Insertion and folding of integral membrane proteins into lipid bilayers - Effects of YaeT and membrane-anchored lipoproteins on membrane-protein folding

Details zum Projekt
Projektlaufzeit: 20082014

Insertion and folding of transmembrane proteins are not well understood, although this process is important for membrane biogenesis and cell growth. Gene deletion studies with Gram-negative bacteria recently indicated that the transmembrane protein YaeT (Omp85) and membraneanchored lipoproteins are required for the assembly of outer membrane proteins (OMPs) after they have crossed the periplasm in unfolded form. YaeT and the lipoprotein YfiO are essential in Escherichia coli. Our previous work on the spontaneous insertion and folding of outer membrane proteins into lipid bilayers forms the basis to examine the functions of YaeT and YfiO in inserting OMPs into lipid membranes. We will isolate YaeT, YfiO and the other lipoproteins of the YaeT complex (YfgL, NlpB, and SmpA) to examine their physical properties and their functions in lipid bilayers. In kinetic studies, we will investigate whether YaeT and YfiO facilitate membrane insertion and folding of OMPs like OmpA and OmpG. We will examine the mechanism of OmpA folding into bilayers containing YaeT by site-directed labeling and by a range of spectroscopic methods. This approach will also be used to investigate interactions between YaeT and lipoproteins like YfiO within the YaeT complex and the role of membraneanchored lipoproteins in membrane protein folding.


Zuletzt aktualisiert 2017-11-07 um 13:43