Pigment compositions are linked to the habitat types in dinoflagellates

Abstract

Compared to planktonic species, benthic dinoflagellates living in sandy beach or seafloor are a little known about ecology, physiology, even their existences. In a previous study, we discovered 13 2 ,17 3 -cyclopheophorbide a enol (cPPB-aE) from sand-dwelling benthic dinoflagellates. This enol had never been detected in phytoplankton despite it is a chlorophyll a catabolite. We speculated from this discovery that habitat selection might be linked to pigment compositions in dinoflagellates. To test the hypothesis of habitat selection linking to pigment compositions, we conducted extensive analysis of pigments with high performance liquid chromatography (HPLC) for 40 species using 45 strains of dinoflagellates including three habitat types; sand-dwelling benthic forms, tidal pool inhabitants and planktonic species.Those 40 dinoflagellates are also able to distinguished into two types based on their chloroplast origins; red alga-derived secondary chloroplasts and diatom-derived tertiary ones.By plotting the pigments profiles onto three habitats, we noticed that twelve pigments including cPPB-aE were found to occur only in benthic sand-dwelling species of red alga-derived type. The similar tendency was also observed in dinoflagellates with diatom-derived chloroplasts, i.e. additional sixteen pigments including chl c 3 were found only in sand-dwelling forms. This is the first report of the occurrence of chl c 3 in dinoflagellate 3 with diatom-derived chloroplasts. These results clarify the far greater diversity of pigments are produced by the dinoflagellates living in sand regardless of chloroplast types relative to those of planktonic and tidal pool forms. Dinoflagellates seem to produce a part of their pigments in response to their habitats.

Identification of Highly Divergent Diatom-Derived Chloroplasts in Dinoflagellates, Including a Description of Durinskia kwazulunatalensis sp. nov. (Peridiniales, Dinophyceae)

“…Galeidinium rugatum (AB195668, strain HG249, collected in Palau) and the two unidentified coccoid dinotoms (one species, strain HG180, collected from Japan, and another, strain HG204, from South Africa) formed a single clade (Group 5) with 100% BS value. Although closely related, the two coccoid forms are considered to represent independent species from each other because of their distinguishable morphologies (Yamada et al 2015). The nucleotide divergence of the two coccoid species relative to G. rugatum (over 1726 bp) was 1.27% (for unidentified coccoid dinotom 1) and 1.85% (for unidentified coccoid dinotom 2).…”

Plagiodinium ballux sp. nov. (Dinophyceae), a deep (36 m) sand dwelling dinoflagellate from subtropical Japan

“…The sequence LC054937, was linked with only a single color micrograph of strain HG225 (Yamada et al . ), the cell of which showed a morphology typical of P. belizeanum. The morphology of the strain linked with the registered sequence KX008973 (Wakeman et al .…”

“…The small subunit ribosomal RNA gene (SSU rDNA) sequence for the strain HG177 has been deposited in DDBJ/GenBank by Yamada et al . () (Accession No. LC054938 as Plagiodinium sp.…”

Re‐investigation of Gymnodinium natalense (Dinophyceae), a tidal pool dinoflagellate from South Africa and the proposal of a new combination Ansanella natalensis

“…, Yamada et al . ), albeit this photosynthetic pigment composition is one shared by many dinoflagellates (Yamada et al . ).…”

“…In addition to strains CW‐19 and CX‐13, we included the sequence of strain CX‐7 (1797 base pairs) in our alignment (accession number LC054923, registered as Biecheleria natalensis ), isolated at the same time as the other two strains and used this material for photosynthetic pigment analysis (Yamada et al . ).…”