A catalytic antibody isomerizing a delta 5-3-cétostéroïde.
Antibodies were raised against 3-fluoro-4-aza-estradiol-17-hemisuccinate to elicit abzymes capable of isomerizing delta 5-3-ketosteroids. The hapten was designed to present a planar A ring showing some analogy with the intermediate dienol and a polarity capable of inducing catalytic groups. Antibodies binding the hapten tightly were cloned and purified from either ascites or hybridoma supernatants. Catalytic activity was tested with androst-5-ene-3,17-dione. Among the five different monoclonal antibodies binding the hapten, one proved to enhance significantly the substrate isomerization rate (kcat/kuncat = 830). Initial rates followed Michaelis kinetics and the activity was competitively inhibited by the hapten.
Khettal
B
B
URA 400, CNRS, UFR Biomédicale des Saints-Pères, Paris, France.
de Lauzon
S
S
Desfosses
B
B
Ushida
S
S
Marquet
A
A
D017151:Antibodies, Catalytic / Q000737:chemistry / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000493:pharmacokinetics; D001667:Binding, Competitive; D066298:In Vitro Techniques; D007536:Isomerism; D007664:Ketosteroids / Q000737:chemistry*
D017151:Antibodies, Catalytic; D000911:Antibodies, Monoclonal; D007664:Ketosteroids