Time-Resolved Step-Scan FT-IR Spectroscopy of the Photodynamics of Carbonmonoxymyoglobin

Journal Article

The kinetics of protein response and of CO recombination after photolysis of the Fe-CO bond in carbonmonoxymyoglobin have been monitored via time-resolved step-scan FT-IR absorption difference spectroscopy in D2O solution. Although the initial photodissociation is too fast to observe with currently available FT-IR instrumentation, we have been able to correlate the CO recombination kinetics with protein secondary structural changes via changes in the amide I band of the polypeptide chain with microsecond time resolution. The spectral and kinetic data corroborate and confirm previously published single-frequency infrared studies. This is the first application of time-resolved step-scan FT-IR spectroscopy in the absorbance difference mode to study the photodynamics of an aqueous protein solution at room temperature. This work also demonstrates the potential of the technique for the sub-microsecond kinetic analysis of other biological molecules of interest.

Full Text

Duke Authors

Cited Authors

  • Plunkett, SE; Chao, JL; Tague, TJ; Palmer, RA

Published Date

  • June 1995

Published In

Volume / Issue

  • 49 / 6

Start / End Page

  • 702 - 708

Published By

Electronic International Standard Serial Number (EISSN)

  • 1943-3530

International Standard Serial Number (ISSN)

  • 0003-7028

Digital Object Identifier (DOI)

  • 10.1366/0003702953964633


  • en