Aspartic proteinases in the digestive tract of marine decapod crustaceans

Aspartic proteinases in the digestive tract of marine decapod crustaceans.

Decapod crustaceans synthesize highly active proteolytic enzymes in the midgut gland and release at least a part of them into the stomach where they facilitate the first step in peptide hydrolysis. The most common proteinases in the gastric fluid characterized so far are serine proteinases, that is, trypsin and chymotrypsin. These enzymes show highest activities at neutral or slightly alkaline ...

The Decapod Crustaceans of Iowa

Cephalopods and Decapod Crustaceans

Patterns of Water and Solute Regulation in the Muscle Fibres of Osmo- Conforming Marine Decapod Crustaceans

1. The patterns of myoplasmic water and solute regulation were examined in several species of marine decapod crustaceans acclimated to various salinities. Three osmoconformers (Callianassa cahformemsis, Cancer antennarius, Emerita analoga) and one weak osmoregulator {Pachygrapsus crassipes) were studied. 2. Although haemolymph water and solute activities varied with adaptational salinity in the...

Extracellular acid–base balance in decapod crustaceans

influence extracellular acid–base status in brachyuran decapod crustaceans (Truchot, 1973; Truchot, 1981; Truchot, 1992; Mangum et al., 1976; Henry and Cameron, 1982; Wheatly, 1985). Although the underlying mechanisms and the physiological consequences remain unclear, the basis for the relationship between acid–base status and ion regulation can be attributed to the catalysed hydration of CO2 b...