John E. Casida
    Professor and Entomologist
    114 Wellman Hall
    Phone #: (510) 642-5424
    FAX #: (510) 642-7428
    ectl@nature.berkeley.edu




    Research Interests

    Pesticide chemistry and toxicology; metabolism and mode of action of organic toxicants; insect biochemistry



    Current Projects

    Research in the Environmental Chemistry and Toxicology Laboratory emphasizes pesticide mode of action and metabolism. This information is important to optimize pesticide use, improve their selectivity and environmental characteristics, and minimize the hazards of exposure for humans, domestic animals and other nontarget species. The research involves six closely related and interdepen dent topics. The first concerns neuroactive botanical insecticides and their synthetic analogs and involves isolation, identification and synthesis of active compounds and mode of action research. The second utilizes non-neuroactive botanical insecticides as toxicological probes to evaluate the structure-activity factors and metabolic chemistry conferring selectivity to respiratory inhibitors and growth regulators. Another topic examines the toxicology of GABAA receptor antagonists including the conformation and binding characteristics of the GABA-gated chloride channel of insects and mammals relative to the metabolic and target site selectivity of heterocyclic insecticides. The fourth topic characterizes the bioactivation mechanisms and target diversity of phosphorus-containing pesticides with emphasis on non-cholinergic effects, studying not only insecticides but also fumigants and plant growth regulators. Another area examines herbicide mechanisms of mammalian toxicity probing their mode of action relative to their selectivity with emphasis on compounds purported to be carcinogens. Finally, the research attempts to identify reactive intermediates in toxicant action to provide fundamental understanding of adverse toxicological effects from short-lived species implied in bioactivation reactions or environmental alteration processes.




    Selected Publications

    Casida, J.E. and Quistad, G.B. 1995. Pyrethrum Flowers: Production, Chemistry, Toxicology, and Uses. Oxford Univ. Press, New York, 356 pp.

    Cole, L.M., Roush, R.T., and Casida, J.E. 1995. Drosophila GABA-gated chloride channel: modified [3H]EBOB binding site associated with Ala Æ Ser or Gly mutants of Rdl subunit. Life Sci. 56:757-765.

    Yoshida, M., Tomizawa, M., Wu, S.-Y., Quistad, G.B., and Casida, J.E. 1995. Neuropathy target esterase of hen brain: active site reactions with [3H-octyl]- and [3H-aryl]-2-octyl-4H-1,3,2-benzodioxaphosphorin 2-oxides. J. Neurochem. 64:1680-1687.

    Cohen, E., Quistad, G.B., and Casida, J.E. 1996. Cytotoxicity of nimbolide, epoxyazadiradione and other limonids from neem insecticide. Life Sci. 58:1075-1081.

    Wood, E., Latli, B., and Casida, J.E. 1996. Fenazaquin acaricide specific binding sites in NADH: ubiquinone oxidoreductase and apparently the ATP synthase stalk. Pestic. Biochem. Physiol. 54:135-145.


    Current Graduate students:

    • Norman Birchfield
    • Shirley Lee Chao
    • Rick Staub


    Current Post-docs/Researchers/Specialists/SRAs, etc.:

    • Loretta M. Cole, Staff Research Associate
    • Nianbai Fang, Specialist
    • Dominik Hainzl, Postgraduate Researcher
    • Anna Hill, Specialist
    • Gene Hsu, Postgraduate Researcher
    • Jian Huang, Specialist
    • Phillip Jeffries, Specialist
    • Charles Laidley, Postgraduate Researcher
    • Bachir Latli, Specialist
    • Weiwei Li, Specialist
    • Mahmoud Mahajna, Postgraduate Researcher
    • Gary Quistad, Research Toxicologist
    • Craig Rowlands, Postgraduate Researcher
    • Manfred Schneider, Postgraduate Researcher
    • Susan Sparks, Staff Research Associate
    • Motohiro Tomizawa, Specialist