Influence Of Alpha2 Macroglobulin Of Rabbit On Enzyme Activity Of Trypsin And Chymotrypsin

1. 1. The rabbit α 2 macroglobulin ( α 2 M) can bind trypsin and chymotrypsin with the formation of an enzymatically active complex. The links are strong enough to resist gel filtration. 2. 2. The effect of α 2 M on the esterolytic activities of trypsin and chymotrypsin was investigated using benzoyl-arginine ethyl-ester, p- tosyl- l -arginine methyl ester and acetyl-tyrosine ethyl ester as substrates. 3. 3. Michaelis constants of the complexes were determined by the method of Eadie (1942). The proteolytic activity was investigated using caseine as a substrate. 4. 4. The competition of trypsin and chymotrypsin for the association site was studied and the ability of the α 2 M to protect these enzymes from soybean trypsin inhibitor was determined. 5. 5. One mole of α 2 M binds 2 moles of trypsin or chymotrypsin. 6. 6. Rabbit α 2 M has numerous similarities with rabbit α 1 M.