B. Montgomery Pettitt, PhD
Director, Sealy Center for Structural Biology and Molecular Biophysics
Robert A. Welch Distinguished Chair in Chemistry, Department of Pharmacology & Toxicology
Professor, Departments of Pharmacology & Toxicology, and Biochemistry & Molecular Biology
Tel: (409) 772-0723
Fax: (409) 772-0725
E-mail: mpettitt@utmb.edu
Campus Location: 5.404A Research Bldg 6
Mail Route: 0304
Lab Web Page
Research
The research in my laboratory involves work in the areas of : (1)
Biochemistry, (2) Chemical Physics/Physical Chemistry and (3) Computer
Science. In particular, I am interested in
- Bacteriophages, found in bacteria-rich locations like rivers and
soil, are nature's machinery for viral infection of bacteria. Their
genetic material, DNA or RNA, single- or double-stranded, are carried in
protein-based capsids and released into the bacteria. Understanding the
biophysical basis of the biological process which transfers a viral
genome to infect a cell is important to the cellular machinery and many
disease related fields. Predicting the thermodynamic pressures including
the osmotic pressure necessary to confine DNA in a specific volume,
like a phage, is a problem with implications in genomics,
nanotechnology, infection, phage therapies and therapeutic delivery.
DNA, a charged elastic polymer, undergoes over 250-fold compaction when
packed into a capsid overcoming an unfavorable thermodynamic barrier by
using ATP. How DNA overcomes the unfavorable thermodynamic barrier to
enter and pack inside a capsid depends on the interplay of many
different intermolecular interactions. Combined with experimental data,
coarse-grained models and multi-scale techniques are being employed to
model the structure and, consequently, the thermodynamics of DNA
confined by surfaces.
- Forces and structures governing thermodynamics and kinetics in
liquid solutions especially aqueous systems. Most difficult is the
question of how multicomponent systems including cosolvents and ions
affect the structure of proteins and nucleic acids in solution. Given
correlations and statistical thermodynamics the relations to
experimental observables on the effects ions and osmolytes have on
biomacromolecules in solution should then be understandable. At the
technical level we are working on activity models and diagramatic
expansion.
- Effects of anisotropic environments on DNA and Proteins:
Tethering biomolecules to surfaces characterizes a wide variety of
biotechnological devices including microarrays, nano beads, next
generation sequencing etc. However the effects of electric fields,
solvent gradients and density waves near surfaces has a profound effect
on conformation and binding. Both theoretical and simulation methods are
being developed to address these problems.
- Theory and computational methods to investigate solution systems
with couplings and correlations at many disparate length and time
scales. There are many problems for which atomic correlations do not
provide a direct link to macroscopic properties. Connecting meso scale
averaging procedures to the atomic and macro levels via multiscale
methods is important for biological/materials applications.
- Computational theory of exotic statistical ensembles and
sampling methods. In particular the use of chemical potential to
calculate phase related behavior requires sampling tricks. Application
to systems at constant activity to explore phase transitions in saline
solution and protein folding in multicomponent systems is of interest.
Publications