Abstract

Femtosecond laser pulses at 270nm, the Ti:sapphire 3rd harmonic, are utilized to break the S-S bond in small helix bundles that are constrained to be non-helical as a result of the disulfide bridge. The resulting processes involve helix formation and geminate recombination of the sulfhydryl radicals. Both are interesting since they are controlled by the fluctuations of the protein atoms. This project involves quite the new technology of ultraviolet pumping and infrared probing of protein dynamics. A major technical goal of this work is to control the excitation processes that occur when water (or D2O) are irradiated with intense UV pulses. The two photon absorption leads to the efficient formation of solvated electrons which interfere with the methods of probing structure changes in the visible and near IR. Experiments are now underway to probe formation of helix in both water and ?-helix promoting solvents, such as trifluoroethanol (TFE).

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR001348-17
Application #
6281045
Study Section
Project Start
1998-08-01
Project End
1999-07-31
Budget Start
1997-10-01
Budget End
1998-09-30
Support Year
17
Fiscal Year
1998
Total Cost
Indirect Cost

  Institution

Name
University of Pennsylvania
Department
Type
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104

  Publications

Sheth, Rahul A; Arellano, Ronald S; Uppot, Raul N et al. (2015) Prospective trial with optical molecular imaging for percutaneous interventions in focal hepatic lesions. Radiology 274:917-26
Roussakis, Emmanuel; Spencer, Joel A; Lin, Charles P et al. (2014) Two-photon antenna-core oxygen probe with enhanced performance. Anal Chem 86:5937-45
Courter, Joel R; Abdo, Mohannad; Brown, Stephen P et al. (2014) The design and synthesis of alanine-rich ?-helical peptides constrained by an S,S-tetrazine photochemical trigger: a fragment union approach. J Org Chem 79:759-68
Kuroda, Daniel G; Bauman, Joseph D; Challa, J Reddy et al. (2013) Snapshot of the equilibrium dynamics of a drug bound to HIV-1 reverse transcriptase. Nat Chem 5:174-81
Lam, A R; Moran, S D; Preketes, N K et al. (2013) Study of the ?D-crystallin protein using two-dimensional infrared (2DIR) spectroscopy: experiment and simulation. J Phys Chem B 117:15436-43
Kuroda, Daniel G; Singh, Prabhat K; Hochstrasser, Robin M (2013) Differential hydration of tricyanomethanide observed by time resolved vibrational spectroscopy. J Phys Chem B 117:4354-64
Singh, Prabhat K; Kuroda, Daniel G; Hochstrasser, Robin M (2013) An ion's perspective on the molecular motions of nanoconfined water: a two-dimensional infrared spectroscopy study. J Phys Chem B 117:9775-84
Chuntonov, Lev; Ma, Jianqiang (2013) Quantum process tomography quantifies coherence transfer dynamics in vibrational exciton. J Phys Chem B 117:13631-8
Culik, Robert M; Annavarapu, Srinivas; Nanda, Vikas et al. (2013) Using D-Amino Acids to Delineate the Mechanism of Protein Folding: Application to Trp-cage. Chem Phys 422:
Goldberg, Jacob M; Speight, Lee C; Fegley, Mark W et al. (2012) Minimalist probes for studying protein dynamics: thioamide quenching of selectively excitable fluorescent amino acids. J Am Chem Soc 134:6088-91

Showing the most recent 10 out of 128 publications