PURIFICATION AND SOME PROPERTIES OF ELASTASE FROM HEPATOPANCREAS OF KING CRAB PARALITHODES-CAMTSCHATICA

1. Elastase has been purified from the hepatopancreas of the king crab (Paralithodes camtschatica). Specific activity of the enzyme measured toward Suc-(Ala)3-pNA and Boc-(Ala)3-pNA was 926 and 3700 mUnits per mg of protein, respectively. 2. The enzyme is an anion protein (pl 4.5 ) with an approximate mol.wt of 28.5 kDa 3. The enzyme exhibited a bel l-shaped pH-dependence for the hydrolysis of Suc-(Ala)3-pNA with a max imum at 8-8.5. Under these conditions the values of K(m) and k(cat) of the crab elastase are 4 mM and 4.75 s-1, respectively. 4. The serine elastase is effectively inhibited by elastinal and diisopropylfluoroph osphate. 5. It is shown that some salts except HgCl2 activate the prot ease. In the presence of HgCl2 with concentrations of 10 mM and higher , the crab elastase is inactive. SDS and Triton X-100 have no any effe ct on the activity of crab elastase.