Paul Barnas and Meredith Buono

Abstract:

Fluorine is an NMR-active nuclei that enables the investigation of structure and conformational changes of proteins. It can be introduced to proteins using bacterial expression techniques with modified aromatic amino acids, providing a sensitive NMR label in the protein. We aimed to apply this technique to the neurotransmitter synaptotagmin I, which has been implicated as a target of lead poisoning. This protein of interest is proposed to undergo a conformational change when bound to lead rather than its natural metal, calcium, leading to a perturbation of its normal signaling function. Unfortunately, we found that expression of synaptotagmin I in rich and minimal media was poor, likely due to the presence of an unstructured region in the protein construct.