Peridinin chlorophyll-protein complex

Fig. 3 Schematic model of light-harvesting compartments in photosynthetic organisms and their position with respect to the membrane and the reaction centers. RC1(2) Photosystem I(II) reaction centre. Peripheral membrane antennas Chlorosome/FMO in green sulfur and nonsulfur bacteria, phycobilisome (PBS) in cyanobacteria and rhodophytes and peridinin-chlorophyll proteins (PCP) in dyno-phytes. Integral membrane accessory antennas LH2 in purple bacteria, LHC family in all eukaryotes. Integral membrane core antennas B808-867 complex in green nonsulfur bacteria, LH1 in purple bacteria, CP43/CP47 (not shown) in cyanobacteria and all eukaryotes.

A. Structure and Function of the Peridinin-Chlorophyll-Protein (PCP) Complex.233... 

Fig. 5. Crystal structure ofthe A. carterae PCP monomer. (A) stereogram ofthe ribbon model ofthe PCP monomer. The scaffold formed by the helices is likened to a boat the various parts of a boat (bow, stern, deck and keel) are marked. The chromophores in the hydro-phobic cavity ofthe monomer complex are likened to "cargos. (B) stereogram ofthe arrangement of peridinins and chlorophyll in the N-terminal domain [oniy two peridinins ofthe C-terminai domain are shown by thinner iines]. Figure source Hofmann, Wrench, Sharpies, Hiller, Werte and Diederichs (1996) Structural basis of light harvesting by carotenoids Peridinin-chlorophyll-protein from Amphidinlum carterae. Science 272 1789,1790. A color stereogram of (A) kindiy provided by Dr. Eckhard Hofmann and Dr. Wolfram Weite is shown in Color Plate 7.

The CD spectrum of the light-harvesting peridinin (30)-chlorophyll-protein complex from dinoflagellates (56) has recently been used together with fluorescence excitation spectra for interpretation of the molecular topology of this complex (722). 

The molecular topology of the peridinin (30)-chlorophyll-protein complex (122) and of crustacyanin (123 a) has recently been studied and future progress in this field is anticipated. 

Fig. 1 (C) Structure of the complete peridinin-chlorophyll-protein trimer complex from the dinoflagellate Amphidinium carterae. The protein is depicted in ice blue, the carotenoids in red and the chlorophylls in green. Figure kindly produced by Robielyn Hagan from PDB file IPPR using VMD.

Figure 7 Rogue s gallery of structures of peripheral anteima complexes. As labelled these include Chlorosomes from green sulfur bacteria, fused antenna domains of the Photosystem I core, the CP43 and CP47 proteins of Photosystem II, the Fenna-Matthew-Olson (FMO) protein associated with chlorosomes, LHI proteins surrounding a purple bacterial photo synthetic core, the peridinin-chlorophyll a protein of dinoflagellate algae, the LHCI and LHCII proteins found in plants and many algae, and the LHII protein complex that is associated with LHI in purple bacteria...

Koka, P., and P.-S. Song The chromophore topography and binding environment of peridinin-chlorophyll a — protein complexes from marine dinoflagellate algae. Biochim. Biophys. Acta 495, 220 (1977). 

Eukaryotic plants and cyanobacteria. Photosynthetic dinoflagellates, which make up much of the marine plankton, use both carotenoids and chlorophyll in light-harvesting complexes. The carotenoid peridinin (Fig. 23-29), which absorbs blue-green in the 470- to 550-nm range, predominates. The LH complex of Amphidinium carterae consists of a 30.2-kDA protein that forms a cavity into which eight molecules of peridinin but only two of chlorophyll a (Chi a) and two molecules of a galactolipid are bound (Fig. 23-29).268... 

The unique water-soluble peridinin- Chi a-protein (PCP) complexes are found in many dynoflagellates in addition to intrinsic membrane complexes. [64] It contains Chi a and the unusual carotenoid peridinin in stoichiometric ratio of 1 4. Unlike other families of antennas, the main light-harvesting pigments are carotenoids, not chlorophylls. The structure of the PCP consists of a protein that folds into four domains, each of which embeds four peridinin molecules and a single Chi a. The protein then forms trimers, suggested to be located in the lumen [64] in contact with both LHCI and LHCII [66], allowing efficient EET to occur. 

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