The influence of the mode of nutrition on the digestive system of Ochromonas malhamensis.

摘要: The intracellular distribution and level of acid hydrolases in Ochromonas malhamensis were studied cells grown osmotrophically a defined medium, carbon-free starvation during phagotrophy each these media. By cytochemical techniques, little enzymic reaction product was observed the vacuoles osmotrophic medium. Starved cells, however, contained autophagic cannibalized other cells. Dense digestive Golgi cisternae starved Moreover, nutritionally complete medium ingested Escherichia coli which appeared containing product. Biochemical assays for lysosomal phosphatase (E.C. 3.1.3.2 orthophosphoric monoester phosphohydrolase) ribonuclease 2.7.7.16 ribonucleate nucleotido-2'-transferase) done on cultures same experimental treatments under identical assay conditions as study. During starvation, hydrolase specific activities consistently twice those found an fed E. showed no increase activity compared to controls not coli. latency fixed with glutaraldehyde reduced, suggesting that this fixative increases membrane permeability may release enzymes or their products into cytoplasmic matrix analysis. This could explain staining artifact sometimes glutaraldehyde-fixed when by Gomori technique. study confirms malhamensis, phytoflagellate, does produce can ingest bacteria, thereby fulfilling its role heterotroph aquatic food chain. When is phagocytosis causes appearance vacuoles, whereas total remains unchanged. An organic strongly stimulates hydrolaes appear whether occurs not.