@article {Gang:2002p8027,
	title = {Characterization of phenylpropene O-methyltransferases from sweet basil: facile change of substrate specificity and convergent evolution within a plant O-methyltransferase family},
	journal = {Plant Cell},
	volume = {14},
	number = {2},
	year = {2002},
	month = {Feb},
	pages = {505{\textendash}19},
	abstract = {Some basil varieties are able to convert the phenylpropenes chavicol and eugenol to methylchavicol and methyleugenol, respectively. Chavicol O-methyltransferase (CVOMT) and eugenol O-methyltransferase (EOMT) cDNAs were isolated from the sweet basil variety EMX-1 using a biochemical genomics approach. These cDNAs encode proteins that are 90\% identical to each other and very similar to several isoflavone O-methyltransferases such as IOMT, which catalyzes the 4{\textquoteright}-O-methylation of 2,7,4{\textquoteright}-trihydroxyisoflavanone. On the other hand, CVOMT1 and EOMT1 are related only distantly to (iso)eugenol OMT from Clarkia breweri, indicating that the eugenol O-methylating enzymes in basil and C. breweri evolved independently. Transcripts for CVOMT1 and EOMT1 were highly expressed in the peltate glandular trichomes on the surface of the young basil leaves. The CVOMT1 and EOMT1 cDNAs were expressed in Escherichia coli, and active proteins were produced. CVOMT1 catalyzed the O-methylation of chavicol, and EOMT1 also catalyzed the O-methylation of chavicol with equal efficiency to that of CVOMT1, but it was much more efficient in O-methylating eugenol. Molecular modeling, based on the crystal structure of IOMT, suggested that a single amino acid difference was responsible for the difference in substrate discrimination between CVOMT1 and EOMT1. This prediction was confirmed by site-directed mutagenesis, in which the appropriate mutants of CVOMT1 (F260S) and EOMT1 (S261F) were produced that exhibited the opposite substrate preference relative to the respective native enzyme.},
	keywords = {Amino Acid Sequence, Anisoles, DNA: Complementary, Escherichia coli, Eugenol, Evolution: Molecular, Gene Expression, Gene Expression Regulation: Enzymologic, Gene Expression Regulation: Plant, Isoflavones, Methyltransferases, Molecular Sequence Data, Molecular Structure, Mutagenesis: Site-Directed, Mutation, Ocimum basilicum, Phylogeny, Recombinant Proteins, Sequence Homology: Amino Acid, Substrate Specificity},
	author = {David R Gang and Noa Lavid and Chloe Zubieta and Feng Chen and Till Beuerle and Efraim Lewinsohn and Joseph P Noel and Eran Pichersky}
}
@article {Iijima:2004p8022,
	title = {The biochemical and molecular basis for the divergent patterns in the biosynthesis of terpenes and phenylpropenes in the peltate glands of three cultivars of basil},
	journal = {Plant Physiol},
	volume = {136},
	number = {3},
	year = {2004},
	month = {Nov},
	pages = {3724{\textendash}36},
	abstract = {Surface glandular trichomes distributed throughout the aerial parts of sweet basil (Ocimum basilicum) produce and store monoterpene, sesquiterpene, and phenylpropene volatiles. Three distinct basil chemotypes were used to examine the molecular mechanisms underlying the divergence in their monoterpene and sesquiterpene content. The relative levels of specific terpenes in the glandular trichomes of each cultivar were correlated with the levels of transcripts for eight genes encoding distinct terpene synthases. In a cultivar that produces mostly (R)-linalool, transcripts of (R)-linalool synthase (LIS) were the most abundant of these eight. In a cultivar that synthesizes mostly geraniol, transcripts of geraniol synthase were the most abundant, but the glands of this cultivar also contained a transcript of an (R)-LIS gene with a 1-base insertion that caused a frameshift mutation. A geraniol synthase-LIS hybrid gene was constructed and expressed in Escherichia coli, and the protein catalyzed the formation of both geraniol and (R)-linalool from geranyl diphosphate. The total amounts of terpenes were correlated with total levels of terpene synthase activities, and negatively correlated with levels of phenylpropanoids and phenylalanine ammonia lyase activity. The relative levels of geranyl diphosphate synthase and farnesyl diphosphate synthase activities did not correlate with the total amount of terpenes produced, but showed some correlation with the ratio of monoterpenes to sesquiterpenes.},
	keywords = {Amino Acid Sequence, Gene Expression Regulation: Plant, Genetic Variation, Molecular Sequence Data, Molecular Structure, Ocimum basilicum, Phylogeny, Sequence Homology: Amino Acid, Styrenes, Terpenes},
	doi = {10.1104/pp.104.051318},
	author = {Yoko Iijima and Rachel Davidovich-Rikanati and Eyal Fridman and David R Gang and Einat Bar and Efraim Lewinsohn and Eran Pichersky}
}
@article {Paton:2004p8018,
	title = {Phylogeny and evolution of basils and allies (Ocimeae, Labiatae) based on three plastid DNA regions},
	journal = {Molecular Phylogenetics and Evolution},
	volume = {31},
	number = {1},
	year = {2004},
	month = {Apr},
	pages = {277{\textendash}99},
	abstract = {A phylogeny of basils and allies (Lamiaceae, tribe Ocimeae) based on sequences of the trnL intron, trnL-trnF intergene spacer and rps 16 intron of the plastid genome is presented. Several methods were used to reconstruct phylogenies and to assess statistical support for clades: maximum parsimony with equally and successively weighted characters, bootstrap resampling, and Bayesian inference. The phylogeny is used to investigate the distribution of morphological, pericarp anatomy, chemical, and pollen characters as well as the geographical distribution of the clades. Tribe Ocimeae is monophyletic and easily diagnosable with morphological synapomorphies. There are monophyletic clades within Ocimeae that broadly correspond to currently recognised subtribes: Lavandulinae, Hyptidinae, Ociminae, and Plectranthinae. Only Lavandulinae has clear non-molecular synapomorphies. Several currently recognised genera are not monophyletic. Floral morphology consistent with sternotribic pollination is most common in Ocimeae, but there are independent departures from this model. Buzz pollination is likely in some species, the only postulated occurrence of this within Lamiaceae. Quinone diterpenoids and flavones in the leaf exudates differ in their distributions across the phylogeny and this could contribute to differences in the recorded medicinal as well as pesticidal uses of the species in the different clades. Mapping geographic distribution on to an ultrametric phylogenetic tree produced using non-parametric rate smoothing supports an Asiatic origin for Ocimeae. There are several secondary occurrences in Asia arising from the African Ociminae and Plectranthinae clades. Colonisation of Madagascar occurred at least five times, and New World colonisation occurred at least three times.},
	keywords = {Bayes Theorem, Biological Evolution, Diterpenes, DNA: Intergenic, Flavonoids, Introns, Lamiaceae, Molecular Sequence Data, Ocimum basilicum, Phylogeny, Plastids, Pollen},
	doi = {10.1016/j.ympev.2003.08.002},
	author = {Alan J Paton and David Springate and Somran Suddee and Donald Otieno and Ren{\'e}e J Grayer and Madeline M Harley and Fiona Willis and Monique S J Simmonds and Martyn P Powell and Vincent Savolainen}
}
@article {Kapteyn:2007p7982,
	title = {Evolution of Cinnamate/p-coumarate carboxyl methyltransferases and their role in the biosynthesis of methylcinnamate},
	journal = {Plant Cell},
	volume = {19},
	number = {10},
	year = {2007},
	month = {Oct},
	pages = {3212{\textendash}29},
	abstract = {Methylcinnamate, which is widely distributed throughout the plant kingdom, is a significant component of many floral scents and an important signaling molecule between plants and insects. Comparison of an EST database obtained from the glandular trichomes of a basil (Ocimum basilicum) variety that produces high levels of methylcinnamate (line MC) with other varieties producing little or no methylcinnamate identified several very closely related genes belonging to the SABATH family of carboxyl methyltransferases that are highly and almost exclusively expressed in line MC. Biochemical characterization of the corresponding recombinant proteins showed that cinnamate and p-coumarate are their best substrates for methylation, thus designating these enzymes as cinnamate/p-coumarate carboxyl methyltransferases (CCMTs). Gene expression, enzyme activity, protein profiling, and metabolite content analyses demonstrated that CCMTs are responsible for the formation of methylcinnamate in sweet basil. A phylogenetic analysis of the entire SABATH family placed these CCMTs into a clade that includes indole-3-acetic acid carboxyl methyltransferases and a large number of uncharacterized carboxyl methyltransferase-like proteins from monocots and lower plants. Structural modeling and ligand docking suggested active site residues that appear to contribute to the substrate preference of CCMTs relative to other members of the SABATH family. Site-directed mutagenesis of specific residues confirmed these findings.},
	keywords = {Amino Acid Sequence, Blotting: Southern, Cinnamates, Evolution: Molecular, Expressed Sequence Tags, Gas Chromatography-Mass Spectrometry, Gene Expression Profiling, Kinetics, Methylation, Methyltransferases, Models: Molecular, Molecular Sequence Data, Molecular Structure, Ocimum basilicum, Phylogeny, Plant Proteins, Protein Isoforms, Proteomics, Reverse Transcriptase Polymerase Chain Reaction, Sequence Homology: Amino Acid, Substrate Specificity},
	doi = {10.1105/tpc.107.054155},
	author = {Jeremy Kapteyn and Anthony V Qualley and Zhengzhi Xie and Eyal Fridman and Natalia Dudareva and David R Gang}
}
@article {Iijima:2004p8034,
	title = {Characterization of geraniol synthase from the peltate glands of sweet basil},
	journal = {Plant Physiol},
	volume = {134},
	number = {1},
	year = {2004},
	month = {Jan},
	pages = {370{\textendash}9},
	abstract = {The monoterpene fraction of the lemon-scented sweet basil (Ocimum basilicum) cv Sweet Dani consists mostly of citral (a mixture of geranial and neral), with lower levels of geraniol and nerol. These compounds are stored in the peltate glands found on the leaf epidermis. Younger leaves, which have a higher density of such glands, also have a higher content of monoterpenes than older leaves. Geraniol synthase (GES) activity, generating geraniol from geranyl diphosphate, was shown to be localized exclusively or almost exclusively to glands. GES activity resides in a homodimeric protein that was purified to near homogeneity. Basil GES requires Mn2+ as a divalent metal cofactor for activity and produces only geraniol from geranyl diphosphate. Km values of 21 and 51 microM were obtained for geranyl diphosphate and Mn2+, respectively. In the presence of 18O-labeled water, GES catalyzed the formation of 18O-geraniol from geranyl diphosphate, indicating that the reaction mechanism of GES is similar to that of other monoterpene synthases and is different from the action of phosphatases. A GES cDNA was isolated based on analysis of a glandular trichome expressed sequence tag database, and the sequence of the protein encoded by this cDNA shows some similarity to sequences of other terpene synthases. The expression of the GES cDNA in Escherichia coli resulted in a protein with enzymatic activity essentially identical to that of plant-purified GES. RNA gel-blot analysis indicated that GES is expressed in glands but not in leaves of basil cv Sweet Dani, whose glands contain geraniol and citral, and not in glands or leaves of another basil variety that makes other monoterpenes but not geraniol or citral.},
	keywords = {Alkyl and Aryl Transferases, Amino Acid Sequence, DNA: Complementary, DNA: Plant, Gene Expression, Genes: Plant, Molecular Sequence Data, Ocimum basilicum, Phylogeny, Plant Structures, Sequence Homology: Amino Acid, Terpenes},
	doi = {10.1104/pp.103.032946},
	author = {Yoko Iijima and David R Gang and Eyal Fridman and Efraim Lewinsohn and Eran Pichersky}
}
