title: Functional characterization and transient expression manipulation of a new sesquiterpene synthase involved in β-caryophyllene accumulation in Ocimum.
abstract: The genus Ocimum has a unique blend of diverse secondary metabolites, with major proportion of terpenoids including mono- and sesquiterpenes. Although, β-Caryophyllene, bicyclic sesquiterpene, is one of the major terpene found in Ocimum species and known to possess several biological activities, not much is known about its biosynthesis in Ocimum. Here, we describe isolation and characterization of β-caryophyllene synthase gene from Ocimum kilimandscharicum Gürke (OkBCS- GenBank accession no. KP226502). The open reading frame of 1629 bp encoded a protein of 542 amino acids with molecular mass of 63.6 kDa and pI value of 5.66. The deduced amino acid sequence revealed 50-70% similarity with known sesquiterpene synthases from angiosperms. Recombinant OkBCS converted farnesyl diphosphate to β-caryophyllene as a major product (94%) and 6% α-humulene. Expression variation of OkBCS well corroborated with β-caryophyllene levels in different tissues from five Ocimum species. OkBCS transcript revealed higher expression in leaves and flowers. Further, agro-infiltration based transient expression manipulation with OkBCS over-expression and silencing confirmed its role in β-caryophyllene biosynthesis. These findings may potentially be further utilized to improve plant defense against insect pests.
authors.affiliation: Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India.
authors.forename: Ramesha H
authors.initials: RH
authors.lastname: Jayaramaiah
authors.affiliation: Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India; Division of Organic Chemistry, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India.
authors.forename: Atul
authors.initials: A
authors.lastname: Anand
authors.affiliation: Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India; Department of Biotechnology, Savitribai Phule Pune University, Pune 411007, Maharashtra, India.
authors.forename: Supriya D
authors.initials: SD
authors.lastname: Beedkar
authors.affiliation: Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India.
authors.forename: Bhushan B
authors.initials: BB
authors.lastname: Dholakia
authors.affiliation: Biospheres, Eshwari, 52/403, Lakshminagar, Parvati, Pune 411 009, Maharashtra, India.
authors.forename: Sachin A
authors.initials: SA
authors.lastname: Punekar
authors.affiliation: Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India.
authors.forename: Raviraj M
authors.initials: RM
authors.lastname: Kalunke
authors.affiliation: Department of Biotechnology, Savitribai Phule Pune University, Pune 411007, Maharashtra, India.
authors.forename: Wasudeo N
authors.initials: WN
authors.lastname: Gade
authors.affiliation: 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.forename: Hirekodathakallu V
authors.initials: HV
authors.lastname: Thulasiram
authors.affiliation: Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, Maharashtra, India. Electronic address: ap.giri@ncl.res.in.
authors.forename: Ashok P
authors.initials: AP
authors.lastname: Giri
mesh_terms: D060054:Agrobacterium / Q000378:metabolism; D019883:Alkyl and Aryl Transferases / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D008401:Gas Chromatography-Mass Spectrometry; D005786:Gene Expression Regulation; D020868:Gene Silencing; D019684:Magnoliopsida / Q000378:metabolism; D008969:Molecular Sequence Data; D000081222:Monocyclic Sesquiterpenes; D031339:Ocimum / Q000201:enzymology* / Q000235:genetics; D016366:Open Reading Frames; D010802:Phylogeny; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D000081223:Polycyclic Sesquiterpenes; D011106:Polyisoprenyl Phosphates / Q000737:chemistry; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D012717:Sesquiterpenes / Q000737:chemistry*
chemical_list: D000081222:Monocyclic Sesquiterpenes; D010940:Plant Proteins; D000081223:Polycyclic Sesquiterpenes; D011106:Polyisoprenyl Phosphates; D011994:Recombinant Proteins; D012717:Sesquiterpenes; C042686:humulene; C004808:farnesyl pyrophosphate; C024714:caryophyllene; D019883:Alkyl and Aryl Transferases
keywords: Natural product biosynthesis; Ocimum; Terpene synthase; Transient expression; β-Caryophyllene