Graz University of Technology Austria Institute of Biochemistry ...

Biophysical chemistry group
Group leader: Albin Hermetter
Postdoctoral Fellow: Heidemarie Ehammer
PhD students: Ute Stemmer, Daniel Koller, Claudia Ramprecht, Lingaraju Marlingapla
Halasiddappa, Bojana Stojcic
Master students: Andreas Gasser, Gabriel Pürstinger, Hannah Jaritz
Technicians: Elfriede Zenzmaier
General description
Our research deals with the role of glycero(phospho)lipids and lipid modifying enzymes as
components of membranes and lipoproteins, their function as mediators in cellular
(patho)biochemistry, and their application as analytical tools in enzyme technology.
Fluorescence spectroscopy is used as a main technique to investigate the behaviour of these
biomolecules in the respective supramolecular systems.
Section 1 of the following report summarizes our studies on lipid oxidation, the effects of
oxidized lipids on intracellular signalling, and the inhibition of these processes by synthetic
and natural antioxidants.
Section 2 describes the development of fluorescence for functional proteomic analysis of
lipolytic enzymes in microbial, animal and human cells.
1. Lipid oxidation and atherosclerosis – Lipotoxicity
1.1. Interaction of oxidized phospholipids with vascular cells
Sphingomyelin
acid
Sphingomyelinase
Oxidized -
Phospholipids
O
H
O
O
O
O
O
O
O
O
O
O P O
OH
O
O
O
O P O
OH
+
N
N +
Ceramide
OXPHOS-EuroMEMBRANE
JNK
p38 MAPK
Caspase 3
ERK
AKT/PKB
NFkB
PROLIFERATION
SURVIVAL
Interactions of oxidized lipoproteins with
the cells of the arterial wall induce and
influence the progress of atherosclerosis.
Accumulation of foam cells originating
from macrophages and excessive intimal
growth of vascular smooth muscle cells
(SMC) alternating with focal massive cell
death are characteristics typical of the atherosclerotic lesion. These phenomena are largely
mediated by the oxidized phospholipid components of the modified particles that are
generated under the conditions of oxidative stress. In the framework of the research consortia
LIPOTOX (SFB) and OXPHOS (EuroMEMBRANE), we investigate the “Toxicity of
oxidized phospholipids in macrophages” and “The protein targets and apoptotic signaling of
oxidized phospholipids”. These studies aim at identifying the molecular and cellular effects of
an important subfamily of the oxidized phospholipids containing long hydrocarbon chains in
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