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Oxidized von Willebrand factor is efficiently cleaved by serine proteases from primary granules of leukocytes: divergence from ADAMTS-13.
- Source :
-
Journal of thrombosis and haemostasis : JTH [J Thromb Haemost] 2011 Aug; Vol. 9 (8), pp. 1620-7. - Publication Year :
- 2011
-
Abstract
- Background: The leukocyte serine proteases (LSPs) elastase, proteinase 3 and cathepsin G cleave von Willebrand factor (VWF) near or at the same cleavage site (Tyr1605-Met1606) as ADAMTS-13, the metalloprotease that specifically controls the proteolytic processing of VWF. Recent studies have shown that oxidation of VWF at Met1606 with formation of methionine sulfoxide (MetSO) severely impairs its proteolysis by ADAMTS-13.<br />Methods: This study was aimed at assessing whether or not oxidation of VWF by reactive oxygen species (ROS) can also affect its cleavage by elastase, proteinase 3, and cathepsin G. In this study, the catalytic specificity of hydrolysis by LSPs of the VWF peptide substrate VWF74 and full-length VWF, both unaltered and in the oxidized form, was measured by RP-HPLC, electrophoretic and mass spectrometry methods.<br />Results: LSPs cleaved both VWF multimers and VWF74 near or at the same peptide bond as is cleaved by ADAMTS-13, with k(cat)/K(m) values similar to those of the metalloprotease. However, unlike ADAMTS-13, cathepsin G cleaved VWF74 containing a MetSO residue at position 1606 with a k(cat)/K(m) value higher than that for VWF74, whereas the catalytic efficiencies of both elastase and proteinase 3 were unaffected by the replacement of Met1606 with MetSO. Likewise, oxidation of VWF multimers by hypochlorous acid and ROS, produced by activated leukocytes, improved their hydrolysis by LSPs.<br />Conclusions: Oxidation by leukocyte ROS has a net positive effect on the cleavage of VWF multimers by LSPs, under conditions where high concentrations of oxidant species would severely reduce the proteolytic efficiency of ADAMTS-13.<br /> (© 2011 International Society on Thrombosis and Haemostasis.)
- Subjects :
- ADAMTS13 Protein
Amino Acid Sequence
Cathepsin G metabolism
Chromatography, High Pressure Liquid
Chromatography, Reverse-Phase
Circular Dichroism
Electrophoresis, Agar Gel
Humans
Hydrolysis
Kinetics
Leukocyte Elastase metabolism
Mass Spectrometry
Molecular Sequence Data
Myeloblastin metabolism
Oxidation-Reduction
Protein Multimerization
Reactive Oxygen Species metabolism
Spectrometry, Fluorescence
Spectrophotometry, Ultraviolet
von Willebrand Factor chemistry
ADAM Proteins metabolism
Cytoplasmic Granules enzymology
Leukocytes enzymology
Protein Processing, Post-Translational
Serine Proteases metabolism
von Willebrand Factor metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 1538-7836
- Volume :
- 9
- Issue :
- 8
- Database :
- MEDLINE
- Journal :
- Journal of thrombosis and haemostasis : JTH
- Publication Type :
- Academic Journal
- Accession number :
- 21605335
- Full Text :
- https://doi.org/10.1111/j.1538-7836.2011.04367.x