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Highly active and selective endopeptidases with programmed substrate specificities.

ABSTRACT: A family of engineered endopeptidases has been created that is capable of cleaving a diverse array of peptide sequences with high selectivity and catalytic efficiency (kcat/KM > 10(40 M(- 1) s(- 1)). By screening libraries with a selection-counterselection substrate method, protease variants were programmed to recognize amino acids having altered charge, size and hydrophobicity properties adjacent to the scissile bond of the substrate, including GluArg, a specificity that to our knowledge has not been observed among natural proteases. Members of this artificial protease family resulted from a relatively small number of amino acid substitutions that (at least in one case) proved to be epistatic.

SUBMITTER: Varadarajan N

PROVIDER: S-EPMC2654239 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Highly active and selective endopeptidases with programmed substrate specificities.

Varadarajan Navin N Rodriguez Sarah S Hwang Bum-Yeol BY Georgiou George G Iverson Brent L BL

Nature chemical biology 20080501 5

A family of engineered endopeptidases has been created that is capable of cleaving a diverse array of peptide sequences with high selectivity and catalytic efficiency (kcat/KM > 10(40 M(- 1) s(- 1)). By screening libraries with a selection-counterselection substrate method, protease variants were programmed to recognize amino acids having altered charge, size and hydrophobicity properties adjacent to the scissile bond of the substrate, including GluArg, a specificity that to our knowledge has no ...[more]

PMID: 18391948

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