Staff Members of the Institute of Biochemistry, TU - Institut für ...

discovering novel genes, processes and pathways that regulate lipid homeostasis in humans,
mice and yeast. This is one of the projects in the field of functional genomics (GEN-
AU,GENome research in AUstria) funded by the Austrian Federal Ministry for Education,
Science and Culture (bm:bwk).
Green: wt Red: ko Red: wt Green: ko
30
DABGE Analysis of
lipases and esterases
in mouse adipose tissue
of wt and lipase ko mice
Differential activity-based gel electrophoresis (DABGE) was developed for comparative
analysis of two lipolytic proteomes in one polyacrylamide gel. For this purpose, the active
lipases/esterases of two different samples are labelled with fluorescent inhibitors that possess
identical substrate analogous structures but carry different cyanine dyes as reporter
fluorophores. After sample mixing and protein separation by 1-D or 2-D PAGE, the enzymes
carrying the sample-specific colors are detected and quantified. This technique can be used
for the determination of differences in enzyme patterns, e.g. due to effects of genetic
background, environment, metabolic state and disease.
Doctoral Thesis completed:
Ute Stemmer: Toxicity, uptake and targeting of oxidized phospholipids in cultured
macrophages.
The uptake of oxidized low-density lipoprotein (oxLDL) by the macrophages of the arterial
wall and the accumulation of apoptotic cells in atherosclerotic lesions are hallmarks of
atherosclerosis. The harmful effects of oxLDL are largely mediated by the intrinsic toxicity of
a great variety of lipid oxidation products that are generated in LDL under the conditions of
oxidative stress. These compounds comprise oxidized sterols, oxidized fatty acid derivatives
and oxidized glycerophospholipids. Oxidized phospholipids may contain a modified longchain
carboxylic acid or a truncated acyl residue with a polar functional group at its ω-end.
Typical derivatives of truncated phospholipids are the carboxy-phospholipid 1-palmitoyl-2glutaroyl-sn-glycero-3-phosphocholine
(PGPC) and the chemically reactive aldehydophosphospholipid
1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC),
which are oxidation products of arachidonoyl-phosphatidylcholine. The latter lipid can
undergo Schiff base formation with amino groups of proteins, thereby modulating their
properties and functions. It was the aim of the first part of this doctoral thesis to find out