Direct Observation of Energy Transfer in a Photosynthetic Membrane: Chlorophyll b to Chlorophyll a Transfer in LHC

نویسندگان

  • Daniel D. Eads
  • Graham R. Fleming
چکیده

Subpicosecond fluorescence upconversion has been used to measure the rate of chlorophyll b to chlorophyll a electronic energy transfer in situ within the LHC pigment proteins of Chlamydomonas reinhardtii mutant C2. The time scale of energy transfer is 0.5 & 0.2 ps as determined from the rise time of chlorophyll a fluorescence following chlorophyll b excitation. Estimates of the energy-transfer rate based on Forster weak coupling theory are discussed.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Direct observation of multistep energy transfer in LHCII with fifth-order 3D electronic spectroscopy

During photosynthesis, sunlight is efficiently captured by light-harvesting complexes, and the excitation energy is then funneled towards the reaction centre. These photosynthetic excitation energy transfer (EET) pathways are complex and proceed in a multistep fashion. Ultrafast two-dimensional electronic spectroscopy (2DES) is an important tool to study EET processes in photosynthetic complexe...

متن کامل

Characterization of three forms of light-harvesting chlorophyll a/b-protein complexes of photosystem II isolated from the green alga, Dunaliella salina.

Three forms of light-harvesting chlorophyll a/b-protein complexes of photosystem II (LHC II) were isolated from the thylakoid membranes of Dunaliella salina grown under different irradiance conditions. Cells grown under a low intensity light condition (80 micromol quanta m(-2) s(-1)) contained one form of LHC II, LHC-L. Two other forms of LHC II, LHC-H1 and LHC-H2, were separated from the cells...

متن کامل

Formation of chlorophyll B, and the fluorescence properties and photochemical activities of isolated plastids from greening pea seedlings.

Chlorophyll b was first detectable after 10 minutes of illumination of etiolated pea seedlings (Pisum sativum L. var Greenfeast) with continuous white light. The chlorophyll a/b ratio decreased from 300 at 10 minutes to 15 after 1 hour. There was little change in the chlorophyll a/b ratio between 1 and 2 hours, and it declined to 3 between 2 and 5 hours of illumination. In red light, the time c...

متن کامل

تأثیر تنش خشکی بر خصوصیات فتوسنتزی، ترکیبات فنلی و ظرفیت مهار رادیکال‌های فعال ژنوتیپ‌های مختلف نخود (Cicer arietinum L.) در محیط آبکشت

Low photosynthetic rate is a major reason for yield reduction in drought-stress conditions. Therefore, a study was conducted in order to investigate the effect of drought stress on gas exchange, chlorophyll florescence, photosynthetic pigments, membrane stability, phenolic compounds and antioxidant capacity of leaves and their association with drought tolerance in 12 chickpea genotypes, which w...

متن کامل

Photosynthetic Acclimation to Temperature in the Desert Shrub, Larrea divaricata: II. Light-harvesting Efficiency and Electron Transport.

The response of photosynthetic electron transport and light-harvesting efficiency to high temperatures was studied in the desert shrub Larrea divaricata Cav. Plants were grown at day/night temperatures of 20/15, 32/25, or 45/33 C in rough approximation of natural seasonal temperature variations. The process of acclimation to high temperatures involves an enhancement of the stability of the inte...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2001