Site-specific photocoupling of pBpa mutated scFv antibodies for use in affinity proteomics

Biochim Biophys Acta Proteins Proteom. 2017 Aug;1865(8):985-996. doi: 10.1016/j.bbapap.2017.03.007. Epub 2017 Mar 22.

Abstract

Recombinant antibody libraries can provide a source of renewable and high-performing binders tailored for use in affinity proteomics. In this context, the process of generating site-specific 1:1 tagging/functionalization and/or orientated surface immobilization of antibodies has, however, proved to be challenging. Hence, novel ways of generating such engineered antibodies for use in affinity proteomics could have a major impact on array performance. In this study, we have further tailored the design of human recombinant scFv antibodies for site-specific photocoupling through the use of an unnatural amino acid (UAA) and the Dock'n'Flash technology. In more detail, we have generated the 2nd generation of scFvs carrying the photoreactive UAA p-benzoyl-l-phenylalanine (pBpa). Based on key properties, such as expression levels, activity, and affinity, a preferred choice of site for pBpa, located in the beginning of the C-terminal affinity-tag, was for the first time pin-pointed. Further, the results showed that pBpa mutated antibody could be site-specifically photocoupled to free and surface immobilized β-cyclodextrin (an affinity ligand to pBpa). This paves the way for use of scFv antibodies, engineered for site-specific photochemical-based tagging, functionalization, and orientated surface immobilization, in affinity proteomics.

Keywords: Antibody engineering; Antibody microarray; Dock'n'Flash; Photochemistry; Site-specific coupling; Unnatural amino acids; scFv antibodies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibody Affinity / immunology*
  • Benzophenones / immunology*
  • Benzophenones / metabolism*
  • Humans
  • Mutation / genetics*
  • Mutation / immunology
  • Phenylalanine / analogs & derivatives*
  • Phenylalanine / immunology
  • Phenylalanine / metabolism
  • Protein Engineering / methods
  • Proteomics / methods
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / immunology
  • Recombinant Fusion Proteins / metabolism
  • Single-Chain Antibodies / genetics
  • Single-Chain Antibodies / immunology*
  • Single-Chain Antibodies / metabolism*
  • beta-Cyclodextrins / immunology
  • beta-Cyclodextrins / metabolism

Substances

  • 4-benzoylphenylalanine
  • Benzophenones
  • Recombinant Fusion Proteins
  • Single-Chain Antibodies
  • beta-Cyclodextrins
  • Phenylalanine
  • betadex