NMR Structure Determination of a Membrane Protein with Two Transmembrane Helices in Micelles: MerF of the Bacterial Mercury Detoxification System,
- 11 March 2005
- journal article
- research article
- Published by American Chemical Society (ACS) in Biochemistry
- Vol. 44 (13), 5196-5206
- https://doi.org/10.1021/bi048095v
Abstract
The three-dimensional backbone structure of a membrane protein with two transmembrane helices in micelles was determined using solution NMR methods that rely on the measurement of backbone (1)H-(15)N residual dipolar couplings (RDCs) from samples of two different constructs that align differently in stressed polyacrylamide gels. Dipolar wave fitting to the (1)H-(15)N RDCs determines the helical boundaries based on periodicity and was utilized in the generation of supplemental dihedral restraints for the helical segments. The (1)H-(15)N RDCs and supplemental dihedral restraints enable the determination of the structure of the helix-loop-helix core domain of the mercury transport membrane protein MerF with a backbone RMSD of 0.58 A. Moreover, the fold of this polypeptide demonstrates that the two vicinal pairs of cysteine residues, shown to be involved in the transport of Hg(II) across the membrane, are exposed to the cytoplasm. This finding differs from earlier structural and mechanistic models that were based primarily on the somewhat atypical hydropathy plot for MerF and related transport proteins.Keywords
This publication has 41 references indexed in Scilit:
- Structural features of transmembrane helicesFEBS Letters, 2004
- MerF is a mercury transport protein: different structures but a common mechanism for mercuric ion transporters?FEBS Letters, 2000
- Improving the Packing and Accuracy of NMR Structures with a Pseudopotential for the Radius of GyrationJournal of the American Chemical Society, 1999
- Solution structure of the M13 major coat protein in detergent micelles: a basis for a model of phage assembly involving specific residues 1 † 1Edited by P. E. Wright †The coordinates of the 25 structures of the protein in both micellar systems have been deposited with the Brookhaven Protein Data Bank, along with the related NMR constraints. Entry codes are 2CPB, R2CPBMR (DodPCho) and 2CPS, R2CPSMR (SDS), respectively.Journal of Molecular Biology, 1998
- Helix packing in membrane proteinsJournal of Molecular Biology, 1997
- fd coat protein structure in membrane environments: structural dynamics of the loop between the hydrophobic trans-membrane helix and the amphipathic in-plane helixJournal of Molecular Biology, 1997
- MONSSTER: a method for folding globular proteins with a small number of distance restraintsJournal of Molecular Biology, 1997
- NMRPipe: A multidimensional spectral processing system based on UNIX pipesJournal of Biomolecular NMR, 1995
- The role of cysteine residues in the transport of mercuric ions by the Tn501 MerT and MerP mercury‐resistance proteinsMolecular Microbiology, 1995
- NMR of fd coat proteinJournal of Supramolecular Structure, 1979