3iis
From Proteopedia
Structure of the reconstituted Peridinin-Chlorophyll a-Protein (RFPCP)
Structural highlights
FunctionPCP1_AMPCA Water-soluble antenna for capture of solar energy in the blue-green range. Peridinin is an asymmetric carotenoid. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe peridinin-chlorophyll a-protein (PCP) of dinoflagellates is unique among the large variety of natural photosynthetic light-harvesting systems. In contrast to other chlorophyll protein complexes, the soluble PCP is located in the thylakoid lumen, and the carotenoid pigments outnumber the chlorophylls. The structure of the PCP complex consists of two symmetric domains, each with a central chlorophyll a (Chl-a) surrounded by four peridinin molecules. The protein provides distinctive surroundings for the pigment molecules, and in PCP, the specific environment around each peridinin results in overlapping spectral line shapes, suggestive of different functions within the protein. One particular Per, Per-614, is hypothesized to show the strongest electronic interaction with the central Chl-a. We have performed an in vitro reconstitution of pigments into recombinant PCP apo-protein (RFPCP) and into a mutated protein with an altered environment near Per-614. Steady-state and transient optical spectroscopic experiments comparing the RFPCP complex with the reconstituted mutant protein identify specific amino acid-induced spectral shifts. The spectroscopic assignments are reinforced by a determination of the structures of both RFPCP and the mutant by x-ray crystallography to a resolution better than 1.5 A. RFPCP and mutated RFPCP are unique in representing crystal structures of in vitro reconstituted light-harvesting pigment-protein complexes. Identification of a single peridinin sensing Chl-a excitation in reconstituted PCP by crystallography and spectroscopy.,Schulte T, Niedzwiedzki DM, Birge RR, Hiller RG, Polivka T, Hofmann E, Frank HA Proc Natl Acad Sci U S A. 2009 Dec 8;106(49):20764-9. Epub 2009 Nov 23. PMID:19934052[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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