2hn2
Crystal structure of the CorA Mg2+ transporter homologue from T. maritima in complex with divalent cations
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| , resolution 3.700Å | |||||||
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| Ligands: | |||||||
| Gene: | CorA (Thermotoga maritima) | ||||||
| Related: | 2BBJ, 2BBH, 2HN1, 2IUB
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
OverviewOverview
We describe the CorA Mg(2+) transporter homologue from Thermotoga maritima in complex with 12 divalent cations at 3.7 A resolution. One metal is found near the universally conserved GMN motif, apparently stabilized within the transmembrane region. This portion of the selectivity filter might discriminate between the size and preferred coordination geometry of hydrated substrates. CorA may further achieve specificity by requiring the sequential dehydration of substrates along the length of its approximately 55 A long pore. Ten metal sites identified within the cytoplasmic funnel domain are linked to long extensions of the pore helices and regulate the transport status of CorA. We have characterized this region as an intrinsic divalent cation sensor and provide evidence that it functions as a Mg(2+)-specific homeostatic molecular switch. A proteolytic protection assay, biophysical data, and comparison to a soluble domain structure from Archaeoglobus fulgidus have revealed the potential reaction coordinate for this diverse family of transport proteins.
About this StructureAbout this Structure
2HN2 is a Single protein structure of sequence from Thermotoga maritima. Full crystallographic information is available from OCA.
ReferenceReference
A structural basis for Mg2+ homeostasis and the CorA translocation cycle., Payandeh J, Pai EF, EMBO J. 2006 Aug 23;25(16):3762-73. Epub 2006 Aug 10. PMID:16902408
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