Prokaryotic plankton

One of the largest collections of published environmental small subunit rRNA gene clones from any source is that from marine prokaryotic plankton [20]. This dataset currently includes more than 600 identified bacterial clones. A comprehensive analysis of these sequences has shown that identical sequences falling into similar clades are recovered from geographically and ecologically... 

Alderkamp AC, Sintes E, Herndl GJ (2006b) Abundance and activity of major groups of prokaryotic plankton in the coastal North Sea during the wax and wane of a phytoplankton spring bloom. Aquat Microb Ecol 45 237-246... 

Stein, J. L., Marsh, T. L., Wu, K. Y., Shizuya, H., and DeLong, E. F. (1996). Characterization of uncultivated prokaryotes Isolation and analysis of a 40-kilobase-pair genome fragment front a planktonic marine archaeon. /. Bacterial. 178, 591—599. 

Throughout the Archaean, prokaryotes, in the form of photosynthetic bacteria and cyanobacteria, were the main producers of organic carbon. The resting stages (cysts) of early unicellular eukaryotic organisms, probably representing planktonic algae and referred to as acritarchs, first appeared in the fossil record at c. 1.85 Ga and became abundant from c.l.OGa. 

Volkman, J.KT, Burger-Wiersma, T., Nichols, P.D., and Summons, R. E. (1988) Lipids and chemotaxonomy of Prochlorothrix hollandica, a planktonic prokaryote containing chlorophylls a and b. J. Phycol., 24, 554-559. 

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