4G0S

Crystal Structure of Epiphyas postvittana Takeout 1 expressed in Sf9 cells

Summary for 4G0S

• Entry DOI: 10.2210/pdb4g0s/pdb
• Related: 3E8T 3E8W
• Descriptor: Takeout-like protein 1, MYRISTIC ACID (3 entities in total)
• Functional Keywords: transport protein
• Biological source: Epiphyas postvittana (Light brown apple moth)
• Total number of polymer chains: 2
• Total formula weight: 49938.22

Authors

Hamiaux, C.,Baker, E.N.,Newcomb, R.D. (deposition date: 2012-07-10, release date: 2013-05-01, Last modification date: 2024-11-27)

Primary citation

Hamiaux, C.,Basten, L.,Greenwood, D.R.,Baker, E.N.,Newcomb, R.D.
Ligand promiscuity within the internal cavity of Epiphyas postvittana Takeout 1 protein.
J.Struct.Biol., 182:259-263, 2013

PubMed Abstract: Takeout proteins are found across a diverse range of insect species and are thought to be involved in important aspects of insect physiology and behavior. These proteins act as ligand carriers, but the nature of their endogenous ligands remains unknown. The crystal structure of Epiphyas postvittana Takeout 1 (EpTo1), the only structure for any Takeout protein to date, revealed an α/β-wrap fold with a purely hydrophobic internal cavity of tubular shape. When recombinantly expressed in Escherichia coli, we previously showed that a surrogate ubiquinone-8 ligand binds within the internal cavity of EpTo1 with excellent shape complementarity. We have now expressed EpTo1 in an insect cell expression system devoid of ubiquinone-8, and solved its crystal structure at 2.2Å resolution. Using combined information from crystallography and mass spectrometry, we identify a mixture of fatty acid moieties, mostly myristic and palmitic acid, bound inside the EpTo1 cavity, mimicking the structure of the longer ubiquinone-8 compound. No significant alteration of the internal cavity was observed regardless of the bound ligands, ubiquinone-8 or fatty acids, suggesting that the internal cavity of EpTo1 forms a rigid scaffold that imposes strict structural constraints for selectivity and specificity of ligand(s) in vivo.

PubMed: 23563188
DOI: 10.1016/j.jsb.2013.03.013

Experimental method

X-RAY DIFFRACTION (2.191 Å)