Research Interests

Until recently biochemists and biophysicists were not accustomed to think of cell processes in mechanical terms, in part, because they lacked the appropriate methods to directly detect and measure the tiny mechanical forces generated in the course of biochemical reactions. During the last 10 years my efforts have been directed toward the development and application of methods of single-molecule manipulation, such as force microscopes, magnetic tweezers, and force-measuring laser tweezers. These methods make it possible not only to measure these tiny forces but also to apply external forces to change the extent and even the fate of biochemical reactions, and to learn about the molecular mechanisms by which chemical energy is converted into mechanical work in these reactions. In part as a result of these efforts it is now becoming apparent that many cellular processes involve mechanical processes and many utilize molecular machines capable of converting part of the free energy of the reaction (binding energy, chemical gradient and ATP hydrolysis) into mechanical work and into the generation of force. I am now using single-molecule approaches to study the mechanical unfolding of proteins and RNA, to study the operation of nucleic-acid-binding molecular motors such as RNA and DNA polymerases, and to characterize the mechanical properties of proteins and nucleic acids to better understand their performance in the cell.

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Primary Section

Section 29: Biophysics and Computational Biology

Secondary Section

Section 21: Biochemistry