Evidence for a very early intermediate in bacterial photosynthesis. A photon-echo and hole-burning study of the primary donor band in Rhodopseudomonas sphaeroides
✍ Scribed by S.R. Meech; A.J. Hoff; D.A. Wiersma
- Publisher
- Elsevier Science
- Year
- 1985
- Tongue
- English
- Weight
- 473 KB
- Volume
- 121
- Category
- Article
- ISSN
- 0009-2614
No coin nor oath required. For personal study only.
✦ Synopsis
Two coheren1 SpecrroKopic melhods, accumulawd pholon echo and population bollleneck hole-burning. have been employed in a sludy or the decay rate or the primary donor (P) of Rhodopseudomona xphoeroides at 1.5 K. The dcczxy rate is insu-umenclimiwd in the photon-echo experiment_ implying a population relaxation rime <lo0 [s. The hole-burning smdy revealed the P absorplion at 900 nm to be largely homogeneour/y broadened. rrom which a decay time of = 25 fs was inrerred. Comparison of these data wilh a photon-echo study 01 Ihe bacreriochlorophyll a monomer suggests char [his ul~rafas~ process is no1 due to vibrational relaxation within P'. bul LO an excited stale eleclronic decay mechanism. II is suggested that rhe inirial even[ aflcr excitation in P is a very rapid charge separation within the dimer pair. prior lo Ihe electron-rransrcr process, which occurs on a much longer rimesck.