title: Heliobacterium and the origin of chrysoplasts.
abstract: Chrysoplasts, golden-yellow and brown photosynthetic membrane-bounded plastids, photosynthetic organelles of algae such as phaeophytes (brown seaweeds), bacillariophytes (diatoms) and chrysophytes (golden-yellow algae including silicoflagellates), are hypothesized to have originated from brownish photoheterotrophic bacteria such as the newly discovered anaerobic nitrogen-fixing Heliobacterium. The consequences of this hypothesis as well as the data required to verify or disprove it are presented.
mesh_terms: D005075:Biological Evolution; D002734:Chlorophyll / Q000378:metabolism; D002736:Chloroplasts / Q000648:ultrastructure; D056890:Eukaryota / Q000378:metabolism / Q000648:ultrastructure; D006090:Gram-Negative Bacteria / Q000378:metabolism / Q000648:ultrastructure*; D008854:Microscopy, Electron; D008954:Models, Biological; D009586:Nitrogen Fixation; D009940:Organoids / Q000648:ultrastructure*
chemical_list: D002734:Chlorophyll