Multitarget selection of catalytic antibodies with β‐lactamase activity using phage display. (6th February 2017)

• Record Type: Journal Article
• Authors: Shahsavarian, Melody A.; Chaaya, Nancy; Costa, Narciso; Boquet, Didier; Atkinson, Alexandre; Offmann, Bernard; Kaveri, Srini V.; Lacroix‐Desmazes, Sébastien; Friboulet, Alain; Avalle, Bérangère; Padiolleau‐Lefèvre, Séverine
• Is Part Of: FEBS journal. Volume 284:Number 4(2017)
• Page Start: 634
• Page End: 653
• Publication Date: 2017-02-06
• Subjects: β‐lactamase -- catalytic antibody -- enzyme inhibitor -- phage display -- scFv library; Biochemistry -- Periodicals; Molecular biology -- Periodicals; Pathology, Molecular -- Periodicals; 572
• DOI: 10.1111/febs.14012
• Languages: English
• ISSNs: 1742-464X

Abstract

Abstract : β‐lactamase enzymes responsible for bacterial resistance to antibiotics are among the most important health threats to the human population today. Understanding the increasingly vast structural motifs responsible for the catalytic mechanism of β‐lactamases will help improve the future design of new generation antibiotics and mechanism‐based inhibitors of these enzymes. Here we report the construction of a large murine single chain fragment variable (scFv) phage display library of size 2.7 × 10 9 with extended diversity by combining different mouse models. We have used two molecularly different inhibitors of the R‐TEM β‐lactamase as targets for selection of catalytic antibodies with β‐lactamase activity. This novel methodology has led to the isolation of five antibody fragments, which are all capable of hydrolyzing the β‐lactam ring. Structural modeling of the selected scFv has revealed the presence of different motifs in each of the antibody fragments potentially responsible for their catalytic activity. Our results confirm (a) the validity of using our two target inhibitors for the in vitro selection of catalytic antibodies endowed with β‐lactamase activity, and (b) the plasticity of the β‐lactamase active site responsible for the wide resistance of these enzymes to clinically available inhibitors and antibiotics. Abstract : Three‐dimensional structural modeling of one of the antibody fragments (single chain fragment variable) selected by the phage display technology, against a β‐lactamase inhibitor. Side chains of five putative active sites are displayed, all comprising an active serine and other residues essential to the β‐lactamase activity.