Enzymes antibody formation

Antibody-enzyme conjugate formation through thioether bond... 

Both enzymes and antibodies are proteins. Antibodies consist of subunits with multiple domains, just as do some enzymes. Both enzymes and antibodies have binding sites for small molecules between domains or subunits. In view of such similarities it isn t surprising that some antibodies have catalytic properties. The possibility was suggested in 1969 by Jencks 3 He also proposed that injection of a mouse with a hapten, that resembled a transition state for an enzyme, might induce formation of antibodies complementary to the transition-state structure. These might be catalytic. By the early 1980s such antibodies were discovered.1 d Some of the first catalytic antibodies (also dubbed abzymes) had esterase activity. The haptens used to induce antibody formation were phosphonates such as the following.e f... 

Catalytic antibodies, like enzymes, must be isolated and purified to homogeneity before they can be studied. Initially this was done by using the hybridoma technique for isolation of monoclonal antibodies (Box 31-A). After induction of antibody formation by injecting a selected hapten into a mouse, large numbers of monoclonal antibodies had to be tested for catalytic activity. Even if several thousand different monoclonal antibodies were tested, only a few with catalytic properties could be found.1 Newer methods have incorporated recombinant DNA techniques (Box 31-A) and use of combinatorial libraries and phage display.) Incorporation of acidic or basic groups into the haptens used to induce antibody formation may yield antibodies capable of mimicking the acid-base catalysis employed by natural enzymes. 0... 

Antibody-Enzyme Conjugate Formation through Thioether Bond... 

Zhao, L., J.-M. Lin, Z. Li, et al. 2006. Development of a highly sensitive, second antibody format chemiluminescence enzyme immunoassay for the determination of 17[beta]-estradiol in wastewater. Anal. Chim. Acta 558 290-295. 

B27, the HLA allele proposed to be involved in alkylosing spondylitis, shares an epitope with an enzyme from Klebsiella pneumoniae, a common intestinal Gram negative bacterium. Molecular mimicry is thought to result in cross-reactive antibody formation, joint inflammation and spinal damage. Along with many of the immunotherapies described for other similar arthritic autoimmune disorders, alkylosing spondylitis is treated with anti-inflammatory medications and a low carbohydrate diet to reduce intestinal K. pneumoniae levels. 

Enzyme-antibody complex formation represents the simplest among the immunoaffinity immobilization procedures and the immunocomplexes can be readily formed simply by mixing of the enzyme solution with the antibody or even antiserum. Interestingly neither pure enzyme nor pure antibody may be required for the formation of immunocomplexes. Several early [14,36,39] and some recent studies [22,24,28] indicate high retention of catalytic activities by various enzymes in the immunocomplexes and marked stability enhancement against various forms of inactivation. The small particle dimensions of the enzyme-antibody complexes may however lead to their compact packing and consequently to slow flow-rates in the column reactors. Their usefulness can be however remarkably enhanced by entrapping the complexes in a polymeric matrix [60,61]. 

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