Project description:Photosynthetic organisms harvest light for energy. Some eukaryotic algae have specialized in harvesting far-red light by tuning chlorophyll a absorption through a mechanism still to be elucidated. Here, we combined optically detected magnetic resonance and pulsed electron paramagnetic resonance measurements on red-adapted light-harvesting complexes, rVCP, isolated from the freshwater eustigmatophyte alga Trachydiscus minutus to identify the location of the pigments responsible for this remarkable adaptation. The pigments have been found to belong to an excitonic cluster of chlorophylls a at the core of the complex, close to the central carotenoids in L1/L2 sites. A pair of structural features of the Chl a403/a603 binding site, namely the histidine-to-asparagine substitution in the magnesium-ligation residue and the small size of the amino acid at the i-4 position, resulting in a [A/G]xxxN motif, are proposed to be the origin of this trait. Phylogenetic analysis of various eukaryotic red antennae identified several potential LHCs that could share this tuning mechanism.
2024-10-04 | MSV000096023 | MassIVE
Project description:Phylogenetic position of Nesodexia
Project description:<p><em>Dalbergia odorifera</em> T. Chen, an indigenous species in Hainan Island, China, had high economic and cultural values. Its sapwood was light yellow, while, heartwood was rich in colors of red, yellow, orange and black. The colorful oily deposits were found in the vessels, fibers and parenchyma cells of the heartwood. The contents of extractives, flavonoid and anthocyanin in heartwood were found to be 11.83%, 34.88 mg/g and 705.84 μg/g, 3.29 times, 12.37 times and 9.51 times higher than that of sapwood, respectively. More extractives, flavonoid, anthocyanin appeared in the transition zone in heartwood area position with abundant metabolites. Among them, flavonoids were 26.2%. The relative content of metabolites such as anthocyanins, chalcone, flavone and anthraquinone increased greatly in heartwood. The formation of red-yellow-orange mixed color of <em>Dalbergia odorifera</em> heartwood was related to these metabolites.</p>
Project description:We combined new data with previously published data (PMID: 25877615, 26811443, 29379068, 18292342, 24297229, 27302840, 24395773 and 30846778) to compare phylogenetic relationships of the Ami and Yami aborigenes of Taiwan to groups from mainland Southeast Asia, island Southeast Asia and Oceania.
