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β-Selinene cyclase (EC 4.2.3.66) is an enzyme with systematic name(2E,6E)-farnesyl-diphosphate diphosphate-lyase (β-selinene-forming). This enzyme catalyses the following chemical reaction
Initial cyclization gives (+)-germacrene A in an enzyme-bound form.
References
Belingheri L, Cartayrade A, Pauly G, Gleizes M (January 1992). "Partial purification and properties of the sesquiterpene β-selinene cyclase from Citrofortunella mitis". Plant Science. 84: 129–136. doi:10.1016/0168-9452(92)90126-7.