Gloeomargarita lithophora, a cyanobacterium, is the proposed closest present day relative of all chloroplasts[1] (except for the independently evolved in the amoeboid Paulinella chromatophora). The ancient relative of Gloeomargarita's was engulfed by a eukaryotic host in a singule endosymbiotic event around 1900-1400 million years ago.[2][3] The origin of plastids by endosymbiosis signifies the beginning of photosynthesis in eukaryotes,[4] and as such their evolutionary relationship to Gloeomargarita lithophora, as the sister group,[3] is of high importance to the evolutionary history of endosymbiotic organelles and photosynthesis.
| Gloeomargarita lithophora | |
|---|---|
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| Image of G. lithophora cells showing carbonate and polyphosphate inclusions taken using annular dark-field imaging (HAADF-STEM). | |
| Scientific classification | |
| Domain: | |
| Phylum: | |
| Order: | Gloeomargaritales
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| Family: | Gloeomargaritaceae
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| Genus: | |
| Species: | G. lithophora
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| Binomial name | |
| Gloeomargarita lithophora | |
Description
editG. lithophora was first isolated in 2007 from microbiolate samples taken from alkaline Lake Alchichica (Mexico). These samples were maintained in a lab aquarium and G. lithophora was isolated from biofilm that occurred within the aquarium. G. lithophora are gram-negative, unicellular rods with oxygenic photoautotrophic metabolism and gliding motility. They contain chlorophyll a and phycocyanin and photosynthetic thylakoids located peripherally. Cells are 1.1 μm wide and 3.9 μm long on average. Growth occurred in both liquid and solid BG-11 growth media, as well as in alkaline water. Optimal growth temperature is 25 °C and optimal growth pH is 8–8.5.[5]
Bioremediation
editSome evidence suggests that Gloeomargarita lithophora could serve as a biological buffer to treat water contaminated with strontium, barium, or radioactive pollutants such as radium. This could be a useful application of bioremediation.[6][7][8]
References
edit- ^ Sánchez-Baracaldo, Patricia; Raven, John A.; Pisani, Davide; Knoll, Andrew H. (2017-09-12). "Early photosynthetic eukaryotes inhabited low-salinity habitats". Proceedings of the National Academy of Sciences. 114 (37): E7737–E7745. Bibcode:2017PNAS..114E7737S. doi:10.1073/pnas.1620089114. ISSN 0027-8424. PMC 5603991. PMID 28808007.
- ^ Strassert, Jürgen F. H.; Irisarri, Iker; Williams, Tom A.; Burki, Fabien (2021). "A molecular timescale for eukaryote evolution with implications for the origin of red algal-derived plastids". Nature. 12 (1): 1879. Bibcode:2021NatCo..12.1879S. doi:10.1038/s41467-021-22044-z. PMC 7994803. PMID 33767194.
- ^ a b Betts, Holly C.; Puttick, Mark N.; Clark, James W.; Williams, Tom A.; Donoghue, Philip C. J.; Pisani, Davide (2018-08-20). "Integrated genomic and fossil evidence illuminates life's early evolution and eukaryote origin". Nature Ecology & Evolution. 2 (10): 1556–1562. doi:10.1038/s41559-018-0644-x. ISSN 2397-334X. PMC 6152910. PMID 30127539.
- ^ Gould, Sven B.; Waller, Ross F.; McFadden, Geoffrey I. (2008). "Plastid Evolution". Annual Review of Plant Biology. 59 (1): 491–517. doi:10.1146/annurev.arplant.59.032607.092915. PMID 18315522.
- ^ Moreira, David; Tavera, Rosaluz; Benzerara, Karim; Skouri-Panet, Fériel; Couradeau, Estelle; Gérard, Emmanuelle; Loussert Fonta, Céline; Novela, Eberto; Zivanovic, Yvan; López-García, Purificación (2017-04-01). "Description of Gloeomargarita lithophora gen. nov., sp. nov., a thylakoid-bearing basal-branching cyanobacterium with intracellular carbonates, and proposal for Gloeomargaritales ord. nov". International Journal of Systematic and Evolutionary Microbiology. 67 (3): 653–658. doi:10.1099/ijsem.0.001679. PMC 5669459. PMID 27902306.
- ^ Blondeau, Marine; Benzerara, Karim; Ferard, Céline; Guigner, Jean-Michel; Poinsot, Mélanie; Coutaud, Margot; Tharaud, Mickaël; Cordier, Laure; Skouri-Panet, Fériel (20 April 2018). "Impact of the cyanobacterium Gloeomargarita lithophora on the geochemical cycles of Sr and Ba". Chemical Geology. 483: 88–97. Bibcode:2018ChGeo.483...88B. doi:10.1016/j.chemgeo.2018.02.029. ISSN 0009-2541. Retrieved 10 April 2020.
- ^ Mehta, Neha; Bougoure, Jeremy; Kocar, Benjamin D.; Duprat, Elodie; Benzerara, Karim (2022-04-08). "Cyanobacteria Accumulate Radium ( 226 Ra) within Intracellular Amorphous Calcium Carbonate Inclusions". ACS ES&T Water. 2 (4): 616–623. doi:10.1021/acsestwater.1c00473. ISSN 2690-0637. S2CID 247456505.
- ^ Mehta, Neha; Benzerara, Karim; Kocar, Benjamin D.; Chapon, Virginie (2019-11-05). "Sequestration of Radionuclides Radium-226 and Strontium-90 by Cyanobacteria Forming Intracellular Calcium Carbonates". Environmental Science & Technology. 53 (21): 12639–12647. Bibcode:2019EnST...5312639M. doi:10.1021/acs.est.9b03982. ISSN 0013-936X. PMID 31584265. S2CID 203661666.