1B0O

BOVINE BETA-LACTOGLOBULIN COMPLEXED WITH PALMITATE, LATTICE Z

Summary for 1B0O

• Entry DOI: 10.2210/pdb1b0o/pdb
• Descriptor: BETA-LACTOGLOBULIN, PALMITIC ACID (3 entities in total)
• Functional Keywords: lipocalin, milk whey protein, bovine, palmitate-binding
• Biological source: Bos taurus (cattle)
• Total number of polymer chains: 1
• Total formula weight: 18557.60

Authors

Wu, S.-Y.,Sawyer, L. (deposition date: 1998-11-11, release date: 1999-02-02, Last modification date: 2024-10-30)

Primary citation

Wu, S.Y.,Perez, M.D.,Puyol, P.,Sawyer, L.
beta-lactoglobulin binds palmitate within its central cavity.
J.Biol.Chem., 274:170-174, 1999

PubMed Abstract: Bovine beta-lactoglobulin (beta-Lg) has been studied extensively in both the isolated and the naturally occurring states. It is a commercially important whey protein of obvious nutritional value but, so far, one that has no clearly identified biological function. In common with many of the other members of the lipocalin family to which it belongs, beta-Lg binds hydrophobic ligands, and it appears possible that there are at least two distinct binding sites per monomer for a variety of ligands. By comparison with other members of the family, there is a probable binding site in the central cavity of the molecule that is formed by the eight antiparallel beta-strands that are typical of the lipocalins. We have now cocrystallized beta-Lg with palmitic acid, and the refined structure (R = 0.204, Rfree = 0.240 for 6,888 reflections to 2.5-A resolution) reveals that the ligand binds in the central cavity in a manner similar to the binding of retinol to the related lipocalin, serum retinol-binding protein. The carboxyl group binds to both Lys-60 and Lys-69 at the entrance to the cavity. The hydrophobic tail stretches in an almost fully extended conformation into the center of the protein. This is the first direct observation of a ligand binding to beta-Lg.

PubMed: 9867826
DOI: 10.1074/jbc.274.1.170

Experimental method

X-RAY DIFFRACTION (2.5 Å)