RRC ID 79132
Author Coale TH, Loconte V, Turk-Kubo KA, Vanslembrouck B, Mak WKE, Cheung S, Ekman A, Chen JH, Hagino K, Takano Y, Nishimura T, Adachi M, Le Gros M, Larabell C, Zehr JP.
Title Nitrogen-fixing organelle in a marine alga.
Journal Science
Abstract Symbiotic interactions were key to the evolution of chloroplast and mitochondria organelles, which mediate carbon and energy metabolism in eukaryotes. Biological nitrogen fixation, the reduction of abundant atmospheric nitrogen gas (N2) to biologically available ammonia, is a key metabolic process performed exclusively by prokaryotes. Candidatus Atelocyanobacterium thalassa, or UCYN-A, is a metabolically streamlined N2-fixing cyanobacterium previously reported to be an endosymbiont of a marine unicellular alga. Here we show that UCYN-A has been tightly integrated into algal cell architecture and organellar division and that it imports proteins encoded by the algal genome. These are characteristics of organelles and show that UCYN-A has evolved beyond endosymbiosis and functions as an early evolutionary stage N2-fixing organelle, or "nitroplast."
Volume 384(6692)
Pages 217-222
Published 2024-4-12
DOI 10.1126/science.adk1075
PMID 38603509
MeSH Chloroplasts / metabolism Cyanobacteria* / genetics Cyanobacteria* / metabolism Haptophyta* / microbiology Mitochondria* / metabolism Nitrogen* / metabolism Nitrogen Fixation* / genetics Seawater / microbiology Symbiosis
Algae NIES-4399