9INK

Crystal structure of beta-carotene-binding protein (BBP) from Schistocerca gregaria complexed with beta-carotene

Summary for 9INK

• Entry DOI: 10.2210/pdb9ink/pdb
• Descriptor: Yellow protein of the takeout family, BETA-CAROTENE (3 entities in total)
• Functional Keywords: complex with beta-carotene, carotenoprotein, takeout-1 domain, tubular lipid-binding protein (tulips), carotenoid solubilizer, dimer, lipid binding protein
• Biological source: Schistocerca gregaria
• Total number of polymer chains: 2
• Total formula weight: 53553.37

Authors

Boyko, K.M.,Varfolomeeva, L.A.,Egorkin, N.A.,Popov, V.O.,Sluchanko, N.N. (deposition date: 2024-07-08, release date: 2024-09-18, Last modification date: 2024-12-18)

Primary citation

Egorkin, N.A.,Dominnik, E.E.,Raevskii, R.I.,Kuklina, D.D.,Varfolomeeva, L.A.,Popov, V.O.,Boyko, K.M.,Sluchanko, N.N.
Structural basis of selective beta-carotene binding by a soluble protein.
Structure, 32:2123-2133.e3, 2024

PubMed Abstract: β-carotene (BCR) is the most abundant carotenoid, a colorant, antioxidant, and provitamin A. The extreme hydrophobicity of this hydrocarbon requires special mechanisms for distribution in aqueous media, including water-soluble carotenoproteins. However, all known carotenoproteins prefer oxygenated carotenoids and bind BCR inefficiently. Here, we present the crystal structure of the BCR-binding protein (BBP) from gregarious male locusts, which is responsible for their vivid yellow body coloration, in complex with its natural ligand, BCR. BBP forms an antiparallel tubular homodimer with α/β-wrap folded monomers, each forming a hydrophobic 47 Å long, coaxial tunnel that opens outward and is occupied by one s-cis, all-trans BCR molecule. In the BCR absence, BBP accepts a range of xanthophylls, with reduced efficiency depending on the position and number of oxygen atoms, but rejects lycopene. The structure captures a pigment complex with a Takeout 1 protein and inspires potential applications of BBP as a BCR solubilizer.

PubMed: 39383875
DOI: 10.1016/j.str.2024.09.014

Experimental method

X-RAY DIFFRACTION (2.7 Å)