Mark Williams

Affiliated Faculty,  Bioengineering
Professor & Chair,  Physics


Social Media


  • 617.373.5705

Research Focus

single molecule biophysics, molecular biophysics

Honors & Awards

  • Editorial Board Member, Biophysical Journal, 2020-present
  • Fellow, American Physical Society, Elected 2012
  • Editorial Board Member, Nucleic Acids Research, 2011-present

Research Overview

single molecule biophysics, molecular biophysics

Williams Laboratory for Single Molecule Biophysics

The Williams lab specializes in the development of single molecule methods for quantitatively probing the biophysical properties of DNA and RNA and for understanding the biophysics of their interactions with proteins and other DNA binding ligands. These methods are used to probe nucleic acid interactions in order to understand the role of these interactions in processes such as replication and transcription. Specifically, the lab studies single-stranded DNA binding proteins from viruses and bacteria, retroviral replication proteins such as HIV-1 nucleocapsid and Gag proteins, bacterial polymerases, small molecules that bind to DNA and may inhibit cellular replication, and nuclear proteins such as HMG proteins. At the heart of all of these studies is the search for the mechanism by which these proteins interact with DNA in order to alter its biophysical properties, thereby achieving their specific biological activity. In order to understand these mechanisms, these studies are done in collaboration with experts in each biological system, and the activities of the proteins are monitored in a variety of in vitro and in vivo studies to determine how the observed biophysical mechanism is manifested on the level of a more complete biological system.

Williams Laboratory for Single Molecule Biophysics

Selected Publications

  • Naufer, M.N., Morse, M., Möller, G.B., McIsaac, J., Rouzina, I., Beuning, P.J., and Williams, M.C. (2021). Multiprotein E. coli SSB-ssDNA complex shows both stable binding and rapid dissociation due to interprotein interactions Nucleic Acids Research 49: 1532-1549.
  • McCauley, M., Rouzina, I., Li, J., Nunez, M., Williams, M.C. (2020). Significant Differences in RNA Structure Destabilization by HIV-1 GagΔp6 and NCp7 Proteins. Viruses 12: 484.
  • Michael Morse, M. Naufer, N., Feng, Y., Chelico, L., Rouzina, I., and Williams, M.C. (2019). HIV Restriction Factor APOBEC3G Binds in Multiple Steps and Conformations to Search and Deaminate Single-Stranded DNA. eLife 8: e52649.
  • Almaqwashi, A.A., Zhou, W., Naufer, M.N., Riddell, I.A., Yilmaz, Ö.H., Lippard, S.J., and Williams, M.C. (2019). DNA Intercalation Facilitates Efficient DNA-Targeted Covalent Binding of Phenanthriplatin. Journal of the American Chemical Society 141: 1537-1545 (2019).
  • McCauley, M.J., Huo, R., Becker, N., Holte, M.N., Muthurajan, U.M., Rouzina, I., Luger, K., Maher III, L.J., Israeloff, N.E, Williams, M.C. (2019). Single and Double Box HMGB Proteins Differentially Destabilize Nucleosomes. Nucleic Acids Research, 47: 666-678.