Studies on cell deformability. II. Effects of some proteolytic enzymes.

Murine sarcoma 37 ascites cells were treated with the proteolytic enzymes, trypsin and chymotrypsin, after which cellular deformability and electrophoretic mobility were measured. It was shown that incubation with trypsin increased the ease with which the cells could be deformed without changing electrophoretic mobility, and that diisopropylfluorophosphate (DFP)-trypsin was inactive, a fact which suggests that trypsin-sensitive peptide linkages help to maintain the "tension" at the cell periphery. On the other hand, chymotrypsin reduced cellular electrophoretic mobility without appreciably altering deformability. This suggests that, although chymotrypsin-sensitive bonds do not contribute to "tension," they are in some way associated with charged groups at the cell periphery.