Ether cross-link formation in the R2-like ligand-binding oxidase.
J Biol Inorg Chem
; 23(6): 879-886, 2018 08.
Article
em En
| MEDLINE
| ID: mdl-29946980
R2-like ligand-binding oxidases contain a dinuclear metal cofactor which can consist either of two iron ions or one manganese and one iron ion, but the heterodinuclear Mn/Fe cofactor is the preferred assembly in the presence of MnII and FeII in vitro. We have previously shown that both types of cofactor are capable of catalyzing formation of a tyrosine-valine ether cross-link in the protein scaffold. Here we demonstrate that Mn/Fe centers catalyze cross-link formation more efficiently than Fe/Fe centers, indicating that the heterodinuclear cofactor is the biologically relevant one. We further explore the chemical potential of the Mn/Fe cofactor by introducing mutations at the cross-linking valine residue. We find that cross-link formation is possible also to the tertiary beta-carbon in an isoleucine, but not to the secondary beta-carbon or tertiary gamma-carbon in a leucine, nor to the primary beta-carbon of an alanine. These results illustrate that the reactivity of the cofactor is highly specific and directed.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oxirredutases
Idioma:
En
Revista:
J Biol Inorg Chem
Assunto da revista:
BIOQUIMICA
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Suécia