Abstract
The interfacial behavior differences of two glutathione peroxidase isoforms have been investigated. The first isoform is the phospholipid-hydroperoxide glutathione peroxidase (EC 1.11.1.12) (GPx-4) isolated from rat testes and the second one is the cytosolic glutathione peroxidase (EC 1.11. 1.9) (GPx-1) from bovine erythrocytes. Injected in the subphase buffer of a Langmuir trough, GPx-4 was able to adsorb quickly at the air-water interface whereas the GPx-1 was not. Then, the protein interaction with phospholipid monolayers was explored. Indeed, a monolayer of phospholipids containing a different number of polyunsaturated fatty acyl chains was prepared at the air-water interface. Under each kind of monolayer, the protein solution was injected and its adsorption was visualized by the measurement of successive pressure-area isotherms. We have, then, determined the molecular area increase due to the protein adsorption. It was found that the GPx-4 is adsorbed in each kind of monolayer tested whereas no molecular area increase was detected with the GPx-1. This indicates that the GPx-4 has a higher affinity for the interface, recovered or not by lipids, than the GPx-1. Moreover, the GPx-4 presents a different affinity for the phospholipid monolayers depending on the number of polyunsaturated fatty acyl chains. (C) 2004 Elsevier B.V. All rights reserved.
Original language | English |
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Pages (from-to) | 99-105 |
Number of pages | 7 |
Journal | Colloids and Surfaces. B, Biointerfaces |
Volume | 35 |
Issue number | 2 |
DOIs | |
Publication status | Published - 15 May 2004 |
Keywords
- glutathione peroxidase
- protein adsorption
- protein-lipid interactions
- Langmuir monolayer
- polyunsaturated phospholipids
- bovine serum-albumin
- air/water interface
- beta-lactoglobulin
- mixed monolayers
- membranes
- purification
- lipids