J Michael Sauder - Structural studies on cytosolic domain of magnesium transporter MgtE from Enterococcus faecalis

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      Publication Details (including relevant citation   information):

      Proteins (2010) 78: 487-491.

      Ragumani S, Sauder JM, Burley SK, Swaminathan S

      Abstract:

      Magnesium (Mg2+) is an essential element for growth and   maintenance of living cells. It acts as a cofactor for many   enzymes and is also essential for stability of the plasma   membrane. There are two distinct classes of magnesium   transporters identified in bacteria that convey Mg2+ from   periplasm to cytoplasm [ATPase-dependent (MgtA and MgtB) and   constitutively active (CorA and MgtE)]. Previously published work   on Mg(2+) transporters yielded structures of full length MgtE   from Thermus thermophilus,  determined at 3.5 Å resolution,   and its cytoplasmic domain with and without bound Mg2+ determined   at 2.3 and 3.9 Å resolution, respectively [Hattori, 2007]. Here,   we report the crystal structure of the Mg(2+) bound form of the   cytosolic portion of MgtE (residues 6-262) from Enterococcus   faecalis at 2.2 Å resolution. The present structure and   magnesium bound cytosolic domain structure from T.   thermophilus (PDB ID: 2YVY) are structurally similar. Three   magnesium binding sites are common to both MgtE full length and   the present structure. Our work revealed an additional Mg(2+)   binding site in the E. faecalis structure. In this report, we   discuss the functional significance of Mg(2+) binding sites in   the cytosolic domains of MgtE transporters.

      Address (URL): http://www.ncbi.nlm.nih.gov/pubmed/19787770