Picobiliphytes: A Marine Picoplanktonic Algal Group with Unknown Affinities to Other Eukaryotes

Department of Biology, Laval University, Quebec City, Quebec, Canada
Science (Impact Factor: 31.48). 02/2007; 315(5809):253-5. DOI: 10.1126/science.1136264
Source: PubMed

ABSTRACT Environmental sequencing has revealed unimagined diversity among eukaryotic picoplankton. A distinct picoplanktonic algal group, initially detected from 18S ribosomal DNA (rDNA) sequences, was hybridized with rRNA-targeted probes, detected by tyramide signal amplification-fluorescent in situ hybridization, and showed an organelle-like body with orange fluorescence indicative of phycobilins. Using this fluorescence signal, cells were sorted by flow cytometry and probed. Hybridized cells contained a 4',6'-diamidino-2-phenylindole-stained organelle resembling a plastid with a nucleomorph. This suggests that they may be secondary endosymbiotic algae. Pending the isolation of living cells and their formal description, these algae have been termed picobiliphytes.

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