:(+)-car-3-ene synthase

{{Short description|Class of enzymes}}

{{Infobox enzyme

| Name = (+)-car-3-ene synthase

| EC_number = 4.2.3.107

| CAS_number =

| GO_code =

| image =

| width =

| caption =

}}

(+)-Car-3-ene synthase (EC 4.2.3.107, 3-carene cyclase, 3-carene synthase, 3CAR, (+)-3-carene synthase) is an enzyme with systematic name geranyl-diphosphate diphosphate-lyase [cyclizing, (+)-car-3-ene-forming].{{cite journal | vauthors = Savage TJ, Croteau R | title = Biosynthesis of monoterpenes: regio- and stereochemistry of (+)-3-carene biosynthesis | journal = Archives of Biochemistry and Biophysics | volume = 305 | issue = 2 | pages = 581–7 | date = September 1993 | pmid = 8373196 | doi = 10.1006/abbi.1993.1464 }}{{cite journal | vauthors = Savage TJ, Ichii H, Hume SD, Little DB, Croteau R | title = Monoterpene synthases from gymnosperms and angiosperms: stereospecificity and inactivation by cysteinyl- and arginyl-directed modifying reagents | journal = Archives of Biochemistry and Biophysics | volume = 320 | issue = 2 | pages = 257–65 | date = July 1995 | pmid = 7625832 | doi = 10.1016/0003-9861(95)90008-x }}{{cite journal | vauthors = Savage TJ, Hatch MW, Croteau R | title = Monoterpene synthases of Pinus contorta and related conifers. A new class of terpenoid cyclase | journal = The Journal of Biological Chemistry | volume = 269 | issue = 6 | pages = 4012–20 | date = February 1994 | doi = 10.1016/S0021-9258(17)41735-2 | pmid = 8307957 | doi-access = free }}{{cite journal | vauthors = Fäldt J, Martin D, Miller B, Rawat S, Bohlmann J | title = Traumatic resin defense in Norway spruce (Picea abies): methyl jasmonate-induced terpene synthase gene expression, and cDNA cloning and functional characterization of (+)-3-carene synthase | journal = Plant Molecular Biology | volume = 51 | issue = 1 | pages = 119–33 | date = January 2003 | pmid = 12602896 | doi = 10.1023/A:1020714403780 | s2cid = 21153303 }}{{cite journal | vauthors = Hamberger B, Hall D, Yuen M, Oddy C, Hamberger B, Keeling CI, Ritland C, Ritland K, Bohlmann J | title = Targeted isolation, sequence assembly and characterization of two white spruce (Picea glauca) BAC clones for terpenoid synthase and cytochrome P450 genes involved in conifer defence reveal insights into a conifer genome | journal = BMC Plant Biology | volume = 9 | pages = 106 | date = August 2009 | pmid = 19656416 | pmc = 2729077 | doi = 10.1186/1471-2229-9-106 | doi-access = free }}{{cite journal | vauthors = Hall DE, Robert JA, Keeling CI, Domanski D, Quesada AL, Jancsik S, Kuzyk MA, Hamberger B, Borchers CH, Bohlmann J | title = An integrated genomic, proteomic and biochemical analysis of (+)-3-carene biosynthesis in Sitka spruce (Picea sitchensis) genotypes that are resistant or susceptible to white pine weevil | journal = The Plant Journal | volume = 65 | issue = 6 | pages = 936–48 | date = March 2011 | pmid = 21323772 | doi = 10.1111/j.1365-313x.2010.04478.x }} This enzyme catalyses the following chemical reaction

: geranyl diphosphate $\backslash rightleftharpoons$ (+)-car-3-ene + diphosphate

The enzyme reacts with (3S)-{{not a typo|linalyl}} diphosphate twice as rapidly as geranyl diphosphate.