Multidomain human peroxidasin 1 is a highly glycosylated and stable homotrimeric high spin ferric peroxidase.
J Biol Chem
; 290(17): 10876-90, 2015 Apr 24.
Article
em En
| MEDLINE
| ID: mdl-25713063
ABSTRACT
Human peroxidasin 1 (hsPxd01) is a multidomain heme peroxidase that uses bromide as a cofactor for the formation of sulfilimine cross-links. The latter confers critical structural reinforcement to collagen IV scaffolds. Here, hsPxd01 and various truncated variants lacking nonenzymatic domains were recombinantly expressed in HEK cell lines. The N-glycosylation site occupancy and disulfide pattern, the oligomeric structure, and unfolding pathway are reported. The homotrimeric iron protein contains a covalently bound ferric high spin heme per subunit with a standard reduction potential of the Fe(III)/Fe(II) couple of -233 ± 5 mV at pH 7.0. Despite sequence homology at the active site and biophysical properties similar to human peroxidases, the catalytic efficiency of bromide oxidation (kcat/KM(app)) of full-length hsPxd01 is rather low but increased upon truncation. This is discussed with respect to its structure and proposed biosynthetic function in collagen IV cross-linking.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Receptores de Interleucina-1
/
Colágeno Tipo IV
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Ferro
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Antígenos de Neoplasias
Limite:
Humans
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article