1N8U

Chemosensory Protein in Complex with bromo-dodecanol

Summary for 1N8U

• Entry DOI: 10.2210/pdb1n8u/pdb
• Related: 1K19 1KX8 1KX9 1N8V
• Descriptor: chemosensory protein, BROMO-DODECANOL (3 entities in total)
• Functional Keywords: lipid binding protein
• Biological source: Mamestra brassicae (cabbage moth)
• Total number of polymer chains: 1
• Total formula weight: 13890.53

Authors

Campanacci, V.,Lartigue, A.,Hallberg, B.M.,Jones, T.A.,Giudici-Orticoni, M.T.,Tegoni, M.,Cambillau, C. (deposition date: 2002-11-21, release date: 2003-04-01, Last modification date: 2024-10-30)

Primary citation

Campanacci, V.,Lartigue, A.,Hallberg, B.M.,Jones, T.A.,Giudici-Orticoni, M.T.,Tegoni, M.,Cambillau, C.
Moth chemosensory protein exhibits drastic conformational changes and cooperativity on ligand binding.
Proc.Natl.Acad.Sci.USA, 100:5069-5074, 2003

PubMed Abstract: Chemosensory proteins (CSPs) have been proposed to transport hydrophobic chemicals from air to olfactory or taste receptors. They have been isolated from several sensory organs of a wide range of insect species. The x-ray structure of CSPMbraA6, a 112-aa antennal protein from the moth Mamestra brassicae (Mbra), was shown to exhibit a novel type of alpha-helical fold. We have performed a structural and binding study of CSPMbraA6 to get some insights into its possible molecular function. Tryptophan fluorescence quenching demonstrates the ability of CSPMbraA6 to bind several types of semio-chemicals or surrogate ligands with microM K(d). Its crystal structure in complex with one of these compounds, 12-bromo-dodecanol, reveals extensive conformational changes on binding, resulting in the formation of a large cavity filled by three ligand molecules. Furthermore, binding cooperativity was demonstrated for some ligands, suggesting a stepwise binding. The peculiar rearrangement of CSPMbraA6 conformation and the cooperativity phenomenon might trigger the recognition of chemicals by receptors and induce subsequent signal transduction.

PubMed: 12697900
DOI: 10.1073/pnas.0836654100

Experimental method

X-RAY DIFFRACTION (1.8 Å)