S1
Supporting Information
Subtle changes in the combining site of the Chlamydiaceae-specific mAb
S25-23 increase antibody-carbohydrate binding affinity by an order of magnitude*
Omid Haji-Ghassemi1‡, Sven Müller-Loennies2†, Cory L. Brooks3, C. Roger MacKenzie4, Nathanael Caveney1, Filip Van Petegem5, Lore Brade2, Paul Kosma5, Helmut Brade2, Stephen V. Evans1†
1 Department of Biochemistry and Microbiology, University of Victoria, PO Box 3055 STN CSC, Victoria, BC, Canada V8P 3P6; 2 Research Center Borstel, Leibniz Lung Center, Parkallee 22, Borstel D-23845, Germany; 3 Department of Chemistry, Fresno State University, 2555 E. San Ramon Ave., MS SB70, Fresno, CA 93740; 4 Human Health Therapeutics Portfolio, National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario, Canada, K1A 0R6; 5 Department of Chemistry, University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
S2 Figure S1: Variable light chain DNA sequence alignment of S25-26 and S25-23 mAbs. One
S3 Figure S2: Stereo diagram of 2Fo-Fc and Fo-Fc electron density maps of (A) Arg(L)-27E of S25-26 Fab structure in complex with
αKdo(2→8)αKdo(2→4)αKdo O-allyl trisaccharide (PDB 4M7J). Arg(L)-27E forms a crystal contact with the side chain Glu(H)-195 (yellow). Panels B-D show the Lys(L)-27E residue of S25-23 in complex with PSBP from each crystal form. (B). Depicted from crystal form 1 of S25-23, while (C) and (D), belong to the unique Fabs of crystal form 2. The 2Fo-Fc and Fo-Fc maps were generated after deleting the arginine or lysine side chain, followed by two cycles of refinement in Refmac. 2Fo-Fc maps were contoured to 1.0 σ (blue) for Arg/Lys-L27E residue and adjacent residues, while the Fo-Fc maps were contoured to 2.0 σ (green) and -2.0 (red) within 2 Å of the arginine residue. For clarity, the lipid A moiety is not displayed.
