Open AccessPseudomonas exotoxin A: toxoid preparation by photoaffinity inactivation.
Author(s) -
Stephen Marburg,
Richard L. Tolman,
L T Callahan
Publication year - 1983
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.80.10.2870
Subject(s) - photoaffinity labeling , pseudomonas exotoxin , toxoid , exotoxin , toxin , chemistry , biochemistry , nitrene , enzyme , pseudomonas aeruginosa , nad+ kinase , stereochemistry , binding site , biology , bacteria , recombinant dna , antigen , genetics , immunization , gene , catalysis
A method for toxoid preparation has been developed in which toxins expressing enzymatic activity can be detoxified by photoaffinity labeling techniques. In the case of Pseudomonas aeruginosa exotoxin A, the method relies on the affinity of azido-substituted analogs of the substrate (NAD) for the proenzyme form of the toxin. Photolysis of the putative toxin-analog complex results in irreversible inactivation of the toxin without loss of antigenic character. It is proposed that this occurs by nitrene insertion into a chemical bond on the toxin molecule. This affinity photoinactivation process should be applicable to other ADP-ribosylating toxins.