The structure of membrane proteins under solution conditions

All living cells are covered by membrane, which is made up of lipids (fat like molecule) and proteins. Ions like sodium or magnesium are transported across the membrane by proteins in the membrane. Cell membranes and their membrane proteins hold important keys to both present and future medicine. However, it remains a challenge to obtain sufficient structural information about the systems to resolve their function and develop means of pharmaceutical targeting.

The systems are multicomponent by nature, and the interactions between the protein, membrane and the surrounding water phase are crucial for the function but very poorly understood. In the present project we will combine neutron and X-ray scattering to investigate specific examples of such systems. This combination of methods and the contrast variation it allows for, has the potential of providing unique knowledge about these systems.

The central target that we will investigate is the magnesium transporter A (MgtA). Bacteria have always been a part of human life. The bacteria E. coli in our gut needs magnesium, just like humans do. To take up magnesium, E. coli has to two separate protein systems, one functioning at high levels of magnesium and one at low levels of magnesium.

The latter system is called magnesium transporter A (MgtA). The MgtA protein moves magnesium into E.coli. We do, however, not know how the protein looks (structure), and thus lack the molecular understanding needed to design molecules that boost or stop this protein's function.