Reaction with exocyclic and endocyclic nitrogen nucleophiles in purine bases has been shown to be responsible for the genetic damage which ensues upon ingestion of these substances. We will attempt a larger scale natural product isolation commencing with Soxhlet continuous extraction of ground roots. We will then bring various 1D and 2D NMR experiments to bear on structure elucidation. A cell gains information from its environment by binding molecules called ligands. These bind to specific cell surface receptors which then transmit these signals to the interior inducing a change in the activity of the cell.
T cells are an important part of the immune system and aid in fighting disease.
We will use T cell lines which are easy to grow in culture. Aggregating TCR complexes on the cell surface is necessary to activate the cells and causes a number of biochemical changes which can be measured. Experiments over the past few of years have shown that aggregation induces the receptors to associate with certain specialized areas of the plasma membrane. Due to the structure of the glycolipids, these membrane domains are relatively resistant to solubilization by mild detergents that are normally used to dissolve the membrane lipids and release membrane proteins. We have had some success separating, purifying, and analyzing the aggregated TCR complexes and membrane domains using density gradient centrifugation.