1c3y
From Proteopedia
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THP12-CARRIER PROTEIN FROM YELLOW MEAL WORM
Overview
BACKGROUND: THP12 is an abundant and extraordinarily hydrophilic hemolymph, protein from the mealworm Tenebrio molitor and belongs to a group of small, insect proteins with four highly conserved cysteine residues. Despite, their sequence homology to odorant-binding proteins and pheromone-binding, proteins, the function of these proteins is unclear. RESULTS: The first, three-dimensional structure of THP12 has been determined by, multidimensional NMR spectroscopy. The protein has a nonbundle helical, structure consisting of six alpha helices. The arrangement of the alpha, helices has a 'baseball glove' shape. In addition to the hydrophobic core, electrostatic interactions make contributions to the overall stability of, the protein. NMR binding studies demonstrated the binding of small, hydrophobic ligands to the single hydrophobic groove in THP12. Comparing, the structure of THP12 with the predicted secondary structure of homologs, reveals a common fold for this new class of insect proteins. A search with, the program DALI revealed extensive similarity between the, three-dimensional structure of THP12 and the N-terminal domain (residues, 1-95) of recoverin, a member of the family of calcium-binding EF-hand, proteins. CONCLUSIONS: Although the biological function of this new class, of proteins is as yet undetermined, a general role as alpha-helical, carrier proteins for small hydrophobic ligands, such as fatty acids or, pheromones, is proposed on the basis of NMR-shift perturbation, spectroscopy.
About this Structure
1C3Y is a Single protein structure of sequence from Tenebrio molitor. Full crystallographic information is available from OCA.
Reference
A new class of hexahelical insect proteins revealed as putative carriers of small hydrophobic ligands., Rothemund S, Liou YC, Davies PL, Krause E, Sonnichsen FD, Structure. 1999 Nov 15;7(11):1325-32. PMID:10574794
Page seeded by OCA on Sun Nov 25 01:03:53 2007
