| Title: | "Novel S-adenosyl-L-methionine:salicylic acid carboxyl methyltransferase, an enzyme responsible for biosynthesis of methyl salicylate and methyl benzoate, is not involved in floral scent production in snapdragon flowers" |
| Author(s): | Negre F; Kolosova N; Knoll J; Kish CM; Dudareva N; |
| Address: | "Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907, USA" |
| DOI: | 10.1016/s0003-9861(02)00458-7 |
| ISSN/ISBN: | 0003-9861 (Print) 0003-9861 (Linking) |
| Abstract: | "Using a functional genomic approach we have isolated and characterized a cDNA that encodes a salicylic acid carboxyl methyltransferase (SAMT) from Antirrhinum majus. The sequence of the protein encoded by SAMT has higher amino acid identity to Clarkia breweri SAMT than to snapdragon benzoic acid carboxyl methyltransferase (BAMT) (55 and 40% amino acid identity, respectively). Escherichia coli-expressed SAMT protein catalyzes the formation of the volatile ester methyl salicylate from salicylic acid with a K(m) value of 83 microM. It can also methylate benzoic acid to form methyl benzoate, but its K(m) value for benzoic acid is 1.72 mM. Snapdragon flowers do not emit methyl salicylate. The potential involvement of SAMT in production and emission of methyl benzoate in snapdragon flowers was analyzed by RNA gel blot analysis. SAMT mRNA was not detected in floral tissues by RNA blot hybridization, but low levels of SAMT gene expression were detected after real-time RT-PCR in the presence of SAMT-specific primers, indicating that this gene does not contribute significantly, if at all, in methyl benzoate production and emission in snapdragon flowers. Expression of SAMT in petal tissue was found to be induced by salicylic and jasmonic acid treatments" |
| Keywords: | "Amino Acid Sequence Antirrhinum/*enzymology Benzoates/*pharmacokinetics Cloning, Molecular DNA Primers Escherichia coli/enzymology/genetics Flowers/*physiology Kinetics Methyltransferases/chemistry/genetics/*metabolism Molecular Sequence Data Molecular We;" |
| Notes: | "MedlineNegre, Florence Kolosova, Natalia Knoll, Joseph Kish, Christine M Dudareva, Natalia eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2002/10/04 Arch Biochem Biophys. 2002 Oct 15; 406(2):261-70. doi: 10.1016/s0003-9861(02)00458-7" |
