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Tyrosinase-catalyzed site-specific immobilization of engineered C-phycocyanin to surface.

ABSTRACT: Enzymatic crosslinking of proteins is often limited by the steric availability of the target residues, as of tyrosyl side chains in the case of tyrosinase. Carrying an N-terminal peptide-tag containing two tyrosine residues, the fluorescent protein C-phycocyanin HisCPC from Synechocystis sp. PCC6803 was crosslinked to fluorescent high-molecular weight forms with tyrosinase. Crosslinking with tyrosinase in the presence of L-tyrosine produced non fluorescent high-molecular weight products. Incubated in the presence of tyrosinase, HisCPC could also be immobilized to amino-modified polystyrene beads thus conferring a blue fluorescence. Crosslinking and immobilization were site-specific as both processes required the presence of the N-terminal peptide in HisCPC.

SUBMITTER: Faccio G

PROVIDER: S-EPMC4064347 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Tyrosinase-catalyzed site-specific immobilization of engineered C-phycocyanin to surface.

Faccio Greta G Kämpf Michael M MM Piatti Chiara C Thöny-Meyer Linda L Richter Michael M

Scientific reports 20140620

Enzymatic crosslinking of proteins is often limited by the steric availability of the target residues, as of tyrosyl side chains in the case of tyrosinase. Carrying an N-terminal peptide-tag containing two tyrosine residues, the fluorescent protein C-phycocyanin HisCPC from Synechocystis sp. PCC6803 was crosslinked to fluorescent high-molecular weight forms with tyrosinase. Crosslinking with tyrosinase in the presence of L-tyrosine produced non fluorescent high-molecular weight products. Incubat ...[more]

PMID: 24947668

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