title: High photochemical trapping efficiency in Photosystem I from the red clade algae Chromera velia and Phaeodactylum tricornutum.
abstract: In the present work, we report the first comparative spectroscopic investigation between Photosystem I (PSI) complexes isolated from two red clade algae. Excitation energy transfer was measured in PSI from Chromera velia, an alga possessing a split PsaA protein, and from the model diatom Phaeodactylum tricornutum. In both cases, the estimated effective photochemical trapping time was in the 15-25ps range, i.e. twice as fast as higher plants. In contrast to green phototrophs, the trapping time was rather constant across the whole emission spectrum. The weak wavelength dependence was attributed to the limited presence of long-wavelength emitting chlorophylls, as verified by low temperature spectroscopy. As the trapping kinetics of C. velia PSI were barely distinguishable from those of P. tricornutum PSI, it was concluded that the scission of PsaA protein had no significant impact on the overall PSI functionality. In conclusion, the two red clade algae analysed here, carried amongst the most efficient charge separation so far reported for isolated Photosystems.
authors.affiliation: Centre Algatech, Institute of Microbiology, Academy of Sciences of the Czech Republic, Opatovický mlýn, 379 81 Třeboň, Czech Republic.
authors.forename: Erica
authors.initials: E
authors.lastname: Belgio
authors.affiliation: Photosynthesis Research Unit, Centro per la Biologia Cellulare e Molecolare delle Piante, Via Celoria 26, 20133 Milano, Italy. Electronic address: stefano.santabarbara@cnr.it.
authors.forename: Stefano
authors.initials: S
authors.lastname: Santabarbara
authors.affiliation: Biology Centre CAS, Branišovská 31, 370 05 České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic.
authors.forename: David
authors.initials: D
authors.lastname: Bína
authors.affiliation: Centre Algatech, Institute of Microbiology, Academy of Sciences of the Czech Republic, Opatovický mlýn, 379 81 Třeboň, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic.
authors.forename: Eliška
authors.initials: E
authors.lastname: Trsková
authors.affiliation: Biology Centre CAS, Branišovská 31, 370 05 České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic.
authors.forename: Miroslava
authors.initials: M
authors.lastname: Herbstová
authors.affiliation: Centre Algatech, Institute of Microbiology, Academy of Sciences of the Czech Republic, Opatovický mlýn, 379 81 Třeboň, Czech Republic.
authors.forename: Radek
authors.initials: R
authors.lastname: Kaňa
authors.affiliation: Photosynthesis Research Unit, Centro per la Biologia Cellulare e Molecolare delle Piante, Via Celoria 26, 20133 Milano, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Zucchelli
authors.affiliation: Centre Algatech, Institute of Microbiology, Academy of Sciences of the Czech Republic, Opatovický mlýn, 379 81 Třeboň, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 31, 37005 České Budějovice, Czech Republic. Electronic address: prasil@alga.cz.
authors.forename: Ondřej
authors.initials: O
authors.lastname: Prášil
mesh_terms: D056893:Alveolata / Q000378:metabolism*; D002734:Chlorophyll / Q000378:metabolism; D017377:Diatoms / Q000378:metabolism; D004735:Energy Transfer / Q000502:physiology; D007700:Kinetics; D045342:Light-Harvesting Protein Complexes / Q000378:metabolism; D045331:Photosystem I Protein Complex / Q000378:metabolism*; D000461:Rhodophyta / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
chemical_list: D045342:Light-Harvesting Protein Complexes; D045331:Photosystem I Protein Complex; D002734:Chlorophyll
keywords: Chromera velia; Fluorescence decay; Phaeodactylum tricornutum; Photochemical yield; Photosystem I; Red clade algae; Red spectral forms