4Q00

Crystal structure of an S150A mutant of the E. coli FeoB G-domain

Summary for 4Q00

• Entry DOI: 10.2210/pdb4q00/pdb
• Related: 3HYR
• Descriptor: Ferrous iron transport protein B, SULFATE ION (3 entities in total)
• Functional Keywords: g protein, iron transport, gtpase, transmembrane, metal transport, gtp binding
• Biological source: Escherichia coli
• Cellular location: Cell inner membrane; Multi-pass membrane protein: P33650
• Total number of polymer chains: 3
• Total formula weight: 86369.67

Authors

Jormakka, M.,Guilfoyle, A.P.,Deshpande, C.N. (deposition date: 2014-03-31, release date: 2015-02-18, Last modification date: 2024-03-20)

Primary citation

Guilfoyle, A.P.,Deshpande, C.N.,Schenk, G.,Maher, M.J.,Jormakka, M.
Exploring the correlation between the sequence composition of the nucleotide binding G5 loop of the FeoB GTPase domain (NFeoB) and intrinsic rate of GDP release.
Biosci.Rep., 34:e00158-e00158, 2014

PubMed Abstract: GDP release from GTPases is usually extremely slow and is in general assisted by external factors, such as association with guanine exchange factors or membrane-embedded GPCRs (G protein-coupled receptors), which accelerate the release of GDP by several orders of magnitude. Intrinsic factors can also play a significant role; a single amino acid substitution in one of the guanine nucleotide recognition motifs, G5, results in a drastically altered GDP release rate, indicating that the sequence composition of this motif plays an important role in spontaneous GDP release. In the present study, we used the GTPase domain from EcNFeoB (Escherichia coli FeoB) as a model and applied biochemical and structural approaches to evaluate the role of all the individual residues in the G5 loop. Our study confirms that several of the residues in the G5 motif have an important role in the intrinsic affinity and release of GDP. In particular, a T151A mutant (third residue of the G5 loop) leads to a reduced nucleotide affinity and provokes a drastically accelerated dissociation of GDP.

PubMed: 25374115
DOI: 10.1042/BSR20140152

Experimental method

X-RAY DIFFRACTION (2.1 Å)