well known that SCI can be produced by gene technology, the following method is recommended for industrial production of human insulin ester: hydrolysis of SCI with Lysyl Endopeptidase followed by coupling of the resulting DAI with a threonine derivative using trypsin or Lysyl Endopeptidase.
Kin-ichiro Miura - One of the best experts on this subject based on the ideXlab platform.
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Alteration of the Specificity of the Streptomyces Subtilisin Inhibitor by Gene Engineering
Bio Technology, 1990Co-Authors: Shuichi Kojima, Shusei Obata, Izumi Kumagai, Kin-ichiro MiuraAbstract:We have altered the amino acid at the center of the reactive site (methionine 73) of Streptomyces subtilisin inhibitor (SSI) by site-directed and cassette mutagenesis. Replacement by lysine or arginine resulted in trypsin inhibitory activity, replacement only by lysine gave inhibition of Lysyl Endopeptidase, and replacement by tyrosine or tryptophan resulted in inhibition of α-chymotrypsin. The four mutant SSIs retained their native activity against subtilisin BPN′.Thus by altering only one amino acid residue at the reactive site of SSI to the substrate specificity of the respective protease we could successfully change its inhibitory profile.
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Effect on inhibitory activity of mutation at reaction site P4 of the Streptomyces subtilisin inhibitor, SSI
"Protein Engineering Design and Selection", 1990Co-Authors: Kojima Shuichi, Izumi Kumagai, Kin-ichiro MiuraAbstract:The protein Streptomyces subtilisin inhibitor, SSI, efficiently inhibits a bacterial serine protease, subtilisin BPN'. We recently demonstrated that functional change in SSI was possible simply by replacing the amino acid residue at the reactive P1 site (methionine 73) of SSI. The present paper reports the additional effect of replacing methionine 70 at the P4 site of SSI (Lys73) on inhibitory activity toward two types of serine proteases, trypsin (or Lysyl Endopeptidase) and subtilisin BPN'. Conversion of methionine 70 at the P4 site of SSI(Lys73) to glycine or alanine resulted in increased inhibitory activity toward trypsin and Lysyl Endopeptidase, while replacement with phenylalanine weakened the inhibitory activity toward trypsin. This suggests that steric hindrance at the P4 site of SSI(Lys73) is an obstacle for its binding with trypsin. In contrast, the same P4 replacements had hardly any effect on inhibitory activity toward subtilisin BPN'. Thus the subsite structure of subtilisin BPN' is tolerant to these replacements. This contrast in the effect of P4 substitution might be due to the differences in the S4 subsite structures between the trypsin-like and the subtilisin-like proteases. These findings demonstrate the importance of considering structural complementarity, not only at the main reactive site but also at subsites of a protease, when designing stronger inhibitors.
Hideo Hatate - One of the best experts on this subject based on the ideXlab platform.
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Isolation of an active peptide fragment from human serum albumin and its synergism with α-tocopherol
Journal of the American Oil Chemists' Society, 1998Co-Authors: Hideo HatateAbstract:An active peptide was isolated from hydrolysates of human serum albumin. This peptide was initially isolated by gel permeation chromatography and subsequent reversed-phase high-performance liquid chromatography. This active peptide, composed of 10 amino acid residues, was further hydrolyzed with a Lysyl Endopeptidase to give two peptide fragments. Only one fragment, identified as the tetrapeptide Leu-Gln-His-Lys, was found to have activity comparable to the original peptide and corresponded to the amino acid residues 103–106 of human serum albumin. Among these four amino acid residues, the His-Lys sequence seemed to be important in the occurrence of potent activity by comparison of the structural similarity with another active tetrapeptide, Asp-Thr-His-Lys, which had been previously isolated from bovine serum albumin hydrolysates. In addition, the active fragment showed potent synergism by preventing consumption of α-tocopherol during the autoxidation of linoleic acid.
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Isolation of an active peptide fragment from human serum albumin and its synergism with α‐tocopherol
Journal of the American Oil Chemists' Society, 1998Co-Authors: Hideo HatateAbstract:An active peptide was isolated from hydrolysates of human serum albumin. This peptide was initially isolated by gel permeation chromatography and subsequent reversed-phase high-performance liquid chromatography. This active peptide, composed of 10 amino acid residues, was further hydrolyzed with a Lysyl Endopeptidase to give two peptide fragments. Only one fragment, identified as the tetrapeptide Leu-Gln-His-Lys, was found to have activity comparable to the original peptide and corresponded to the amino acid residues 103–106 of human serum albumin. Among these four amino acid residues, the His-Lys sequence seemed to be important in the occurrence of potent activity by comparison of the structural similarity with another active tetrapeptide, Asp-Thr-His-Lys, which had been previously isolated from bovine serum albumin hydrolysates. In addition, the active fragment showed potent synergism by preventing consumption of α-tocopherol during the autoxidation of linoleic acid.
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Enhancement of Antioxidative Activity of .ALPHA.-Tocopherol and Sodium Ascorbate Using Tetrapeptide Prepared from Bovine Serum Albumin Hydrolysates.
Food Science and Technology International Tokyo, 1997Co-Authors: Hideo Hatate, Yoichiro Hama, Toshiyoshi Araki, Nobutaka SuzukiAbstract:The tetrapeptide originating from a peptide synergist consisting of 21 amino acid residues (peptide C-1) was found to increase the antioxidative activity of α-tocopherol (Toc) and sodium ascorbate (AsA). Peptide C-1, which had been previously isolated from bovine serum albumin hydrolysates, was again hydrolyzed with a Lysyl Endopeptidase to give three peptide fragments. Each fragment was tested for its synergistic effect with Toc and AsA, and only one fragment had a potent synergism comparable to the original peptide, C-1. The structure of the active fragment was confirmed as the tetrapeptide, Asp-Thr-His-Lys, by amino acid analysis and sequence determination. In addition, peptide C-1 and its active fragment corresponded to residues 1 to 21 and 1 to 4 of BSA, respectively.
Kenichiro Hayashi - One of the best experts on this subject based on the ideXlab platform.
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the two subunits of a phospholipase a2 inhibitor from the plasma of thailand cobra having structural similarity to urokinase type plasminogen activator receptor and ly 6 related proteins
Biochemical and Biophysical Research Communications, 1994Co-Authors: Naoki Ohkura, S Inoue, Kazuya Ikeda, Kenichiro HayashiAbstract:Amino acid sequences of the two subunits (31-kDa and 25-kDa subunits) of a phospholipase A2 (PLA2) inhibitory protein, purified from the blood plasma of Thailand cobra Naja naja kaouthia, were determined by alignment of peptides obtained by Lysyl Endopeptidase, staphylococcal V8 protease and endoproteinase Asp-N digestions. The respective subunits were composed of 188 and 185 amino acid residues, and the former contained one asparagine-linked sugar chain at the position 157. There was 29% identity between 31-kDa and 25-kDa subunits. The analysis of internal homology in each sequence of the two subunits revealed the existence of two repeats of approximately 90 amino acid residues. These sequence units were found to be significantly homologous to those of urokinase-type plasminogen activator receptor and of Ly-6 related proteins, such as Ly-6A/E, Ly-6C, ThB, and CD59 antigens.
