Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.
Science Signaling

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Published Online May 23, 2002
Science DOI: 10.1126/science.1071563

Reports

Submitted on March 6, 2002
Accepted on May 15, 2002

Conformational Dynamics in a Dipeptide After Single-Mode Vibrational Excitation

Brian C. Dian 1, Asier Longarte 1, Timothy S. Zwier 1*

1 Department of Chemistry, Purdue University, West Lafayette, IN 47907-1393, USA.

* To whom correspondence should be addressed. E-mail: zwier{at}purdue.edu.

The dynamics of conformational isomerization are explored in a methyl-capped dipeptide, N-acetyl-tryptophan methyl amide (NATMA), using infrared-ultraviolet (IR-UV) hole-filling and IR-induced population transfer spectroscopies. IR radiation selectively excites individual NH stretch vibrational fundamentals of single conformations of the molecule in the early portions of a gas-phase expansion, and then this excited population is collisionally re-cooled into its conformational minima for subsequent conformation-specific detection. Efficient isomerization is induced by the IR excitation that redistributes population between the same conformations that have population in the absence of IR excitation. The quantum yields for transfer of the population into the various conformational minima depend uniquely on which conformation is excited and on which NH stretch vibration is excited within a given conformation.



THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Measuring Picosecond Isomerization Kinetics via Broadband Microwave Spectroscopy.
B. C. Dian, G. G. Brown, K. O. Douglass, and B. H. Pate (2008)
Science 320, 924-928
   Abstract »    Full Text »    PDF »
Conformationally Controlled Chemistry: Excited-State Dynamics Dictate Ground-State Reaction.
M. H. Kim, L. Shen, H. Tao, T. J. Martinez, and A. G. Suits (2007)
Science 315, 1561-1565
   Abstract »    Full Text »    PDF »
Chemical Theory and Computation Special Feature: Vibrational energy relaxation in proteins.
H. Fujisaki and J. E. Straub (2005)
PNAS 102, 6726-6731
   Abstract »    Full Text »    PDF »
Laser-Initiated Shuttling of a Water Molecule Between H-Bonding Sites.
J. R. Clarkson, E. Baquero, V. A. Shubert, E. M. Myshakin, K. D. Jordan, and T. S. Zwier (2005)
Science 307, 1443-1446
   Abstract »    Full Text »    PDF »
MoViES: molecular vibrations evaluation server for analysis of fluctuational dynamics of proteins and nucleic acids.
Z. W. Cao, Y. Xue, L. Y. Han, B. Xie, H. Zhou, C. J. Zheng, H. H. Lin, and Y. Z. Chen (2004)
Nucleic Acids Res. 32, W679-W685
   Abstract »    Full Text »    PDF »
Vibrational Transition Moment Angles in Isolated Biomolecules: A Structural Tool.
F. Dong and R. E. Miller (2002)
Science 298, 1227-1230
   Abstract »    Full Text »    PDF »



ADVERTISEMENT
Click Me!

ADVERTISEMENT
Click Me!

To Advertise     Find Products


Science. ISSN 0036-8075 (print), 1095-9203 (online)