BIO011 Kinetic Characterization of a (Na+,K+)-ATPase Activity in the Freshwater Shrimp Zoeae I Macrobrachium rosenbergii

Resumo

Macrobrachium rosenbergii is the species of freshwater shrimp more used in the commercial aquaculture. This freshwater prawn, also known as the giant Malaysian prawn, is native to the tropical Indo-Pacific region and has been introduced in several countries due to its economic interest. M. rosenbergii belongs to the family Palaemonidae which include the brackish and freshwater shrimps, where most species which comprise this family require brackish water to complete the early stages of their life cycle. The newly hatched larvae must reach brackish water with salinities of 10 to 14 parts per thousand (ppt) within two days or they will not survive. At this stage, they feed on zooplankton, worms and the larvae of other aquatic organisms and to reach the post-larval stage, the larvae undergo about 11 molts in approximately 35 days. During larval development many changes occur both in structure and physiology of the shrimp. The ability to survive in different salinities, until its complete establishment in freshwater, is dependent on enzymes that control and regulate the metabolism of the animal. Various enzymes are responsible for active ion transport in crustacean although their importance in osmoregulatory mechanisms differs among species. The (Na+,K+)-ATPase and the V(H+)-ATPase are the two most important enzymes.