Carbon utilization by the omnivorous flagellate Paraphysomonas imperforata

Heterotrophic Nanoflagellate, Paraphysomonas imperforata

Two different psychrophilic types of the heterotrophic nanoflagellate Paraphysomonas imperforata were isolated from Newfoundland coastal waters and the Arctic Ocean. When fed bacteria without food limitation, both isolates were able to grow at temperatures from -1.8 to 20°C, with maximum growth rates of 3.28 day-' at 15°C and 2.28 day-l at 12.3°C for the Newfoundland and the Arctic isolates, re...

The ecology of Paraphysomonas imperforata based on studies employing oligonucleotide probe identification in coastal water samples and enrichment cultures

The geographical distribution and seasonal abundance of the cosmopolitan heterotrophic flagellate Paraphysomonas imperforata in several coastal waters was examined using species-specific oligonucleotide hybridization probes which target small subunit ribosomal RNA. P. imperforata was found to occur in several coastal environments, but at very low abundances (typically ,50 cells ml21). The seaso...

Protistan grazing analysis by flow cytometry using prey labeled by in vivo expression of fluorescent proteins.

Selective grazing by protists can profoundly influence bacterial community structure, and yet direct, quantitative observation of grazing selectivity has been difficult to achieve. In this investigation, flow cytometry was used to study grazing by the marine heterotrophic flagellate Paraphysomonas imperforata on live bacterial cells genetically modified to express the fluorescent protein marker...

Regeneration of phosphorus and nitrogen by four species of heterotrophic nanoflagellates feeding on three nutritional States of a single bacterial strain.

Three physiological states of a single bacterial strain, namely, balanced, phosphorus-rich, and nitrogen-rich bacteria, were obtained by culturing a bacterial strain in chemostats under three different nutrient regimens. Each was shown to be distinctly different in elemental composition with respect to C/N/P ratio. These bacteria were fed to four species of heterotrophic nanoflagellates in batc...

A Case of Hymen Imperforata