Chrysanthemyl diphosphate synthase

Chrysanthemic acid (1) consists of ten carbons, suggesting that it is a monoterpene. The cyclopropane ring of the acid moiety is a feature of pyrethrins. Rivera et al. isolated chrysanthemyl pyrophosphate synthase (CPPase or alternatively referred to as chrysanthemyl diphosphate synthase) underlying the formation of chrysanthemyl pyrophosphate (16) containing a cyclopropane ring from two molecules of dimethylallyl pyrophosphate (15) (DMAPP) and the gene thereof [21]. They found that the reaction involves the cF-2-3 cyclopropanation of DMAPPs in a non-head-to-tail manner. 

Rivera SB, Swedlund BD, King GJ et al (2001) Chrysanthemyl diphosphate synthase isolation of the gene and characterization of the recombinant non-head-to-tail monoterpene synthase from Chrysanthemum cinerariaefolium. Proc Natl Acad Sci USA 98 4373 -378... 

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