Two-dimensional infrared correlation analysis of protein unfolding : use of spectral simulations to validate structural changes during thermal denaturation of bacterial CMP kinases

Download
  1. Get@NRC: Two-dimensional infrared correlation analysis of protein unfolding : use of spectral simulations to validate structural changes during thermal denaturation of bacterial CMP kinases (Opens in a new window)
DOIResolve DOI: http://doi.org/10.1366/0003702001950562
AuthorSearch for: ; Search for: ; Search for:
TypeArticle
Journal titleApplied Spectroscopy
ISSN0003-7028
1943-3530
Volume54
Issue7
Pages931938; # of pages: 8
SubjectTwo-dimensional IR correlation spectroscopy; 2D-IR; FT-IR spectroscopy; Protein folding; Protein secondary structure analysis
AbstractThe functional role of bacterial CMP kinases is to recover the energetically exhausted nucleoside monophosphates derived from cell metabolism by transferring a phosphate residue from ATP to CMP or dCMP. These enzymes—important for cell growth and division—possess two distinct binding sites and a number of conserved secondary structure elements. Herein we compare the infrared spectra of two similar, but not identical, CMP kinases from Escherichia coli and Bacillus subtilis. The two-dimensional correlation analysis of the infrared spectra of the two enzymes reveals significant differences in protein structure upon denaturation, a fact possibly linked to their different biochemical and catalytic properties. Model calculations are used to illustrate the effect of two separate processes on the out-of-phase correlation in the two-dimensional (2D) correlation plots. This strategy is then employed to validate the changes observed in the secondary structure of the two enzymes. When bound to the active site of the protein, the two substrates CMP and ATP exert a stabilizing effect on the structure of both proteins; however, the changes observed upon thermal denaturation are different for the two enzymes. Model 2D correlations that simulate the denaturation of the two enzymes confirm the occurrence of temperature-delayed unfolding processes in both proteins. Thermal denaturation and aggregation can be distinguished in both proteins as two distinct processes, separated in time.
Publication date
PublisherSociety for Applied Spectroscopy
AffiliationNRC Institute for Biodiagnostics; National Research Council Canada
Peer reviewedYes
NRC number1824
NPARC number9148472
Export citationExport as RIS
Report a correctionReport a correction
Record identifier3b74163e-6dfe-4665-8424-0adbae1e5992
Record created2009-06-25
Record modified2016-10-05
Bookmark and share
  • Share this page with Facebook (Opens in a new window)
  • Share this page with Twitter (Opens in a new window)
  • Share this page with Google+ (Opens in a new window)
  • Share this page with Delicious (Opens in a new window)