Final Activity Report Summary - MEMPROT (Structural studies of membrane proteases.)
Membrane proteins play essential roles in life: they act as ion channels, ion pumps, signalling centres, proteases, light harvesters in plants, and as the producers of the cellular energy currency ATP in mitochondria. Despite their central importance in all kingdoms of life, and the interest in human membrane proteins as drug targets (up to 50% of all marketed drugs target membrane proteins), the structural and mechanistic understanding of membrane proteins lacks far behind the understanding of their soluble counterparts. This is due to difficulties at all stages in the work with membrane proteins: membrane proteins are more difficult to produce than soluble proteins, require expensive detergents for membrane extraction and purification, and tend to crystallise poorly.
In this project, we have attempted to purify membrane proteins, and particularly membrane proteases, both from natural sources and from genetically modified expression cells. So far, we have been able to grow crystals of one membrane protein complex, the photosystem II from the tobacco plant. This work is described in the publication "Crystallisation of the Photosystem II core complex and its chlorophyll binding subunit CP43 from transplastomic plants of Nicotiana tabacum. Piano D, El Alaoui S, Korza HJ, Filipek R, Sabala I, Haniewicz P, Buechel C, De Sanctis D, Bochtler M., Photosynth Res. 2010 Nov 10, epub ahead of print", which is attached to this report. Crystallisation of the other membrane embedded proteases that we have been able to express is still on-going.
In this project, we have attempted to purify membrane proteins, and particularly membrane proteases, both from natural sources and from genetically modified expression cells. So far, we have been able to grow crystals of one membrane protein complex, the photosystem II from the tobacco plant. This work is described in the publication "Crystallisation of the Photosystem II core complex and its chlorophyll binding subunit CP43 from transplastomic plants of Nicotiana tabacum. Piano D, El Alaoui S, Korza HJ, Filipek R, Sabala I, Haniewicz P, Buechel C, De Sanctis D, Bochtler M., Photosynth Res. 2010 Nov 10, epub ahead of print", which is attached to this report. Crystallisation of the other membrane embedded proteases that we have been able to express is still on-going.