2M67

Full-length mercury transporter protein MerF in lipid bilayer membranes

Summary for 2M67

• Entry DOI: 10.2210/pdb2m67/pdb
• Related: 1WAZ 2H3O 2LJ2
• Descriptor: MerF (1 entity in total)
• Functional Keywords: integral membrane protein, mercury transporter, lipid bilayer, transport protein
• Biological source: Morganella morganii
• Total number of polymer chains: 1
• Total formula weight: 8670.40

Authors

Lu, G.J.,Tian, Y.,Vora, N.,Marassi, F.M.,Opella, S.J. (deposition date: 2013-03-27, release date: 2013-07-03, Last modification date: 2024-05-15)

Primary citation

Lu, G.J.,Tian, Y.,Vora, N.,Marassi, F.M.,Opella, S.J.
The Structure of the Mercury Transporter MerF in Phospholipid Bilayers: A Large Conformational Rearrangement Results from N-Terminal Truncation.
J.Am.Chem.Soc., 135:9299-9302, 2013

PubMed Abstract: The three-dimensional structure of the 81-residue mercury transporter MerF determined in liquid crystalline phospholipid bilayers under physiological conditions by Rotationally Aligned (RA) solid-state NMR has two long helices, which extend well beyond the bilayer, with a well-defined interhelical loop. Truncation of the N-terminal 12 residues, which are mobile and unstructured when the protein is solubilized in micelles, results in a large structural rearrangement of the protein in bilayers. In the full-length protein, the N-terminal helix is aligned nearly parallel to the membrane normal and forms an extension of the first transmembrane helix. By contrast, this helix adopts a perpendicular orientation in the truncated protein. The close spatial proximity of the two Cys-containing metal binding sites in the three-dimensional structure of full-length MerF provides insights into possible transport mechanisms. These results demonstrate that major changes in protein structure can result from differences in amino acid sequence (e.g., full-length vs truncated proteins) as well as the use of a non-native membrane mimetic environment (e.g., micelles) vs liquid crystalline phospholipid bilayers. They provide further evidence of the importance of studying unmodified membrane proteins in near-native bilayer environments in order to obtain accurate structures that can be related to their functions.

PubMed: 23763519
DOI: 10.1021/ja4042115

Experimental method

SOLID-STATE NMR