Identification of a new excited state responsible for the in vivo unique absorption band of siphonaxanthin in the green alga Codium fragile.
A marine green alga, Codium fragile, exhibits a characteristic in vivo absorption band of a specific keto-carotenoid, siphonaxanthin, at 535 nm. We examined the ultrafast fluorescence kinetics by direct excitation of this band after purification of light-harvesting complex II. On the basis of a high fluorescence anisotropy (0.39) up to 1 ps and a very short lifetime (60 fs), we identified the 535 nm band as a new electronically excited state (Sx) located between the S1 and S2 states. Excited-state dynamics of the Sx state were further discussed in relation to the energy transfer processes in the complexes.
Akimoto
Seiji
S
Molecular Photoscience Research Center, Kobe University, Kobe 657-8501, Japan. akimoto@hawk.kobe-u.ac.jp
Tomo
Tatsuya
T
Naitoh
Yukito
Y
Otomo
Akira
A
Murakami
Akio
A
Mimuro
Mamoru
M
D000042:Absorption; D000460:Chlorophyta / Q000737:chemistry*; D015394:Molecular Structure; D013053:Spectrophotometry; D013997:Time Factors; D024341:Xanthophylls / Q000737:chemistry*
D024341:Xanthophylls; C003314:siphonaxanthin