Pressure-stability of phospholipid bicelles Measurement of residual dipolar couplings under extreme conditions

High-pressure NMR of proteins in solutions currently gains increasing inter est. 3D structure determination of proteins under high pressure is, however , so far impossible due to the lack of NOE information. Residual dipolar co uplings induced by the addition of magnetically orienting media are known t o be capable of replacing NOE information to a very high extent. In the pre sent contribution we study the pressure-stability of dimyristoylphosphatidy lcholine (DMPC)/ dihexanoylphosphatidylcholine (DHPC) bicelles and demonstr ate the feasibility of measuring residual dipolar couplings in proteins und er high pressure.