Location:

Lab work performed at University of Alabama at Birmingham and University of Texas at Austin; Samples collected from Guam, California, and Gulf of Mexico.

Sampling and analytical procedures:

 Cultures were obtained from sites in Guam, California, and the Gulf of Mexico near Florida. Cells were isolated from collections made primarily by plankton net with 20 m mesh or by collection of the top millimeters of sediment from the benthos. Individual cells were isolated by glass Pasteur pipet (Andersen) into 15x100 mm glass test tubes in approximately 12 mL of liquid f/2 medium with double the normal concentration of silica (Guillard, Andersen) at a salinity of 32-35 ppt. The f/2 base was seawater collected from the Texas coast of the Gulf of Mexico and passed through a 0.22 um filter. Isolates were maintained under natural light from a north facing window between 20-24oC, or in a Percival growth chamber on a 12:12 light:dark cycle at 27oC in the case of the isolates from Guam. Once unialgal growth was confirmed by microscopy, strains were maintained in triplicate with cells (approximately 0.25 mL) from one tube transferred to three fresh media tubes every 3-4 months.

During the strain transfer cycle, one replicate tube was harvested by Pasteur pipet into a 1.5 mL microcentrifuge tube and centrifuged in an Eppendorf 5414 C microcentrifuge at 8,000 rpm for 10 minutes. Liquid media was decanted off the pellet, and the pellet was stored at -80oC until DNA extraction. DNA was extracted from the pellets using a MoBio Powersoil DNA kit, following the manufacturers protocol.

The V4 region of the bacterial 16S rRNA gene was amplified using bar-coded PCR primers (Caporaso), purified by gel electrophoresis, and then sequenced using the Illumina MiSeq platform. Quality control and sequence analysis was performed in mothur according to the mothur MiSeq SOP protocol (Schlosss, Kozich).

Sequence data is available from the NCBI SRA archive, BioProject PRJNA706454.

Species List (ScientificName,AphiaID)

Astrosyne radiata,837899
Roundia cardiophora,627356
Florella pascuensis,646734
Triceratium dubium,418600
Striatella unipunctata,149177
Hanicella moenia,842549
Paralia longispina,708079
Astrosyne radiata,837899
Neosynedra provincialis,175369
Leptocylindrus danicus,149106