caa a22 4500 465790275 CHVBK 20180323112022.0 cr unu---uuuuu 170327e19900101xx s 000 0 eng 10.1007/BF02015056 doi (NATIONALLICENCE)springer-10.1007/BF02015056 Relationship between phototrophy and phagotrophy in the mixotrophic chrysophyte Poterioochromonas malhamensis [Elektronische Daten] [Robert Sanders, Karen Porter, David Caron] The time scales involved in the transition between phototrophic and phagotrophic modes of nutrition were examined in the mixotrophic chrysophytePoterioochromonas malhamensis. Phagotrophy began almost immediately when bacteria were added to phototrophically growing cultures of the alga, and chlorophylla concentration per cell in these cultures decreased over a 24-hour period. Chlorophyll concentrations per cell began to increase when bacteria were grazed to a density of approximately 106 ml−1, but after more than 24 hours they had not returned to the higher chlorophyll concentrations observed in the phototrophically grown cultures. Bacterivory was the dominant mode of nutrition in all cultures containing heat-killed bacteria. Photosynthesis did not contribute more than ≈7% of the total carbon budget of the alga when in the presence of abundant heat-killed bacteria. Bacterial density was the primary factor influencing the ability ofP. malhamensis to feed phagotrophically, while light intensity, pH, and the presence of dissolved organic matter had no effect on phagotrophy. We conclude thatP. malhamensis is capable of phagotrophy at all times. In contrast, phototrophy is inducible in the light during starvation and is a long-term survival strategy for this mixotrophic alga (i.e., it operates on time scales greater than a diel cycle). Springer-Verlag New York Inc., 1990 Sanders Robert Division of Environmental Research, Philadelphia Academy of Natural Sciences, 19th and the Parkway, 19103, Philadelphia, Pennsylvania aut Porter Karen Zoology Department, University of Georgia, 30602, Athens, Georgia aut Caron David Biology Department, Woods Hole Oceanographic Institution, 02543, Woods Hole, Massachusetts, USA aut Microbial Ecology Springer-Verlag 19/1(1990-01-01), 97-109 0095-3628 19:1<97 1990 19 248 https://doi.org/10.1007/BF02015056 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02015056 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sanders Robert Division of Environmental Research, Philadelphia Academy of Natural Sciences, 19th and the Parkway, 19103, Philadelphia, Pennsylvania aut NATIONALLICENCE 700 1- Porter Karen Zoology Department, University of Georgia, 30602, Athens, Georgia aut NATIONALLICENCE 700 1- Caron David Biology Department, Woods Hole Oceanographic Institution, 02543, Woods Hole, Massachusetts, USA aut NATIONALLICENCE 773 0- Microbial Ecology Springer-Verlag 19/1(1990-01-01), 97-109 0095-3628 19:1<97 1990 19 248 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer