Identification of peptide mimotopes for the fluorescein hapten binding of monoclonal antibody B13-DE1

Abstract

Using 6mer and 12mer phage peptide libraries three unique phage clones were identified which specifically bind to a monoclonal anti-FITC antibody, B13-DE1. The two 6mer and one 12mer peptide insert sequences are clearly related to each other and contain a high proportion of hydrophobic amino acids. The peptides are bound by the antibody combining site of B13-DE1 probably in a similar manner to FITC and represent therefore true peptidic mimics of the fluorescein hapten. No reactivity of the peptides could be demonstrated with another monoclonal anti-fluorescein antibody or with polyclonal anti-fluorescein antibodies. Immunization of mice with the peptides resulted in the production of antibodies cross-reacting with all peptides but not with fluorescein. The results show that phage peptide libraries can be used to isolate mimotope peptides which can mimic low molecular weight structures seen by a specific antibody and probably other recognition molecules.

Development of Peptidyl Lysine Dendrons: 1,3‐Dipolar Cycloaddition for Peptide Coupling and Antibody Recognition

“…In the following, a chemoselective strategy employing ‘spring‐loaded’ synthesis partners and exhibiting enhanced binding affinities is presented to obtain and connect biological active peptides with a branched structure. In the literature, the binding affinities of three peptides to the monoclonal antibody B13‐DE1 have been well characterized by ELISA titration test. The selected peptides P1–P3 are illustrated in Figure S1.…”

“…For our investigations, we will implement the peptide mimotopes of the anti‐FITC antibody B13‐DE1. The antibody combining site is sensitive for the fluorescent dye fluorescein and their structural related derivatives as well as for the explored peptides .…”

Oxidoreductase activity of multifunctional monoclonal antibody B13‐DE1

“…Although the catalytic activity of antibody B13‐DE1 is quite low, our results show that monoclonal antibodies can have more than one specificity or function. Three‐dimensional protein structure analyses of the multifunctional antibody B13‐DE1 as well as mutagenesis experiments are needed to determine how this antibody is able to bind fluorescein (Micheel et al , ); to bind structurally related substances as 5‐ and 6‐CF, 5‐ and 6‐aminofluorescein, and phenol red (Bottger et al , ); to bind structurally not related substances as peptides GSWGEW and GPPMVGDWWDW (Bottger et al , ); and to catalyze the redox reaction of resazurin to resorufin using one and the same antigen‐binding region. Such experiments are currently in progress.…”

“…Thus, catalytically active antibodies combine the activity of enzymes with the almost inexhaustible structural diversity provided by the antibody molecule (Schultz and Lerner, ). The murine monoclonal antibody B13‐DE1 has been reported to bind fluorescein (Micheel et al , ), as well as several fluorescein derivatives, phenol red, and some peptides (Bottger et al , ). In this study, we investigated whether the antibody B13‐DE1 was also able to catalyze the redox reaction from resazurin to resorufin using sodium sulfite, as shown previously for other fluorescein binding antibodies (Janjic and Tramontano, ).…”

Characterization of a new maleimido functionalization of gold for surface plasmon resonance spectroscopy

“…(). A mimotope peptide recognized by the anti‐FITC antibody and a human mucin 1 epitope peptide were used as model systems (Böttger et al ., ; Schenk et al ., ; Zvirbliene et al ., ). The peptides were synthesized with N‐terminal cysteine for the covalent coupling to the maleimido‐group (Figure ).…”