Fig. 4.

Trypsin susceptibility of the canine nicotinamide adenine dinucleotide-cytochrome b5 reductase (b5R) soluble-forms. Wild-type (blue) and mutant (pink) b5Rs were treated with trypsin at 37°C for various periods. The assays were performed in triplicate. The residual activity was expressed as a percentage of the activity of the same enzyme before the trypsin treatment. The points are represented as the mean ± standard deviation. The significance of the differences was evaluated using Student’s t-test. *P<0.05, †P<0.01, and ‡P<0.005, compared with the values of wild-type b5R under the same treatments.