title: Comparative functional characterization of eugenol synthase from four different Ocimum species: Implications on eugenol accumulation.
abstract: Isoprenoids and phenylpropanoids are the major secondary metabolite constituents in Ocimum genus. Though enzymes from phenylpropanoid pathway have been characterized from few plants, limited information exists on how they modulate levels of secondary metabolites. Here, we performed phenylpropanoid profiling in different tissues from five Ocimum species, which revealed significant variations in secondary metabolites including eugenol, eugenol methyl ether, estragole and methyl cinnamate levels. Expression analysis of eugenol synthase (EGS) gene showed higher transcript levels especially in young leaves and inflorescence; and were positively correlated with eugenol contents. Additionally, transcript levels of coniferyl alcohol acyl transferase, a key enzyme diverting pool of substrate to phenylpropanoids, were in accordance with their abundance in respective species. In particular, eugenol methyl transferase expression positively correlated with higher levels of eugenol methyl ether in Ocimum tenuiflorum. Further, EGSs were functionally characterized from four Ocimum species varying in their eugenol contents. Kinetic and expression analyses indicated, higher enzyme turnover and transcripts levels, in species accumulating more eugenol. Moreover, biochemical and bioinformatics studies demonstrated that coniferyl acetate was the preferred substrate over coumaryl acetate when used, individually or together, in the enzyme assay. Overall, this study revealed the preliminary evidence for varied accumulation of eugenol and its abundance over chavicol in these Ocimum species. Current findings could potentially provide novel insights for metabolic modulations in medicinal and aromatic plants.
authors: Plant Molecular Biology Unit, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India; Chemical Biology Unit, Division of Organic Chemistry, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India.
authors: Atul
authors: A
authors: Anand
authors: Plant Molecular Biology Unit, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India.
authors: Ramesha H
authors: RH
authors: Jayaramaiah
authors: Plant Molecular Biology Unit, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India; Chemical Biology Unit, Division of Organic Chemistry, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India; Department of Biotechnology, Savitribai Phule Pune University (Formerly University of Pune), Pune 411007, Maharashtra, India.
authors: Supriya D
authors: SD
authors: Beedkar
authors: Plant Molecular Biology Unit, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India; Chemical Biology Unit, Division of Organic Chemistry, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India.
authors: Priyanka A
authors: PA
authors: Singh
authors: Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University (Formerly University of Pune), Pune 411007, Maharashtra, India.
authors: Rakesh S
authors: RS
authors: Joshi
authors: Chemical Biology Unit, Division of Organic Chemistry, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India.
authors: Fayaj A
authors: FA
authors: Mulani
authors: Plant Molecular Biology Unit, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India.
authors: Bhushan B
authors: BB
authors: Dholakia
authors: Biospheres, Eshwari, 52/403, Laxminagar, Parvati, Pune 411 009, Maharashtra, India.
authors: Sachin A
authors: SA
authors: Punekar
authors: Department of Biotechnology, Savitribai Phule Pune University (Formerly University of Pune), Pune 411007, Maharashtra, India.
authors: Wasudeo N
authors: WN
authors: Gade
authors: Chemical Biology Unit, Division of Organic Chemistry, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India; CSIR-Institute of Genomics and Integrative Biology, Mall Road, New Delhi 110007, India. Electronic address: hv.thulasiram@ncl.res.in.
authors: Hirekodathakallu V
authors: HV
authors: Thulasiram
authors: Plant Molecular Biology Unit, Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India. Electronic address: ap.giri@ncl.res.in.
authors: Ashok P
authors: AP
authors: Giri
mesh_terms: D000498:Allyl Compounds / Q000302:isolation & purification / Q000378:metabolism; D000081248:Allylbenzene Derivatives; D000595:Amino Acid Sequence; D000840:Anisoles / Q000302:isolation & purification / Q000378:metabolism; D002934:Cinnamates / Q000302:isolation & purification / Q000378:metabolism; D017124:Conserved Sequence; D057075:Enzyme Assays; D005054:Eugenol / Q000031:analogs & derivatives / Q000302:isolation & purification / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D008780:Methyltransferases / Q000235:genetics / Q000378:metabolism; D062105:Molecular Docking Simulation; D056004:Molecular Dynamics Simulation; D031339:Ocimum / Q000201:enzymology* / Q000235:genetics; D044925:Oxidoreductases Acting on CH-CH Group Donors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010636:Phenols / Q000302:isolation & purification / Q000378:metabolism; D010802:Phylogeny; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics; D010938:Plant Oils / Q000737:chemistry; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D064210:Secondary Metabolism; D016415:Sequence Alignment; D013379:Substrate Specificity
chemical_list: C000605268:4-allylphenol; D000498:Allyl Compounds; D000081248:Allylbenzene Derivatives; D000840:Anisoles; D002934:Cinnamates; D010636:Phenols; D010938:Plant Oils; D011506:Proteins; D012333:RNA, Messenger; C005223:methyleugenol; D005054:Eugenol; C025385:methyl cinnamate; C007633:estragole; D044925:Oxidoreductases Acting on CH-CH Group Donors; C529970:eugenol synthase, Ocimum basilium; D008780:Methyltransferases; C106569:eugenol O-methyltransferase; C079238:alcohol O-acetyltransferase
keywords: Chavicol; Eugenol; Eugenol synthase; Ocimum; Phenylpropanoids; Secondary metabolites