{{#invoke:Infobox|infobox}} Alpha-isocomene synthase (EC 4.2.3.136, MrTPS2) is an enzyme with system name (2E,6E)-farnesyl-diphosphate diphosphate-lyase (cyclizing, (-)-alpha-isocomene-forming).<ref>{{#invoke:Citation/CS1|citation |CitationClass=journal }}</ref> This enzyme catalyses the following chemical reaction

(2E,6E)-farnesyl diphosphate <math>\rightleftharpoons</math> (-)-alpha-isocomene + diphosphate

This enzyme is isolated from the roots of the plant Matricaria chamomilla var. recutita (chamomile).