%0 Journal Article
%T The Binding Affinity and Molecular Basis of the Structure-Binding Relationship between Urinary Tamm-Horsfall Glycoprotein and Tumor Necrosis Factor-¦Á
%A Cheng-Han Wu
%A Ko-Jen Li
%A Sue-Cien Siao
%A Yu-Hsuan Chen
%A Tsai-Hung Wu
%A Chang-Youh Tsai
%A Chia-Li Yu
%J Molecules
%D 2012
%I MDPI AG
%R 10.3390/molecules171011978
%X In a previous study we noted significant THP binding to TNF-¦Á, but did not explore the molecular basis of the structure-binding relationship. In this study, we used lectin-binding ELISA to assess the carbohydrate compositions of THP, BSA, IgG, TNF-¦Á, and IFN-g. We identified ¦Â(1,4)-N-acetylglucosamine oligomers (GlcNAc) and GlcNAc/branched mannose in BSA, IgG, TNF-¦Á, and THP, but not in IFN-g. These carbohydrate moieties mediated binding with THP. Small amounts of Sia¦Á(2,3)Gal/ GalNAc, Sia(2,6)Gal/GalNAc, and mannose residues were also present in THP and TNF-¦Á. Binding affinity (Kd) between THP and TNF-¦Á by Scatchard plot analysis was 1.4¨C1.7 ¡Á 10£¿6 M, lower than antigen-antibody or ligand-receptor binding affinities. To elucidate the structure-binding relationship of THP-TNF-¦Á, THP was digested with neuraminidase, ¦Â-galactosidase, O-sialoglycoprotein endopeptidase, carboxypeptidase Y, or proteinase K. ¦Â-galactosidase increased binding capacity of THP for TNF-¦Á. Monosaccharide inhibition suggested that ¦Á-methyl-D-mannoside, GlcNAc, and GalNAc, but not sialic acid, suppress THP-TNF-¦Á binding as detected by ELISA. We conclude that sugar-lectin and sugar-protein interactions between cognate sites in THP and TNF-¦Á mediate their binding.
%K Tamm-Horsfall glycoprotein
%K tumor necrosis factor-¦Á
%K binding affinity
%K structure-binding relationship
%K glucosamine-containing mannose
%U http://www.mdpi.com/1420-3049/17/10/11978