2. Academic Validation
  3. Multidomain human peroxidasin 1 is a highly glycosylated and stable homotrimeric high spin ferric peroxidase

Multidomain human peroxidasin 1 is a highly glycosylated and stable homotrimeric high spin ferric peroxidase

  • J Biol Chem. 2015 Apr 24;290(17):10876-90. doi: 10.1074/jbc.M114.632273.
Monika Soudi 1,  Martina Paumann-Page 1,  Cedric Delporte 2,  Katharina F Pirker 1,  Marzia Bellei 3,  Eva Edenhofer 1,  Gerhard Stadlmayr 1,  Gianantonio Battistuzzi 4,  Karim Zouaoui Boudjeltia 5,  Paul G Furtmüller 1,  Pierre Van Antwerpen 2,  Christian Obinger 6
Affiliations

Affiliations

  • 1 From the Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria.
  • 2 the Laboratory of Pharmaceutical Chemistry and Analytical Platform of the Faculty of Pharmacy, Faculty of Pharmacy, Université Libre de Bruxelles, 1050 Brussels, Belgium.
  • 3 the Departments of Life Sciences and.
  • 4 Chemistry and Geology, University of Modena and Reggio Emilia, 41125 Modena, Italy, and.
  • 5 the Laboratory of Experimental Medicine (ULB 222 Unit), CHU de Charleroi, A. Vésale Hospital, Université Libre de Bruxelles, 6110 Montigny-le-Tilleul, Belgium.
  • 6 From the Department of Chemistry, Division of Biochemistry, BOKU-University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria, christian.obinger@boku.ac.at.
PMID: 25713063 DOI: 10.1074/jbc.M114.632273
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.

Keywords

Collagen; Extracellular Matrix Protein; Glycosylation; Metalloenzyme; Peroxidase; Peroxidasin; Vascular Peroxidase.

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