Cryptomonad

Source: Wikipedia, the free encyclopedia.
"Cryptophyte" redirects here. For other uses, see Cryptophyte (disambiguation).

Cryptomonads
Rhodomonas salina
Eukaryota
)
Domain:
Eukaryota
(unranked):
Hacrobia
(unranked):
Cryptista
Phylum:
Cryptophyta

Classes & orders
Synonyms

The cryptomonads (or cryptophytes)

10–50 μm in size and flattened in shape, with an anterior groove or pocket. At the edge of the pocket there are typically two slightly unequal flagella
.

Some may exhibit

mixotrophy.[3]

Characteristics

flagella, 11-invagination, 12-lipid globules, 13-ejectosomes, 14-mitochondrion, 15-pyrenoid, 16-Golgi apparatus, 17-endoplasmic reticulum, 18-chloroplast-endoplasmic reticulum
.

Cryptomonads are distinguished by the presence of characteristic extrusomes called ejectosomes, which consist of two connected spiral ribbons held under tension.[4] If the cells are irritated either by mechanical, chemical or light stress, they discharge, propelling the cell in a zig-zag course away from the disturbance. Large ejectosomes, visible under the light microscope, are associated with the pocket; smaller ones occur underneath the periplast, the cryptophyte-specific cell surrounding.[5][6]

Except for the class

red alga.[8] However, the plastids are very different from red algal plastids: phycobiliproteins are present but only in the thylakoid lumen and are present only as phycoerythrin or phycocyanin. In the case of Rhodomonas, the crystal structure has been determined to 1.63 Å;[9]
and it has been shown that the alpha subunit bears no relation to any other known phycobiliprotein.

A few cryptomonads, such as

mastigonemes, formed within the endoplasmic reticulum and transported to the cell surface. Small scales may also be present on the flagella and cell body. The mitochondria have flat cristae, and mitosis is open; sexual reproduction
has also been reported.

Classification

Cryptophytes under SEM
light microscope
Further information: Wikispecies:Cryptophyceae

The first mention of cryptomonads appears to have been made by

glaucophytes.[13] The sister group to the cryptomonads is likely the kathablepharids (also referred to as katablepharids), a group of flagellates that also have ejectisomes.[14]

One suggested grouping is as follows: (1)

Falcomonas daucoides.[15]

References

  1. ISBN 978-0-632-04761-1
    .
  2. PMID 18397952
    .
  3. ^ "Cryptophyta - the cryptomonads". Archived from the original on 2011-06-10. Retrieved 2009-06-02.
  4. ISBN 9780321559654
    .
  5. PMID 6155157
    .
  6. PMID 6470985
    .
  7. ^ Nuclear genome sequence of the plastid-lacking cryptomonad Goniomonas avonlea provides insights into the evolution of secondary plastids
  8. PMID 11323671
    .
  9. PMID 10430868
    .
  10. ^ Novarino, G. (2012). "Cryptomonad taxonomy in the 21st century: The first 200 years". Phycological Reports: Current Advances in Algal Taxonomy and Its Applications: Phylogenetic, Ecological and Applied Perspective: 19–52. Retrieved 2018-10-16.
  11. PMID 30482201
    .
  12. PMID 21810989
    .
  13. PMID 26817772
    .
  14. doi:10.3389/fevo.2020.00140
    .
  15. ^ "Cryptomonads". Retrieved 2009-06-24.

External links

Retrieved from "https://en.wikipedia.org/w/index.php?title=Cryptomonad&oldid=1178654181"