and the activity of T220S/I31L mutantwas close to the wild-type NK. On the other hand, the M222A/I31L mutant still showed a significant decrease in catalytic efficiency relative to the wild-type NK
and theactivity of T220S/I31L mutantwas close to the wild-type NK. On theother hand, the M222A/I31L mutant still showed a significantdecrease in catalytic efficiency relative to the wild-type NK