Record Details

Leishmania Major Ascorbate Peroxidase Overexpression Protects Cells Against Reactive Oxygen Species-Mediated Cardiolipin Oxidation

EPrints@IICB

View Archive Info
 
 
Field Value
 
Title Leishmania Major Ascorbate Peroxidase Overexpression Protects Cells Against Reactive Oxygen Species-Mediated Cardiolipin Oxidation
 
Creator Dolai, Subhankar
Yadav, Rajesh K
Pal, Swati
Adak, Subrata
 
Subject Structural Biology & Bioinformatics
 
Description Heme peroxidases are a class of multifunctional redox-active proteins found in all organisms. We recently
cloned, expressed, and characterized an ascorbate peroxidase from Leishmania major (LmAPX) that was
capable of detoxifying hydrogen peroxide. Localization studies using green fluorescent protein fusions
revealed that LmAPX was localized within the mitochondria by its N-terminal signal sequence. Subcellular
fractionation analysis of the cell homogenate by the Percoll density-gradient method and subsequentWestern
blot analysis with anti-LmAPX antibody further confirmed the mitochondrial localization of mature LmAPX.
Submitochondrial fractionation analysis showed that the mature enzyme (∼3.6 kDa shorter than the
theoretical value of the whole gene) was present in the intermembrane space side of the inner membrane.
Moreover, expression of the LmAPX gene was increased by treatment with exogenous H2O2, indicating that
LmAPX was induced by oxidative stress. To investigate the biological role of LmAPX we generated Leishmania
cells overexpressing LmAPX in the mitochondria. Flow-cytometric analysis, thin-layer chromatography, and
IC50 measurements suggested that overexpression of LmAPX caused depletion of the mitochondrial ROS
burden and conferred a protection against mitochondrial cardiolipin oxidation and increased tolerance to
H2O2. These results suggest that the single-copy LmAPX gene plays a protective role against oxidative damage.
© 2008 Elsevier Inc. All rights reserved.
 
Date 2008
 
Type Article
PeerReviewed
 
Format application/pdf
 
Identifier http://www.eprints.iicb.res.in/1054/1/frbm2008.pdf
Dolai, Subhankar and Yadav, Rajesh K and Pal, Swati and Adak, Subrata (2008) Leishmania Major Ascorbate Peroxidase Overexpression Protects Cells Against Reactive Oxygen Species-Mediated Cardiolipin Oxidation. Free Radical Biology & Medicine, 45. pp. 1520-1529.
 
Relation http://dx.doi.org/10.1016/j.freeradbiomed.2008.08.029
http://www.eprints.iicb.res.in/1054/