%0 Journal Article %J Scientific Reports %D 2023 %T Bioprospecting for industrially relevant exopolysaccharide-producing cyanobacteria under Portuguese simulated climate %A Cruz, José Diogo %A Delattre, Cédric %A Felpeto, Aldo Barreiro %A Pereira, Hugo %A Pierre, Guillaume %A Morais, João %A Petit, Emmanuel %A Silva, Joana %A Azevedo, Joana %A Elboutachfaiti, Redouan %A Maia, Inês B. %A Dubessay, Pascal %A Michaud, Philippe %A Vasconcelos, Vitor %K Biochemistry %K Biotechnology %K Microbiology %K rcc2380 %X Cyanobacterial exopolysaccharides (EPS) are potential candidates for the production of sustainable biopolymers. Although the bioactive and physicochemical properties of cyanobacterial-based EPS are attractive, their commercial exploitation is limited by the high production costs. Bioprospecting and characterizing novel EPS-producing strains for industrially relevant conditions is key to facilitate their implementation in various biotechnological applications and fields. In the present work, we selected twenty-five Portuguese cyanobacterial strains from a diverse taxonomic range (including some genera studied for the first time) to be grown in diel light and temperature, simulating the Portuguese climate conditions, and evaluated their growth performance and proximal composition of macronutrients. Synechocystis and Cyanobium genera, from marine and freshwater origin, were highlighted as fast-growing (0.1–0.2 g L−1 day−1) with distinct biomass composition. Synechocystis sp. LEGE 07367 and Chroococcales cyanobacterium LEGE 19970, showed a production of 0.3 and 0.4 g L−1 of released polysaccharides (RPS). These were found to be glucan-based polymers with high molecular weight and a low number of monosaccharides than usually reported for cyanobacterial EPS. In addition, the absence of known cyanotoxins in these two RPS producers was also confirmed. This work provides the initial steps for the development of cyanobacterial EPS bioprocesses under the Portuguese climate. %B Scientific Reports %V 13 %P 13561 %G eng %U https://www.nature.com/articles/s41598-023-40542-6 %R 10.1038/s41598-023-40542-6 %0 Journal Article %J The ISME Journal %D 2019 %T Taming chlorophylls by early eukaryotes underpinned algal interactions and the diversification of the eukaryotes on the oxygenated Earth %A Kashiyama, Yuichiro %A Yokoyama, Akiko %A Shiratori, Takashi %A Hess, Sebastian %A Not, Fabrice %A Bachy, Charles %A Gutierrez-Rodriguez, Andres %A Kawahara, Jun %A Suzaki, Toshinobu %A Nakazawa, Masami %A Ishikawa, Takahiro %A Maruyama, Moe %A Wang, Mengyun %A Chen, Man %A Gong, Yingchun %A Seto, Kensuke %A Kagami, Maiko %A Hamamoto, Yoko %A Honda, Daiske %A Umetani, Takahiro %A Shihongi, Akira %A Kayama, Motoki %A Matsuda, Toshiki %A Taira, Junya %A Yabuki, Akinori %A Tsuchiya, Masashi %A Hirakawa, Yoshihisa %A Kawaguchi, Akane %A Nomura, Mami %A Nakamura, Atsushi %A Namba, Noriaki %A Matsumoto, Mitsufumi %A Tanaka, Tsuyoshi %A Yoshino, Tomoko %A Higuchi, Rina %A Yamamoto, Akihiro %A Maruyama, Tadanobu %A Yamaguchi, Aika %A Uzuka, Akihiro %A Miyagishima, Shinya %A Tanifuji, Goro %A Kawachi, Masanobu %A Kinoshita, Yusuke %A Tamiaki, Hitoshi %K Biochemistry %K Biogeochemistry %K Cellular microbiology %K microbial ecology %K RCC164 %K RCC22 %K RCC24 %K RCC375 %K RCC916 %X Extant eukaryote ecology is primarily sustained by oxygenic photosynthesis, in which chlorophylls play essential roles. The exceptional photosensitivity of chlorophylls allows them to harvest solar energy for photosynthesis, but on the other hand, they also generate cytotoxic reactive oxygen species. A risk of such phototoxicity of the chlorophyll must become particularly prominent upon dynamic cellular interactions that potentially disrupt the mechanisms that are designed to quench photoexcited chlorophylls in the phototrophic cells. Extensive examination of a wide variety of phagotrophic, parasitic, and phototrophic microeukaryotes demonstrates that a catabolic process that converts chlorophylls into nonphotosensitive 132,173-cyclopheophorbide enols (CPEs) is phylogenetically ubiquitous among extant eukaryotes. The accumulation of CPEs is identified in phagotrophic algivores belonging to virtually all major eukaryotic assemblages with the exception of Archaeplastida, in which no algivorous species have been reported. In addition, accumulation of CPEs is revealed to be common among phototrophic microeukaryotes (i.e., microalgae) along with dismantling of their secondary chloroplasts. Thus, we infer that CPE-accumulating chlorophyll catabolism (CACC) primarily evolved among algivorous microeukaryotes to detoxify chlorophylls in an early stage of their evolution. Subsequently, it also underpinned photosynthetic endosymbiosis by securing close interactions with photosynthetic machinery containing abundant chlorophylls, which led to the acquisition of secondary chloroplasts. Our results strongly suggest that CACC, which allowed the consumption of oxygenic primary producers, ultimately permitted the successful radiation of the eukaryotes throughout and after the late Proterozoic global oxygenation. %B The ISME Journal %P 1 %8 feb %G eng %U http://www.nature.com/articles/s41396-019-0377-0 %R 10.1038/s41396-019-0377-0