INSECT CHITIN SYNTHETASE AS A BIOCHEMICAL PROBE FOR INSECTICIDAL COMPOUNDS

摘要: Abstract Cell-free chitin synthetase (CS) systems derived from insects are available for biochemical and electron microscopy studies. Tribolium castaneum gut enzyme is probably associated with peritrophic membrane formation. Integumental CS active as prepared Trichoplusia ni larvae wing tissues of developing Hyalophora cecropia pharate adults. Electron investigations reveal that polymers formed by chitosome-like structures. The in vitro assembly, spatial organization longitudinal orientation microfibrils suggest these processes independent epidermal cell surfaces might occur outside the site polymerization. under delicate control since physiological state insect drastically affects its activity. Synthesis induced or activity stimulated 20-hydroxyecdysone indicating possible hormonal control. fungal somewhat similar to each other their properties, requirements, sensitivity inhibitory effects nucleotides, pyrimidine nucleoside-peptides, sulfenimides, phenyl carbamates benzoylphenyl ureas. enzymes extracted T. castaneum, H. completely unaffected vivo synthesis inhibitors such ureas, diflubenzuron BAY SIR 8514. Furthermore, studies show polyoxin-D blocked fibrillogenesis insensitive diflubenzuron. This review evaluates five modes action ureas inhibiting synthesis: via a potent metabolite; disruption accessibility substrate activators; interference mechanisms involving removal UDP; inhibition proteolytic required activation presumed zymogenic CS; sensitive mechanism