Irina Nesmelova

Our research area is experimental biophysics. We are trying to understand the molecular logic underlying biological function. By nature, the research is highly interdisciplinary. Students will learn spectroscopic techniques (Nuclear Magnetic Resonance (NMR), circular dichroism (CD), fluorescence), molecular modeling, and gain basic biochemistry skills.

Projects

Structure-function-dynamics of proteins

DNA transposition is the mechanism that can be used to deliver genetic information to mammalian genome. It has been employed for gene therapy and for functional genomics studies. The Sleeping Beauty (SB) transposon system is the most frequently used DNA transposon in functional genomics, and is the first and only DNA transposon that has been adapted for human gene therapy. The SB system consists of the transposase enzyme and of the transposon DNA. From the biophysics point of view, the SB transposition is the sequence of steps during which the transposase interacts with the transposon DNA. Accordingly, we study these steps to create a dynamic picture with atomic-level resolution of how molecular components of the SB transposon system work together.

Protein-protein interactions

Chemokines form a large family of proteins that guide the migration of leukocytes in our body. We need chemokines to fight the infection, but they can also play a negative role by promoting autoimmune and allergic inflammatory reactions, cancer, atherosclerosis, or other inflammatory disorders. Chemokines act individually or interact to form heterooligomers. These interactions alter the biological activity of individual chemokines. We are looking at different chemokines to describe their interactions at atomic level in order to design molecule that will block (or enhance) the interactions, because we believe that it may lead to the development of more targeted, anti-inflammatory pharmacological agents with minimal side effects.

Translational diffusion of proteins

Biological processes depend on diffusive transport of molecules within cell and tissue. The first step of a biochemical reaction is the translational diffusion of at least one species to recognize another species involved in the reaction. To date, the translational diffusion of biopolymers, primarily globular proteins, has been studied in dilute solutions – idealized conditions required in most biophysical studies. We aim to understand the diffusion of biopolymers in solution in a wide range of concentrations when crowding is created by like or dislike molecules.

Plant defensins

Plant defensins form a family of proteins with a broad spectrum of protective activities against fungi, bacteria, and insects. Furthermore, some plant defensins have revealed anticancer activity. In general, plant defensins are non-toxic to plant and mammalian cells, and interest in using them for biotechnological and medicinal purposes is growing. The goal of this project is to gain an insight into structure, dynamics, and the mechanism of action of defensins from Pinus sylvestris.

Funding