Professor George I. Makhatadze of Rensselaer Polytechnic Institute is supported by the Chemistry of Life Processes Program in the Division of Chemistry to develop and experimentally test models of how biomacromolecules such as proteins and DNA respond and adapt to high hydrostatic pressure. The Molecular Biophysics Cluster in the Division of Molecular and Cellular Biosciences, and the Physics of Living Systems Program in the Division of Physics also contribute to this award. Hydrostatic pressure is an important environmental variable that plays a role in biological adaptation for many extremophilic organisms - organisms that can tolerate and even thrive under extreme environmental conditions. On Earth, pressure-tolerant barophiles generally populate the deep ocean floor, where the pressures on their bodies can reach 110 MPa (~1,100 atm). This project is utilizing a combination of computational modeling and biochemical and biophysical experiments to determine the pressure-dependence of protein and nucleic acid stability in extremophilic organisms. They also examine the role of hydrostatic pressure in modulating protein-DNA interactions. The results of this project may enable prediction of pressure-dependent growth phenotypes of diverse organisms. The project may also help in the design of next-generation, environmentally-friendly catalysts and robust biomaterials. Research topics and recent findings from the lab are integrated into Professor Makhatadze's teaching as part of the Biochemistry and Biophysics major at RPI. The project engages graduate students, and high school students and undergraduates in interdisciplinary research, providing specialized training in a diverse and unique scientific skill set.
The objectives of this project are to probe at the structural proteome level the differences in volumetric properties of thermophilic, psychrophilic and barophilic organisms. The research provides quantitative understanding of the effects of hydrostatic pressure on protein-DNA interactions and nucleic acids. This understanding is being achieved by uniquely combining biochemical and biophysical experiments with computational tools to interrogate and compare volume changes upon protein unfolding in specific barophilic organisms at the structural proteome level. The research team also investigates the effects of hydrostatic pressure on stability of alpha-helices, and compares model predictions against high-pressure cell measurements of volume changes due to helix-coil transitions. Dr. Makhatadze analyzes the effects of hydrostatic pressure, including hydration, on the stability of nucleic acids as the progenitor building blocks of life and investigate the effects of hydrostatic pressure on protein-DNA interactions, for comparison with high-pressure fluorescence experiments. In addition to training graduate researchers in interdisciplinary computational and experimental research at the intersection of biophysics and biochemistry, the team mentors high school and undergraduate students as active, ongoing participants in laboratory research. Outreach to minority undergraduates through summer internships are provided by the Rensselaer's Louis Stokes Alliance for Minority Participation (LSAMP) program.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
