Isolation and characterization of CAC antenna proteins and photosystem I supercomplex from the cryptophytic alga Rhodomonas salina

Abstract

In the present paper, we report an improved method combining sucrose density gradient with ion‐exchange chromatography for the isolation of pure chlorophyll a/c antenna proteins from the model cryptophytic alga Rhodomonas salina. Antennas were used for in vitro quenching experiments in the absence of xanthophylls, showing that protein aggregation is a plausible mechanism behind non‐photochemical quenching in R. salina. From sucrose gradient, it was also possible to purify a functional photosystem I supercomplex, which was in turn characterized by steady‐state and time‐resolved fluorescence spectroscopy. R. salina photosystem I showed a remarkably fast photochemical trapping rate, similar to what recently reported for other red clade algae such as Chromera velia and Phaeodactylum tricornutum. The method reported therefore may also be suitable for other still partially unexplored algae, such as cryptophytes.

Structure and distinct supramolecular organization of a PSII-ACPII dimer from a cryptophyte alga Chroomonas placoidea

“…The pigment-protein complexes of PSI and PSII of cryptophytes are localized in thylakoid membranes as monomers for PSI and as dimers for PSII, respectively, similar to those seen in other algae and higher plants 30 , 31 . The structure of PSI-light-harvesting antenna (LHCI) supercomplex from a cryptophyte alga Chroomonas placoidea ( C. placoidea ) has been determined by cryo-electron microscopy recently and reveals detailed composition and structural features of the PSI-LHCI complex 32 .…”

Intraspecific variations in macronutrient, amino acid, and fatty acid composition of mass-cultured Teleaulax amphioxeia (Cryptophyceae) strains

“…For example, TPG clade species including strains of Teleaulax genus with particularly high eicosapentaenoic acid (EPA) contents are expected to be excellent food for the enrichment of prey zooplankton (Peltomaa et al 2018). RHO clade species are also known to have photophysically very efficient lightharvesting plastid systems (Doust et al 2006, Marin et al 2011, Kim et al 2015 with the key proteins such as phycobiliproteins, chlorophyll a/c antenna proteins, and photosystem I supercomplex in Rhodomonas salina (Kuthanová Trsková et al 2019).…”

Differential responses of green-synthesized iron nano-complexes in mitigating bicarbonate stress in almond trees

“…The results indicated that the activity of this enzyme was governed by Fe supply to plants. Leaf proteins play a critical role in supporting and protecting photosynthetic pigments and preserving the integrity of the chloroplasts [ 71 , 72 ]. The majority of leaf proteins accumulate in the chloroplasts in association with chlorophylls [ 3 ].…”