1RJL

Structure of the complex between OspB-CT and bactericidal Fab-H6831

Summary for 1RJL

• Entry DOI: 10.2210/pdb1rjl/pdb
• Related: 1FJ1 1OSP 1P4P
• Descriptor: Fab H6831 L-chain, Fab H6831 H-chain, Outer surface protein B, ... (5 entities in total)
• Functional Keywords: beta sheet, antibody-protein complex, immune system
• Biological source: Borrelia burgdorferi (Lyme disease spirochete); More
• Cellular location: Cell outer membrane; Lipid-anchor: P17739
• Total number of polymer chains: 4
• Total formula weight: 57632.18

Authors

Becker, M.,Bunikis, J.,Lade, B.D.,Dunn, J.J.,Barbour, A.G.,Lawson, C.L. (deposition date: 2003-11-19, release date: 2004-11-30, Last modification date: 2024-11-20)

Primary citation

Becker, M.,Bunikis, J.,Lade, B.D.,Dunn, J.J.,Barbour, A.G.,Lawson, C.L.
Structural Investigation of Borrelia burgdorferi OspB, a BactericidalFab Target.
J.Biol.Chem., 280:17363-17370, 2005

PubMed Abstract: Certain antibody Fab fragments directed against the C terminus of outer surface protein B (OspB), a major lipoprotein of the Lyme disease spirochete, Borrelia burgdorferi, have the unusual property of being bactericidal even in the absence of complement. We report here x-ray crystal structures of a C-terminal fragment of B. burgdorferi OspB, which spans residues 152-296, alone at 2.0-A resolution, and in a complex with the bactericidal Fab H6831 at 2.6-A resolution. The H6831 epitope is topologically analogous to the LA-2 epitope of OspA and is centered around OspB Lys-253, a residue essential for H6831 recognition. A beta-sheet present in the free OspB fragment is either disordered or removed by proteolysis in the H6831-bound complex. Other conformational changes between free and H6831-bound structures are minor and appear to be related to this loss. In both crystal structures, OspB C-terminal fragments form artificial dimers connected by intermolecular beta-sheets. OspB structure, stability, and possible mechanisms of killing by H6831 and other bactericidal Fabs are discussed in light of the structural data.

PubMed: 15713683
DOI: 10.1074/jbc.M412842200

Experimental method

X-RAY DIFFRACTION (2.6 Å)