Cryptophyceae sp. CCMP2045, a likely conspecific of Cryptophyceae sp. CCMP2293. Photo by Andreas Norlin and Niels Daugbjerg at Københavns Universite.

CCMP2293 has been sequenced as part of the Arctic Chromist project which includes 5 nanoflagellates from divergent lineages. All of these algae were isolated from the same region of the Arctic and a goal of the project is to investigate the potential for genetic signatures of algae living under perennially cold conditions.  While most of the samples for isolation were collected during the Arctic summer with 24h of light as part of the North Water Polynya Study (NOW) in Northern Baffin Bay, CCMP2293 was collected from the upper water column on 10 April from Northern Baffin Bay which is between Greenland and Ellesmere Island when the temperature was -1.7 °C. As with the other algae CCMP2293 was isolated using a dilution technique where subsamples of starting sample were placed initially in 6- or 12-well multiwell plates and transferred to different media when swimming cells were detected using an inverted microscope. Resulting unialgal cultures have been maintained in natural aged and filtered seawater amended with standard media.
 
The cryptophyte CCMP2293 was originally isolated from a water sample collected from ca. 10 m depth in April 1998 (78.5922 °N; 74.4922 °W). The water was collected directly from the Niskin bottle mounted on a CTD Rosette system on the Canadian Coast Icebreaker Pierre Radisson and placed into a 50 ml Falcon tube and kept at 4 °C in the dark until returned to the land based laboratory within  3 days.   The culture has been maintained in seawater at a salinity of 30.
 
Cryptophyceae are evolutionarily of interest because of their secondary nucleus, the nucleomorph, derived from the endosymbiosis of another microbial alga. The chloroplast from this endosymbiotic event is also unusual because of the presence of phycobilproteins. Current cryptophyte taxonomy is based on cell morphology and the character of the phycobiliproteins, which tend to give the cultures either a reddish of blue-greenish color. About half of known species occur in freshwaters, with the rest thought to be marine, with evidence that at least some species are euryhaline.  It is also now generally accepted that these algae can engulf bacteria and are mixotrophic. Cryptophytes are frequent partners in kleptoplastidic events and enslaved by several ciliate and dinoflagellate taxa.

The 18S rRNA phylogeny indicates that CCMP2293 is identical or very closely related to another cryptophyte isolated from the Northwater Polynya in June 1998 (CCMP2045, from 11 m depth 76.3208 °N; 75.8172 °W), but further comparative taxonomy at the level of ITS and other marker genes is needed to confirm if they are the same species. Both branch apart from available cultured described species, but morphologically they are closest to the genus Falcomonas.   

Additional transcriptomes are available from the Marine Microbial Eukaryote Transcription Project. CCMP2293 was grown under different culture conditions with urea or nitrate as a nitrogen source, and under low (18) and high salinity (36). Currently the culture is being taxonomically described and a complete description will be available on publication.

(written by C. Lovejoy, who initially isolated the culture and has maintained it in culture)