Fig. 5.From: Structural and mechanistic basis of the high catalytic activity of monooxygenase Tet(X4) on tigecyclineSuperimposition of the Tet(X4) structure (cartoon of Tet(X4) shown in blue) and Tet(X2) structure (cartoon of Tet(X2) shown in gray). FAD in Tet(X4) is shown in orange, FAD in Tet(X2) is shown in yellow; the red dashed box indicates the structural difference between the substrate-binding domain of Tet(X4) and Tet(X2), with details shown in the enlarged dashed box; key residues of Tet(X4) that are different from Tet(X2) are depicted as sticksBack to article page