3.3.2.15 D38A inactive variant 654709 3.3.2.15 K122A lower activity than mutant enzyme 654709 3.3.2.15 additional information loss of PhzD in the phenazine biosynthetic operon expressed in Escherichia coli does not result in the loss of phenazine production. Escherichia coli pyridoxamine oxidases may complement phzD function 738259