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Generation of Ca2+-independent sortase A mutants with enhanced activity for protein and cell surface labeling.

ABSTRACT: Sortase A, a calcium-dependent transpeptidase derived from Staphylococcus aureus, is used in a broad range of applications, such as the conjugation of fluorescent dyes and other moieties to proteins or to the surface of eukaryotic cells. In vivo and cell-based applications of sortase have been somewhat limited by the large range of calcium concentrations, as well as by the often transient nature of protein-protein interactions in living systems. In order to use sortase A for cell labeling applications, we generated a new sortase A variant by combining multiple mutations to yield an enzyme that was both calcium-independent and highly active. This variant has enhanced activity for both N- and C-terminal labeling, as well as for cell surface modification under physiological conditions.

SUBMITTER: Jeong HJ

PROVIDER: S-EPMC5714338 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Generation of Ca2+-independent sortase A mutants with enhanced activity for protein and cell surface labeling.

Jeong Hee-Jin HJ Abhiraman Gita C GC Story Craig M CM Ingram Jessica R JR Dougan Stephanie K SK

PloS one 20171204 12

Sortase A, a calcium-dependent transpeptidase derived from Staphylococcus aureus, is used in a broad range of applications, such as the conjugation of fluorescent dyes and other moieties to proteins or to the surface of eukaryotic cells. In vivo and cell-based applications of sortase have been somewhat limited by the large range of calcium concentrations, as well as by the often transient nature of protein-protein interactions in living systems. In order to use sortase A for cell labeling applic ...[more]

PMID: 29200433

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