Visible fluorescence spectroscopy of single proteins at liquid-helium temperature.
Fluorescence spectroscopy of single proteins at liquid-helium temperatures reveals a relation between structural dynamics and biological functions of the proteins. The technical difficulties in detecting visible fluorescence are chromatic aberration and optical background. They were overcome by a new optical design using reflective optics and employing two-photon excitation. The fluorescence spectrum of single green-fluorescent proteins taken at a temperature of 1.5 K makes a distinction between different metastable conformations that last for tens of seconds.
Fujiyoshi
Satoru
S
Department of Physics, Tokyo Institute of Technology and CREST/JST, Tokyo, 152-8551, Japan. fujiyoshi@phys.titech.ac.jp
Fujiwara
Masanori
M
Matsushita
Michio
M
D003080:Cold Temperature; D049452:Green Fluorescent Proteins / Q000737:chemistry*; D006371:Helium / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000295:instrumentation / Q000379:methods*
D049452:Green Fluorescent Proteins; D006371:Helium