Quantitative evaluation of the role of cysteine and methionine residues in the antioxidant activity of human serum albumin using recombinant mutants |
| |
Authors: | Iwao Yasunori Ishima Yu Yamada Junji Noguchi Taishi Kragh-Hansen Ulrich Mera Katsumi Honda Daisuke Suenaga Ayaka Maruyama Toru Otagiri Masaki |
| |
Affiliation: | Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan. |
| |
Abstract: | The importance of cysteine (Cys) and methionine (Met) residues for the antioxidant activity of human serum albumin (HSA) was investigated using recombinant HSA mutants, in which Cys34 and/or the six Met residues had been mutated to Ala. The scavenging activities of the mutants against five reactive oxygen and nitrogen species were evaluated by a chemiluminescence assay, electron paramagnetic resonance spectroscopy, or a HPLC-flow reactor assay. Our results showed that the contributions of Cys34 and the Met residues to the antioxidant activity of HSA were 61% and 29% against O(2)(?-), 68% and 61% against H(2)O(2), 38% and 6% against HO(?), 36% and 13% against HOCl, and 51% and 1% against (?)NO, respectively. Thus, the findings propose in a direct way that Cys34 plays a more important role than the Met residues in the antioxidant activity of HSA. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|