Fig. 20

a Products of AgAS and its mutants. b Crystal structure of AgAS (PDB ID: 3S9V). c Class II active site of AgAS. The motif of class II terpene cyclase (D⁴⁰²XDD) are shown in sticks (white). The loop 482–492 is in red. d Class I active site of AgAS. The metal binding motifs of class I terpene cyclase: D⁶²¹DXXD, green; N⁷⁶⁵TE, magenta