Heat stability and trypsin susceptibility of the wild-type and mutant b5R.

b5R was diluted to 2 μg/μL with 50 mmol/L Tris-HCl (pH 8.0) containing 1 mmol/L EDTA and 0.1 mmol/L DTT. □, wild type; ▵, mutant. (A) Samples were incubated for 10 minutes at various temperatures. (B) Incubation at 37°C for various times. (C) Incubation for various times at 37°C with 1.5 U/μL trypsin.