1kx9
ANTENNAL CHEMOSENSORY PROTEIN A6 FROM THE MOTH MAMESTRA BRASSICAE
|
OverviewOverview
Chemosensory proteins (CSPs) are believed to be involved in chemical, communication and perception. Such proteins, of M(r) 13,000, have been, isolated from several sensory organs of a wide range of insect species., Several CSPs have been identified in the antennae and proboscis of the, moth Mamestra brassicae. One of them, CSPMbraA6, a 112-amino acid antennal, protein, has been expressed in large quantities and is soluble in the, Escherichia coli periplasm. X-ray structure determination has been, performed in parallel with ligand binding assays using tryptophan, fluorescence quenching. The protein has overall dimensions of 25 x 30 x 32, A and exhibits a novel type of alpha-helical fold with six helices, connected by alpha-alpha loops. A narrow channel extends within the, protein hydrophobic core. Fluorescence quenching with brominated alkyl, alcohols or fatty acids and modeling studies indicates that CSPMbraA6 is, able to bind such compounds with C12-18 alkyl chains. These ubiquitous, proteins might have the role of extracting hydrophobic linear compounds, (pheromones, odors, or fatty acids) dispersed in the phospholipid membrane, and transporting them to their receptor.
About this StructureAbout this Structure
1KX9 is a Single protein structure of sequence from Mamestra brassicae with ACT as ligand. Full crystallographic information is available from OCA.
ReferenceReference
X-ray structure and ligand binding study of a moth chemosensory protein., Lartigue A, Campanacci V, Roussel A, Larsson AM, Jones TA, Tegoni M, Cambillau C, J Biol Chem. 2002 Aug 30;277(35):32094-8. Epub 2002 Jun 14. PMID:12068017
Page seeded by OCA on Sun Nov 25 02:07:31 2007