Oxidation of Recombinant Human Interleukin-2 by Potassium Peroxodisulfate |
| |
Authors: | Cadée Jenny A van Steenbergen Mies J Versluis Cees Heck Albert J R Underberg Willy J M den Otter Willem Jiskoot Wim Hennink Wim E |
| |
Institution: | (1) Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht, The Netherlands;(2) Department of Biomolecular Mass Spectrometry, UIPS and Bijvoet Center for Biomolecular Research, Utrecht, The Netherlands;(3) Department of Biomedical Analysis, UIPS, Utrecht University, Utrecht, The Netherlands;(4) Department of Biochemistry, Cell Biology and Histology, Utrecht University, Utrecht, The Netherlands;(5) Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht, The Netherlands |
| |
Abstract: | Purpose. The oxidation of recombinant human interleukin-2 (rhIL-2) by potassium peroxodisulfate (KPS) with or without N,N,N ,N -tetramethylethylenediamine (TEMED), which are used for the preparation of dextran-based hydrogels, was investigated.
Methods. The oxidation of (derivatives of) methionine, tryptophan, histidine and tyrosine, as well as rhIL-2 was investigated. Both the oxidation kinetics (RP-HPLC) and the nature of the oxidation products (mass spectrometry) were studied as a function of the KPS and TEMED concentration, and the presence of a competitive antioxidant, methionine.
Results. Under conditions relevant for the preparation of rhIL-2 loaded hydrogels, only methionine and tryptophan derivatives were susceptible to oxidation by KPS. The oxidation of these compounds was inhibited once TEMED was present, suggesting that the peroxodisulfate anion, rather than the radicals formed in the presence of TEMED, is the oxidative species. KPS only induced oxidation of the four methionines present in rhIL-2, whereas the tryptophan residue remained unaffected. The radicals, formed after KPS decomposition by TEMED, induced some dimerization of rhIL-2. The oxidation of rhIL-2 could be substantially reduced by the addition of methionine, or by pre-incubation of KPS with TEMED.
Conclusions. Only the methionine residues in rhIL-2 are oxidized by KPS. The extent of oxidation can be minimized by a proper selection of the reaction conditions. |
| |
Keywords: | oxidation interleukin-2 methionine peroxodisulfate mass spectrometry |
本文献已被 SpringerLink 等数据库收录! |
|