Publication Date:
1994-10-21
Description:
Femtosecond pump-probe experiments reveal the impulsive production of photoproduct in the primary event in vision. The retinal chromophore of rhodopsin was excited with a 35-femtosecond pulse at 500 nanometers, and transient changes in absorption were measured with 10-femtosecond probe pulses. At probe wavelengths within the photo-product absorption band, oscillatory features with a period of 550 femtoseconds (60 wavenumbers) were observed whose phase and amplitude demonstrate that they are the result of nonstationary vibrational motion in the ground state of the photoproduct. The observation of coherent vibrational motion of the photoproduct supports the idea that the primary step in vision is a vibrationally coherent process and that the high quantum yield of the cis--〉trans isomerization in rhodopsin is a consequence of the extreme speed of the excited-state torsional motion.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Wang, Q -- Schoenlein, R W -- Peteanu, L A -- Mathies, R A -- Shank, C V -- EY-02051/EY/NEI NIH HHS/ -- New York, N.Y. -- Science. 1994 Oct 21;266(5184):422-4.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Materials Sciences Division, Lawrence Berkeley Laboratory, University of California, 94720.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/7939680" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Cattle
;
Fourier Analysis
;
Isomerism
;
*Light
;
Models, Molecular
;
Photic Stimulation
;
Photochemistry
;
Rhodopsin/analogs & derivatives/*chemistry
;
Spectrum Analysis
;
Vision, Ocular/*physiology
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
