Braarudosphaera bigelowii

Dodecahedron shaped coccolithophore

Braarudosphaera bigelowii
Temporal range: Late Cretaceous–present
PreꞒ
Ꞓ
O
S
D
C
P
T
J
K
Pg
N
Scientific classification
Domain:
Eukaryota
(unranked):
Haptophyta
Class:
Prymnesiophyceae
Order:
Coccosphaerales
Family:
Braarudosphaeraceae
Genus:
Braarudosphaera
Species:
B. bigelowii
Binomial name
Braarudosphaera bigelowii
(Gran & Braarud) Deflandre[1]

Braarudosphaera bigelowii is a coastal coccolithophore in the fossil record going back 100 million years. The family Braarudosphaeraceae consist of single-celled coastal phytoplanktonic algae with calcareous scales with five-fold symmetry, called pentaliths. With 12 sides, it has a regular dodecahedral structure, approximately 10 micrometers across.[2][3]

(A) SEM image of a cell of B. bigelowii surrounded by 12 pentaliths. A pentalith (calcareous scale of the Braarudosphaeraceae) indicated by the blue open pentagon consists of five trapezoidal segments. Black arrow indicates "side length of the pentalith" where the measurements were conducted. (B) SEM image of pentalith of B. bigelowii (proximal side). (C) Close up of proximal side in previous image showing laminar structure. (D) – (F) light microscope images of three different specimens.[2]

B. bigelowii is reported to have a nitroplast organelle, originated some 100 million years ago from a cyanobacterial endosymbiont called UCYN-A2, which allows B. bigelowii to fix nitrogen and convert it into compounds useful for cell growth.[4][5][6] This phenomenon is previously known from diatoms in the family Rhopalodiaceae, where a nitrogen fixing and non-photosynthetic cyanobacterial endosymbiont, a diazoplast, which provides the photosynthetic host cell with nitrogen.[7][8]

The genus name Braarudosphaera is in honour of Norwegian botanist Trygve Braarud (1903–1985). He specialized in marine biology, and was affiliated with the University of Oslo.[9]

References

  1. ^ Guiry, M.D.; Guiry, G.M. "Braarudosphaera bigelowii". AlgaeBase. World-wide electronic publication, National University of Ireland, Galway.
  2. ^ a b Hagino, K., Onuma, R., Kawachi, M. and Horiguchi, T. (2013) "Discovery of an endosymbiotic nitrogen-fixing cyanobacterium UCYN-A in Braarudosphaera bigelowii (Prymnesiophyceae)". PLoS One, 8(12): e81749. doi:10.1371/journal.pone.0081749.
  3. ^ Baisas, Laura (18 April 2024). "For the first time in one billion years, two lifeforms truly merged into one organism". Popular Science. Retrieved 19 April 2024.
  4. ^ Massana, Ramon (12 April 2024). "The nitroplast: A nitrogen-fixing organelle". Science. 384 (6692): 160–161. doi:10.1126/science.ado8571. ISSN 0036-8075. PMID 38603513. Archived from the original on 15 April 2024. Retrieved 15 April 2024.
  5. ^ Wong, Carissa (11 April 2024). "Scientists discover first algae that can fix nitrogen — thanks to a tiny cell structure". Nature. doi:10.1038/d41586-024-01046-z.
  6. ^ "Scientists Discover First Nitrogen-Fixing Organelle". Berkeley Lab News Center. 17 April 2024.
  7. ^ Moulin, Solène L Y; Frail, Sarah; Braukmann, Thomas; Doenier, Jon; Steele-Ogus, Melissa; Marks, Jane C; Mills, Matthew M; Yeh, Ellen (15 April 2024). "The endosymbiont of Epithemia clementina is specialized for nitrogen fixation within a photosynthetic eukaryote". ISME Communications. doi:10.1093/ismeco/ycae055.
  8. ^ "Genomic divergence within non-photosynthetic cyanobacterial endosymbionts in rhopalodiacean diatoms". www.ncbi.nlm.nih.gov. PMC 5638926. PMID 29026213. Retrieved 25 April 2024.
  9. ^ Burkhardt, Lotte (2022). Eine Enzyklopädie zu eponymischen Pflanzennamen [Encyclopedia of eponymic plant names] (pdf) (in German). Berlin: Botanic Garden and Botanical Museum, Freie Universität Berlin. doi:10.3372/epolist2022. ISBN 978-3-946292-41-8. Archived from the original on 31 August 2023. Retrieved 27 January 2022.

External links

Wikispecies has information related to Braarudosphaera bigelowii.
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Taxon identifiers
Braarudosphaera bigelowii