The Experts below are selected from a list of 16002 Experts worldwide ranked by ideXlab platform
Philip E. Dawson - One of the best experts on this subject based on the ideXlab platform.
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synthesis of peptides and proteins without cysteine Residues by native chemical ligation combined with desulfurization
Journal of the American Chemical Society, 2001Co-Authors: Philip E. DawsonAbstract:The highly chemoselective reaction between unprotected peptides bearing an N-terminal Cys Residue and a C-terminal thioester enables the total and semi-synthesis of complex polypeptides. Here we extend the utility of this native chemical ligation approach to non-cysteine containing peptides. Since Alanine is a common amino acid in proteins, ligation at this Residue would be of great utility. To achieve this goal, a specific Alanine Residue in the parent protein is replaced with cysteine to facilitate synthesis by native chemical ligation. Following ligation, selective desulfurization of the resulting unprotected polypeptide product with H2/metal reagents converts the cysteine Residue to Alanine. This approach, which provides a general method to prepare alanyl proteins from their cysteinyl forms, can be used to chemically synthesize a variety of polypeptides, as demonstrated by the total chemical syntheses of the cyclic antibiotic microcin J25, the 56-amino acid streptococcal protein G B1 domain, and a var...
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synthesis of peptides and proteins without cysteine Residues by native chemical ligation combined with desulfurization
Journal of the American Chemical Society, 2001Co-Authors: Liang Z Yan, Philip E. DawsonAbstract:The highly chemoselective reaction between unprotected peptides bearing an N-terminal Cys Residue and a C-terminal thioester enables the total and semi-synthesis of complex polypeptides. Here we extend the utility of this native chemical ligation approach to non-cysteine containing peptides. Since Alanine is a common amino acid in proteins, ligation at this Residue would be of great utility. To achieve this goal, a specific Alanine Residue in the parent protein is replaced with cysteine to facilitate synthesis by native chemical ligation. Following ligation, selective desulfurization of the resulting unprotected polypeptide product with H(2)/metal reagents converts the cysteine Residue to Alanine. This approach, which provides a general method to prepare alanyl proteins from their cysteinyl forms, can be used to chemically synthesize a variety of polypeptides, as demonstrated by the total chemical syntheses of the cyclic antibiotic microcin J25, the 56-amino acid streptococcal protein G B1 domain, and a variant of the 110-amino acid ribonuclease, barnase.
Sandra Biroc - One of the best experts on this subject based on the ideXlab platform.
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human cathepsin o2 a matrix protein degrading cysteine protease expressed in osteoclasts functional expression of human cathepsin o2 in spodoptera frugiperda and characterization of the enzyme
Journal of Biological Chemistry, 1996Co-Authors: Dieter Bromme, Kathleen Okamoto, Bruce Wang, Sandra BirocAbstract:Abstract Cathepsin O2, a human cysteine protease predominantly present in osteoclasts, has been functionally expressed in Spodoptera frugiperda Sf9 cells using the Autographa californica nuclear polyhedrosis virus. Following in vitro activation at pH 4.0 with pepsin, active enzyme with an apparent molecular weight of 29,000 was obtained. N-terminal sequencing revealed the typical processing site for cysteine proteases of the papain family with a proline in the position adjacent to the N-terminal Alanine Residue. The SP subsite specificity of human cathepsin O2 is similar to cathepsin S but distinguished from cathepsins L and B. Similar to cathepsin S, cathepsin O2 is characterized by a bell-shaped pH activity profile and is stable at pH 6.5 for 30 min at 37°C. Cathepsin O2 is further distinguished by its potent collagenolytic activity against Type I collagen between pH 5 and 6, and elastinolytic activity against insoluble elastin at pH 7.0. Its capacity to efficiently degrade Type I collagen and its high expression in osteoclasts suggest that cathepsin O2 may play a major role in human osteoclastic bone resorption.
Dieter Bromme - One of the best experts on this subject based on the ideXlab platform.
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human cathepsin o2 a matrix protein degrading cysteine protease expressed in osteoclasts functional expression of human cathepsin o2 in spodoptera frugiperda and characterization of the enzyme
Journal of Biological Chemistry, 1996Co-Authors: Dieter Bromme, Kathleen Okamoto, Bruce Wang, Sandra BirocAbstract:Abstract Cathepsin O2, a human cysteine protease predominantly present in osteoclasts, has been functionally expressed in Spodoptera frugiperda Sf9 cells using the Autographa californica nuclear polyhedrosis virus. Following in vitro activation at pH 4.0 with pepsin, active enzyme with an apparent molecular weight of 29,000 was obtained. N-terminal sequencing revealed the typical processing site for cysteine proteases of the papain family with a proline in the position adjacent to the N-terminal Alanine Residue. The SP subsite specificity of human cathepsin O2 is similar to cathepsin S but distinguished from cathepsins L and B. Similar to cathepsin S, cathepsin O2 is characterized by a bell-shaped pH activity profile and is stable at pH 6.5 for 30 min at 37°C. Cathepsin O2 is further distinguished by its potent collagenolytic activity against Type I collagen between pH 5 and 6, and elastinolytic activity against insoluble elastin at pH 7.0. Its capacity to efficiently degrade Type I collagen and its high expression in osteoclasts suggest that cathepsin O2 may play a major role in human osteoclastic bone resorption.
Liang Z Yan - One of the best experts on this subject based on the ideXlab platform.
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synthesis of peptides and proteins without cysteine Residues by native chemical ligation combined with desulfurization
Journal of the American Chemical Society, 2001Co-Authors: Liang Z Yan, Philip E. DawsonAbstract:The highly chemoselective reaction between unprotected peptides bearing an N-terminal Cys Residue and a C-terminal thioester enables the total and semi-synthesis of complex polypeptides. Here we extend the utility of this native chemical ligation approach to non-cysteine containing peptides. Since Alanine is a common amino acid in proteins, ligation at this Residue would be of great utility. To achieve this goal, a specific Alanine Residue in the parent protein is replaced with cysteine to facilitate synthesis by native chemical ligation. Following ligation, selective desulfurization of the resulting unprotected polypeptide product with H(2)/metal reagents converts the cysteine Residue to Alanine. This approach, which provides a general method to prepare alanyl proteins from their cysteinyl forms, can be used to chemically synthesize a variety of polypeptides, as demonstrated by the total chemical syntheses of the cyclic antibiotic microcin J25, the 56-amino acid streptococcal protein G B1 domain, and a variant of the 110-amino acid ribonuclease, barnase.
Kathleen Okamoto - One of the best experts on this subject based on the ideXlab platform.
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human cathepsin o2 a matrix protein degrading cysteine protease expressed in osteoclasts functional expression of human cathepsin o2 in spodoptera frugiperda and characterization of the enzyme
Journal of Biological Chemistry, 1996Co-Authors: Dieter Bromme, Kathleen Okamoto, Bruce Wang, Sandra BirocAbstract:Abstract Cathepsin O2, a human cysteine protease predominantly present in osteoclasts, has been functionally expressed in Spodoptera frugiperda Sf9 cells using the Autographa californica nuclear polyhedrosis virus. Following in vitro activation at pH 4.0 with pepsin, active enzyme with an apparent molecular weight of 29,000 was obtained. N-terminal sequencing revealed the typical processing site for cysteine proteases of the papain family with a proline in the position adjacent to the N-terminal Alanine Residue. The SP subsite specificity of human cathepsin O2 is similar to cathepsin S but distinguished from cathepsins L and B. Similar to cathepsin S, cathepsin O2 is characterized by a bell-shaped pH activity profile and is stable at pH 6.5 for 30 min at 37°C. Cathepsin O2 is further distinguished by its potent collagenolytic activity against Type I collagen between pH 5 and 6, and elastinolytic activity against insoluble elastin at pH 7.0. Its capacity to efficiently degrade Type I collagen and its high expression in osteoclasts suggest that cathepsin O2 may play a major role in human osteoclastic bone resorption.