title: The unmasking of proteolytic activity during the early development of Artemia salina. Identification of a precursor after hatching.
abstract: The proteolytic activities of Artemia salina immediately after hatching are found masked in a precursor of high molecular weight (approximately 100000). The molecular weight of this precursor decreases slightly as development proceeds. However, its kinetic and chromatographic properties vary greatly. Shortly after hatching, the activities are highly inhibited, can be activated severalfold by the chaotropic agent potassium iodide and are not proportional to the amount of enzyme-containing extract added. Later after hatching, its kinetics become normal. From these observations we have concluded that (a) the majority, if not all, of the proteinase activities found later in development are already present immediately after hatching, although in an inhibited state that is gradually activated; (b) the proteinases are not found free in the cytoplasm but in a complex which may allow regulation of their activity.
mesh_terms: D000818:Animals; D001156:Artemia / Q000201:enzymology* / Q000254:growth & development; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D010450:Endopeptidases / Q000378:metabolism*; D004792:Enzyme Precursors / Q000378:metabolism*; D005450:Fluorescamine; D007700:Kinetics; D007814:Larva / Q000201:enzymology; D008970:Molecular Weight
chemical_list: D004792:Enzyme Precursors; D005450:Fluorescamine; D010450:Endopeptidases