Difference between revisions of "Part:BBa J45001"

Revision as of 21:44, 9 March 2008

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 K_m (salicylic acid) of 83 and a K_m (SAM) of 3-4. SAMT can also methylate benzoic acid to form methyl benzoate, but its K_m value for benzoic acid is 1720 M (much larger). k_cat/K_m 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

Assembly Compatibility:

10
COMPATIBLE WITH RFC[10]
12
INCOMPATIBLE WITH RFC[12]
Illegal NheI site found at 577
21
INCOMPATIBLE WITH RFC[21]
Illegal XhoI site found at 901
23
COMPATIBLE WITH RFC[23]
25
INCOMPATIBLE WITH RFC[25]
Illegal NgoMIV site found at 421
Illegal NgoMIV site found at 425
1000
INCOMPATIBLE WITH RFC[1000]
Illegal SapI site found at 471
Illegal SapI.rc site found at 75

Functional Parameters

ec_num	none
kegg	none
protein	SAMT
swisspro	Q8H6N2

@@ Line 5: / Line 5: @@
 ===Usage and Biology===
-The culture medium of ''E. coli'' cells expressing ''SAMT'' contained methyl salicylate (2.1 &mu;g/ml) when the growing medium was supplemented with 5 &mu;g/ml salicylic acid, and methyl benzoate (0.86 &mu;g/ml) when the growing medium was supplemented with 5 &mu;g/ml benzoic acid.
+*The culture medium of ''E. coli'' cells expressing ''SAMT'' contained methyl salicylate (2.1 &mu;g/ml) when the growing medium was supplemented with 5 &mu;g/ml salicylic acid, and methyl benzoate (0.86 &mu;g/ml) when the growing medium was supplemented with 5 &mu;g/ml benzoic acid.
+*'''E. coli'''-expressed SAMT catalyzes the formation of the volatile ester methyl salicylate from salicylic acid with a K<sub>m</sub> (salicylic acid) of 83 and a K<sub>m</sub> (SAM) of 3-4. SAMT can also methylate benzoic acid to form methyl benzoate, but its K<sub>m</sub> value for benzoic acid is 1720 M (much larger). k<sub>cat</sub>/K<sub>m</sub> for salicylic acid is 132 s<sup>-1</sup> M<sup>-1</sup>, and activity with substrate benzoic acid is 45% of the activity with substrate salicylic acid. All other acids yield 0% activity.
 <!-- -->