title: Acid hydrolase activity during growth and encystment in Acanthamoeba castellanii.
abstract: The activity and sedimentation of acid phosphatase (APase), acid deoxyribonuclease (DNase), and acid ribonuclease (RNase) were investigated throughout growth and encystment in Acanthamoeba castellanii. The activities/mg protein of all 3 hydrolases are high in young cultures and decrease to constant levels in postlog cells. The RNase activity/ameba decreases 50% during growth, whereas the activity/cell of both APase and DNase remains constant. The percent sedimentation at 20,000 g of all 3 enzymes gradually increases from about 40% in midlog to a plateau of 80% in postlog cells. During encystment, the sedimentation behavior of RNase differs from that of APase and DNase. Encystment is characterized by a differential decrease in the activity/cell of the 3 hydrolases, with RNase decreasing most rapidly and APase least rapidly. APase is unique in that a transient increase of its specific activity is noted during encystment, even though its activity/cell is decreasing.
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000656:Amoeba / Q000201:enzymology / Q000254:growth & development*; D000818:Animals; D003851:Deoxyribonucleases / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D012260:Ribonucleases / Q000378:metabolism
chemical_list: D003851:Deoxyribonucleases; D012260:Ribonucleases; D000135:Acid Phosphatase; D010744:Phosphoric Monoester Hydrolases