ABSTRACT
The conjugation of active biomolecules provides insight into their bioreactivity, leading to many applications in biotechnology and materials science. Herein, we report L-selenocystine (SeC) bioconjugates of lipoic acid (universal antioxidant) and biotin (Vitamin-H). The SeC-bioconjugates, SeC-Biotin (1) and SeC-Lipoic acid (2) were synthesized using solid phase peptide synthesis (SPPS) method and were characterized by multinuclear 1D (1H, 13C, 77Se) and 2D (1H-1H COSY and 1H-13C TOCSY) NMR spectroscopy, ESI-MS spectrometry, and RP-HPLC. The GPx-like enzyme mimicking activity of the SeC-bioconjugates 1 and 2 has been investigated through the coupled reductase assay method for the catalytic reductions of hydrogen peroxide into water. A significant enhancement in GPx-like enzymatic activity was observed for both novel bioconjugates SeC-Biotin (1) and SeC-Lipoic acid (2) as compared to diphenyl diselenide (Ph2Se2), L-selenocystine (SeC), biotin, lipoic acid, and ebselen.
Subject(s)
Organoselenium Compounds , Thioctic Acid , Thioctic Acid/chemistry , Biotin , Glutathione Peroxidase , Organoselenium Compounds/chemistry , Antioxidants/chemistry , Glutathione/chemistryABSTRACT
A facile general route for the synthesis of various selenocystine tripeptides containing acidic, basic and neutral side chain amino acids is reported. Here, TFA labile side chain protected selenocysteine has been used as a precursor for the synthesis of selenopeptides. The peptides are highly stable in dimethyl sulphoxide, thus enabling detailed NMR studies by solution phase 1- and 2-dimensional NMR spectroscopy.
