Dataset Information

Epitope mapping of a 95 kDa antigen in complex with antibody by solution-phase amide backbone hydrogen/deuterium exchange monitored by Fourier transform ion cyclotron resonance mass spectrometry.

ABSTRACT: The epitopes of a homohexameric food allergen protein, cashew Ana o 2, identified by two monoclonal antibodies, 2B5 and 1F5, were mapped by solution-phase amide backbone H/D exchange (HDX) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) and the results were compared to previous mapping by immunological and mutational analyses. Antibody 2B5 defines a conformational epitope, and 1F5 defines a linear epitope. Intact murine IgG antibodies were incubated with recombinant Ana o 2 (rAna o 2) to form antigen-monoclonal antibody (Ag-mAb) complexes. mAb-complexed and uncomplexed (free) rAna o 2 were then subjected to HDX. HDX instrumentation and automation were optimized to achieve high sequence coverage by protease XIII digestion. The regions protected from H/D exchange upon antibody binding overlap and thus confirm the previously identified epitope-bearing segments: the first extension of HDX monitored by mass spectrometry to a full-length antigen-antibody complex in solution.

SUBMITTER: Zhang Q

PROVIDER: S-EPMC3173601 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Epitope mapping of a 95 kDa antigen in complex with antibody by solution-phase amide backbone hydrogen/deuterium exchange monitored by Fourier transform ion cyclotron resonance mass spectrometry.

Zhang Qian Q Willison LeAnna N LN Tripathi Pallavi P Sathe Shridhar K SK Roux Kenneth H KH Emmett Mark R MR Blakney Greg T GT Zhang Hui-Min HM Marshall Alan G AG

Analytical chemistry 20110823 18

The epitopes of a homohexameric food allergen protein, cashew Ana o 2, identified by two monoclonal antibodies, 2B5 and 1F5, were mapped by solution-phase amide backbone H/D exchange (HDX) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) and the results were compared to previous mapping by immunological and mutational analyses. Antibody 2B5 defines a conformational epitope, and 1F5 defines a linear epitope. Intact murine IgG antibodies were incubated with recom ...[more]

PMID: 21861454

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Dataset Information

Epitope mapping of a 95 kDa antigen in complex with antibody by solution-phase amide backbone hydrogen/deuterium exchange monitored by Fourier transform ion cyclotron resonance mass spectrometry.

Publications

Epitope mapping of a 95 kDa antigen in complex with antibody by solution-phase amide backbone hydrogen/deuterium exchange monitored by Fourier transform ion cyclotron resonance mass spectrometry.

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