Dr. Li investigates the protein involved in the metabolism of aromatic amino acids.
Aromatic amino acids, like other proteinogenic amino acids, are building blocks of proteins. Moreover, they serve as precursors for the synthesis of many neurologically active compounds that are essential for maintaining the normal brain functions in human and other species. For example, tryptophan is the initial precursor for the biosynthesis of tryptamine, serotonin, and melatonin. Kynurenic acid, produced along the tryptophan-kynurenine pathway, is an antagonist at excitatory amino acid receptors and plays a role in protecting neurons from overstimulation by excitatory neurotransmitters. Tyrosine is the initial precursor for the biosynthesis dopa, dopamine, norepinephrine and epinephrine. In addition, tyrosine is the precursor for melanin synthesis.
Our current research includes the determination of the structure-function relationship of proteins involved in kynurenic acid biosynthesis along the tryptophan-kynurenine pathway in the mouse model. Our current studies also include characterization of proteins involved in tyrosine metabolisms in insects and mammals. We have active research collaboration with colleagues at VT in Chemistry and Entomology, at the University of Wisconsin-Madison and at NIH.