+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Energy transfer in light-harvesting complexes LHCII and CP29 of spinach studied with three pulse echo peak shift and transient grating



Energy transfer in light-harvesting complexes LHCII and CP29 of spinach studied with three pulse echo peak shift and transient grating



Biophysical Journal 84(1): 450-465



Three pulse echo peak shift and transient grating (TG) measurements on the plant light-harvesting complexes LHCII and CP29 are reported. The LHCII complex is by far the most abundant light-harvesting complex in higher plants and fulfills several important physiological functions such as light-harvesting and photoprotection. Our study is focused on the light-harvesting function of LHCII and the very similar CP29 complex and reveals hitherto unresolved excitation energy transfer processes. All measurements were performed at room temperature using detergent isolated complexes from spinach leaves. Both complexes were excited in their Chl b band at 650 nm and in the blue shoulder of the Chl a band at 670 nm. Exponential fits to the TG and three pulse echo peak shift decay curves were used to estimate the timescales of the observed energy transfer processes. At 650 nm, the TG decay can be described with time constants of 130 fs and 2.2 ps for CP29, and 300 fs and 2.8 ps for LHCII. At 670 nm, the TG shows decay components of 230 fs and 6 ps for LHCII, and 300 fs and 5 ps for CP29. These time constants correspond to well-known energy transfer processes, from Chl b to Chl a for the 650 nm TG and from blue (670 nm) Chl a to red (680 nm) Chl a for the 670 nm TG. The peak shift decay times are entirely different. At 650 nm we find times of 150 fs and 0.5-1 ps for LHCII, and 360 fs and 3 ps for CP29, which we can associate mainly with Chl b <--> Chl b energy transfer. At 670 nm we find times of 140 fs and 3 ps for LHCII, and 3 ps for CP29, which we can associate with fast (only in LHCII) and slow transfer between relatively blue Chls a or Chl a states. From the occurrence of both fast Chl b <--> Chl b and fast Chl b --> Chl a transfer in CP29, we conclude that at least two mixed binding sites are present in this complex. A detailed comparison of our observed rates with exciton calculations on both CP29 and LHCII provides us with more insight in the location of these mixed sites. Most importantly, for CP29, we find that a Chl b pair must be present in some, but not all, complexes, on sites A(3) and B(3). For LHCII, the observed rates can best be understood if the same pair, A(3) and B(3), is involved in both fast Chl b <--> Chl b and fast Chl a <--> Chl a transfer. Hence, it is likely that mixed sites also occur in the native LHCII complex. Such flexibility in chlorophyll binding would agree with the general flexibility in aggregation form and xanthophyll binding of the LHCII complex and could be of use for optimizing the role of LHCII under specific circumstances, for example under high-light conditions. Our study is the first to provide spectroscopic evidence for mixed binding sites, as well as the first to show their existence in native complexes.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 010588037

Download citation: RISBibTeXText

PMID: 12524298

DOI: 10.1016/s0006-3495(03)74865-6


Related references

Energy transfer in the plant antenna complexes LHCII and CP29 of spinach studied by three pulse echo peakshift. Photosynthesis Research 69(1-3): 224-225, 2001

Energy transfer between xanthophylls and chlorophylls in LHCII, CP24, CP26 and CP29 complexes of higher plants. Biophysical Journal 80(1 Part 2): 428a-429a, 2001

Carotenoid-to-chlorophyll energy transfer in recombinant major light-harvesting complex (LHCII) of higher plants. I. Femtosecond transient absorption measurements. Biophysical Journal 80(2): 901-915, 2001

Monomeric light harvesting complexes enhance excitation energy transfer from Lhcii to Psii and control their lateral spacing in thylakoids. Biochimica et Biophysica Acta (Bba) - Bioenergetics, 2019

Nature of Disorder and Inter-Complex Energy Transfer in Lh2 at Room Temperature: A Three Pulse Photon Echo Peak Shift Study. The Journal of Physical Chemistry A 106(33): 7573-7578, 2002

Energy transfer between surface-immobilized light-harvesting chlorophyll a/b complex (LHCII) studied by surface plasmon field-enhanced fluorescence spectroscopy (SPFS). Langmuir 26(22): 17315-17321, 2010

Energy transfer in LHCII monomers at 77K studied by sub-picosecond transient absorption spectroscopy. Biochemistry 36(49): 15262-8, 1997

Energy transfer in the B800 ring of light harvesting antenna LH2 of purple bacteria Rps acidophila and Rs molischianum probed by three pulse echo peakshift. Greve, J , Pupels, G J , Otto, C Spectroscopy of biological molecules: New directions 191-193, 1999

Effect of Pulse Shaping on Observing Coherent Energy Transfer in Single Light-Harvesting Complexes. Journal of Physical Chemistry. B 120(45): 11637-11643, 2016

Ultrafast excitation energy transfer and exciton-exciton annihilation processes in isolated light harvesting complexes of photosystem II from spinach at 293 K and 12 K. Photochemistry & Photobiology 61(5 Suppl. ): 85S, 1995

Energy transfer pathways in light-harvesting complexes of purple bacteria as revealed by global kinetic analysis of two-dimensional transient spectra. Journal of Physical Chemistry. B 117(38): 11349-11362, 2013

Spectroscopic characterization of the spinach Lhcb4 protein (CP29), a minor light-harvesting complex of photosystem II. European Journal of Biochemistry 262(3): 817-823, 1999

Characterization of light harvesting mutants of rhodopseudomonas sphaeroides 1. measurement of the efficiency of energy transfer from light harvesting complexes to the reaction center. Archives of Biochemistry and Biophysics 236(1): 130-139, 1985

FDMR of Carotenoid and Chlorophyll triplets in light-harvesting complex LHCII of spinach. Applied Magnetic Resonance 3(5): 859-872, 1992

Rate of carotenoid triplet formation in solubilized light-harvesting complex II (LHCII) from spinach. Biophysical Journal 75(6): 3143-3153, 1998