SAM:salicylic acid carboxyl methyltransferase; converts salicylic acid to methyl salicylate (winter
BBa_J45001 encodes SAM salicylic acid carboxyl methyltransferase I derived from SAMT from Antirrhinus majus (snapdragon). SAMT catalyzes the conversion of salicylic acid to methyl salicylate. Methyl salicylate has a wintergreen smell.
Usage and Biology
- The culture medium of E. coli cells expressing SAMT contained methyl salicylate (2.1 μg/ml) when the growing medium was supplemented with 5 μg/ml salicylic acid, and methyl benzoate (0.86 μg/ml) when the growing medium was supplemented with 5 μg/ml benzoic acid.
- E. coli-expressed SAMT catalyzes the formation of the volatile ester methyl salicylate from salicylic acid with a Km (salicylic acid) of 83 and a Km (SAM) of 3-4. SAMT can also methylate benzoic acid to form methyl benzoate, but its Km value for benzoic acid is 1720 M (much larger). kcat/Km for salicylic acid is 132 s-1 M-1, and activity with substrate benzoic acid is 45% of the activity with substrate salicylic acid. All other acids yield 0% activity.
Sequence and Features
- 10COMPATIBLE WITH RFC
- 12Illegal NheI site found at 577
- 21Illegal XhoI site found at 901
- 23COMPATIBLE WITH RFC
- 25Illegal NgoMIV site found at 421
Illegal NgoMIV site found at 425
- 1000Illegal SapI.rc site found at 75
Illegal SapI site found at 471