Title: | Enzymatic production and emission of floral scent volatiles in Jasminum sambac |
Author(s): | Bera P; Mukherjee C; Mitra A; |
Address: | "Natural Product Biotechnology Group, Agricultural and Food Engineering Department, Indian Institute of Technology Kharagpur, Kharagpur 721 302, India. Natural Product Biotechnology Group, Agricultural and Food Engineering Department, Indian Institute of Technology Kharagpur, Kharagpur 721 302, India. Electronic address: adin@iitkgp.ac.in" |
DOI: | 10.1016/j.plantsci.2016.11.013 |
ISSN/ISBN: | 1873-2259 (Electronic) 0168-9452 (Linking) |
Abstract: | "Floral scent composed of low molecular weight volatile organic compounds. The sweet fragrance of any evening blooming flower is dominated by benzenoid and terpenoid volatile compounds. Floral scent of Jasminum sambac (Oleaceae) includes three major benzenoid esters - benzylacetate, methylbenzoate, and methylsalicylate and three major terpene compounds viz. (E)-beta-ocimene, linalool and alpha-farnesene. We analyzed concentrations and emission rates of benzenoids and terpenoids during the developmental stages of J. sambac flower. In addition to spatial emission from different floral parts, we studied the time-course mRNA accumulations of phenylalanine ammonia-lyase (PAL) and the two representative genes of terpenoid pathway, namely 1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR) and terpene synthase (TPS). Further, in vitro activities of several enzymes of phenylpropanoid/benzenoid pathway viz., PAL and acetyl-coenzyme A: benzylalcohol acetyltransferase (BEAT), S-adenosyl-l-methionine: benzoic acid carboxyl methyl transferase (BAMT) and S-adenosyl-l-methionine: salicylic acid carboxyl methyltransferase (SAMT) were studied. All the above enzyme activities along with the in vitro activities of DXR and TPS were found to follow a certain rhythm as observed in the emission of different benzenoid and terpenoid compounds. Linalool emission peaked after petal opening and coincided with maximal expression of JsTPS gene as evidenced from RT-PCR analyses (semi-quantitative). The maximum transcript accumulation of this gene was observed in flower petals, indicating that the petals of J. sambac flower play an important role as a major contributor of volatile precursors. The transcripts accumulation of JsDXR and JsTPS in different developmental stages and in different floral part showed that emissions of terpenoid volatiles in J. sambac flower are partially regulated at transcription levels" |
Keywords: | Aldose-Ketose Isomerases/genetics/metabolism Alkyl and Aryl Transferases/genetics/metabolism Flowers/enzymology/*metabolism Jasminum/enzymology/genetics/*metabolism Methyltransferases/metabolism *Odorants Phenylalanine Ammonia-Lyase/genetics/metabolism Pl; |
Notes: | "MedlineBera, Paramita Mukherjee, Chiranjit Mitra, Adinpunya eng Ireland 2017/02/09 Plant Sci. 2017 Mar; 256:25-38. doi: 10.1016/j.plantsci.2016.11.013. Epub 2016 Dec 2" |