caa a22 4500 445889624 CHVBK 20180317145611.0 cr unu---uuuuu 170323e20110101xx s 000 0 eng 10.1007/s11120-010-9605-1 doi (NATIONALLICENCE)springer-10.1007/s11120-010-9605-1 Gantt Elisabeth Department of Cell Biology and Molecular Genetics, University of Maryland, 20742, College Park, MD, USA aut Oxygenic photosynthesis and the distribution of chloroplasts [Elektronische Daten] [Elisabeth Gantt] The integrated functioning of two photosystems (I and II) whether in cyanobacteria or in chloroplasts is the outstanding sign of a common ancestral origin. Many variations on the basic theme are currently evident in oxygenic photosynthetic organisms whether they are prokaryotes, unicellular, or multicellular. By conservative estimates, oxygenic photosynthesis has been around for at least ca. 2.2-2.7 billions years, consistent with cyanobacteria-type microfossils, biomarkers, and an atmospheric rise in oxygen to less than 1.0% of the present concentration. The presumptions of chloroplast formation by the cyanobacterial uptake into a eukaryote prior to 1.6BYa ago are confounded by assumptions of host type(s) and potential tolerance of oxygen toxicity. The attempted dating and interrelationships of particular chloroplasts in various plant or animal lineages has relied heavily on phylogenomic analysis and evaluations that have been difficult to confirm separately. Many variations occur in algal groups, involving the type and number of accessory pigments, and the number(s) of membranes (2-4) enclosing a chloroplast, which can both help and complicate inferences made about early or late origins of chloroplasts. Integration of updated phylogenomics with physiological and cytological observations remains a special challenge, but could lead to more accurate assumptions of initial and extant endosymbiotic event(s) leading toward stable chloroplast associations. Springer Science+Business Media B.V., 2010 Chloroplast types nationallicence Cyanobacteria nationallicence Eukaryotic algae nationallicence Nucleomorph nationallicence Reaction centers nationallicence BYa : Billion years ago nationallicence Chl : Chlorophyll nationallicence EGT : Endosymbiotic gene transfer nationallicence HGT : Horizontal (lateral) gene transfer nationallicence OEC : Oxygen evolving complex nationallicence PAL : Present atmospheric level (of oxygen) nationallicence PSI, PSII : Photosystem I, Photosystem II, respectively nationallicence Photosynthesis Research Springer Netherlands 107/1(2011-01-01), 1-6 0166-8595 107:1<1 2011 107 11120 https://doi.org/10.1007/s11120-010-9605-1 text/html Onlinezugriff via DOI 1 editorial jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11120-010-9605-1 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Gantt Elisabeth Department of Cell Biology and Molecular Genetics, University of Maryland, 20742, College Park, MD, USA aut NATIONALLICENCE 773 0- Photosynthesis Research Springer Netherlands 107/1(2011-01-01), 1-6 0166-8595 107:1<1 2011 107 11120 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer