Chemical Biological Research of Pesticides
Chemical biological approaches have been intensively implicated in discovering novel chemical pesticides.Biochemical assays provide the most reliable way to screen the potential leads. Understanding of the kinetics, structure and dynamics of thetargeting enzymes is used to establish proofs that whether the predictions from rational design reflect the truth or not. Current and future research on the chemical biology of pesticide within Yang group mainly focuses on the two areas listed below.
Area 1.Activity screening, kinetic analysis and SAR study for agonists or antagonists.
We developed and implemented several screening methods and platforms to evaluate the biological activity of natural products and chemically synthesized small molecules. Our research efforts over the past few years resulted in the establishment of quantitative assay systems measuring a series of biologically indispensable targets, such as cytochrome bc1 complexes (complex III),succinate dehydrogenase (complex II), acetylcholinesterase (AChE), butyrylcholinesterase(BChE), and 4-hydroxyphenylpyruvate dioxygenase (HPPD). The techniques utilized in our bioanalysis include at least three methodologies:
- enzyme based assay to study the potency of compound under standard condition;
- cell based assay to study the stability, cell penetrability and cytotoxicity of compound;
- living organism based assay to study the in vivo activity of compound under real environment.
Area 2.Mechanism study of enzymatic catalysis and the inhibition caused by inhibitors.
This research lies in elucidating the structural basis by which the particular enzyme catalyzes the conversion of its natural substrate, as well as the modulation mechanism by a specific inhibitor, which is believed to enhance the process for pesticide discovery. Our work illuminated or to illuminate the biochemical and structural basis for enzymatic recognition of substrate or inhibitors by using site-directed mutagenesis, crystallographic study, circular dichroism (CD) and kinetic characterization.