[Super catalytic antibodies (antigenase) capable of destroying H. pylori urease]

Uda Taizo1, Emi Hifumi, Yoshiko Okamura

  • 1Faculty of Life and Environmental Science, Prefectural University of Hiroshima.

Antigenase has an ability to decompose the antigen peptide or protein. We have produced some monoclonal antibodies(HpU mAbs series) for H. pylori urease. Out of them, the light chain of HpU-9 mAb possesses a catalytic triad composed of Asp, Ser and His, which acts as a catalytic site against the antigen, based on the structural analysis of molecular modeling. HpU-9-L belongs to the germline cs1 which inherently encodes the catalytic triads in the sequence, indicating that HpU-9-L must be an antigenase. As expected, HpU-9-L showed the specific degradation against the beta-subunit of the urease. The heavy chain of HpU-2 also exhibited the specific degradation of the urease. These antigenases will be used for the medicinal application.

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