Construction of a Single Chain Variable Fragment Antibody Against Sulfonamides and Its Interaction with Sulfathiazole / 分析化学

ABSTRACT

The interaction between the antibody and the corresponding target molecule determines the characteristics of immunoassay. In this study, a single chain variable fragment antibody (scFv4C7) derived from the hybridoma strain 4C7 were prepared via genetic engineering technique. The recognition properties of scFv4 C7 was determined and compared to those of the parent monoclonal antibody by indirect competitive enzyme-linked immunosorbent assay(ic-ELISA). Three dimensional structure of the scFv4C7 was presented by Swiss-Model, and sulfathiazole ( STZ) was docked to the scFv4C7 model to obtain the structure of the binding complex. The results from the ic-ELISA showed that the binding properties of scFv4C7 were comparable with the parent monoclonal antibody and STZ was almost completely buried in a deep binding pocket formed by the heavy chain and light chain of the antibody. The interaction between STZ and scFv4C7 was more closely related to the heavy chain and the complementarity-determining region ( CDR ) H3 loop played more important role than other CDR loops. The study preliminary provided the necessary structural information for the preparation of antibody with broader specificity and higher affinity.