Femtosecond dynamics of proteoheparan sulfate (HS-PG) after UV excitation--a readout for arteriosclerotic nanoplaque formation?
Journal - Biochemical and biophysical research communications (United States )
Ultrashort UV laser pulses were used to excite tryptophan residues of heparan sulfate proteoglycan (HS-PG) in blood substitute Krebs solution. Tryptophan fluorescence is sensitive to the environment, so its shift and decay indicate the conformation and solvation state of the protein. We monitored stimulated emission and excited-state absorption by probing with delayed white-light femtosecond pulses. Comparison with bare tryptophan revealed transient absorption features which are characteristic for HS-PG. Furthermore, the effect of adding calcium salt was investigated. Differences in the spectra from solutions with and without calcium developed during several minutes, which points to changes in protein conformation, but could only be measured in the sub-ps regime. These results provide a first step to a better understanding of the molecular formation of nanoplaques in blood vessels. The goal of this work is to open a way towards biosensing of the initial stages in atherogenesis allowing for a risk assessment in cardiovascular disease.
|ISSN : ||0006-291X|
|Mesh Heading : ||Amino Acid Sequence Arteriosclerosis Base Sequence Biosensing Techniques Calcium Heparan Sulfate Proteoglycans Lasers Molecular Sequence Data Protein Conformation Receptors, LDL Spectrometry, Fluorescence Time Factors Tryptophan pathology pharmacology chemistry drug effects blood|
|Mesh Heading Relevant : ||Ultraviolet Rays blood methods blood chemistry|