Sci. Signal., 11 September 2012
Biochemistry Responding to Light and Heat
Science, AAAS, Washington, DC 20005, USA
The protein rhodopsin is sensitive to dim light, but its sensitivity is limited by signals caused by the noise of thermal activation. The basis of this relationship, known as the Barlow correlation, has long been debated. A recent study suggested that thermal activation involves a canonical isomerization reaction. Gozem et al. confirm that isomerization is the rate-limiting step controlling thermal noise, and they provide a molecular understanding of the Barlow correlation. They use quantum mechanics coupled with molecular mechanics to show that the transition state mediating thermal activation has the same electronic structure as the photochemical excited state.
Citation: V. Vinson, Responding to Light and Heat. Sci. Signal. 5, ec242 (2012).
The editors suggest the following Related Resources on Science sites:
In Science Signaling
Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882