2AVI

THREE-DIMENSIONAL STRUCTURES OF AVIDIN AND THE AVIDIN-BIOTIN COMPLEX

Summary for 2AVI

• Entry DOI: 10.2210/pdb2avi/pdb
• Descriptor: AVIDIN, 2-acetamido-2-deoxy-beta-D-glucopyranose, BIOTIN, ... (4 entities in total)
• Functional Keywords: biotin binding protein
• Biological source: Gallus gallus (chicken)
• Cellular location: Secreted: P02701
• Total number of polymer chains: 2
• Total formula weight: 29631.20

Authors

Livnah, O.,Sussman, J. (deposition date: 1993-04-23, release date: 1993-07-15, Last modification date: 2024-10-23)

Primary citation

Livnah, O.,Bayer, E.A.,Wilchek, M.,Sussman, J.L.
Three-dimensional structures of avidin and the avidin-biotin complex.
Proc.Natl.Acad.Sci.USA, 90:5076-5080, 1993

PubMed Abstract: The crystal structures of a deglycosylated form of the egg-white glycoprotein avidin and of its complex with biotin have been determined to 2.6 and 3.0 A, respectively. The structures reveal the amino acid residues critical for stabilization of the tetrameric assembly and for the exceptionally tight binding of biotin. Each monomer is an eight-stranded antiparallel beta-barrel, remarkably similar to that of the genetically distinct bacterial analog streptavidin. As in streptavidin, binding of biotin involves a highly stabilized network of polar and hydrophobic interactions. There are, however, some differences. The presence of additional hydrophobic and hydrophilic groups in the binding site of avidin (which are missing in streptavidin) may account for its higher affinity constant. Two amino acid substitutions are proposed to be responsible for its susceptibility to denaturation relative to streptavidin. Unexpectedly, a residual N-acetylglucosamine moiety was detected in the deglycosylated avidin monomer by difference Fourier synthesis.

PubMed: 8506353
DOI: 10.1073/pnas.90.11.5076

Experimental method

X-RAY DIFFRACTION (3 Å)