Team:UNITN-Trento/Project/Methyl Salicylate
From 2013.igem.org
It was difficult to find a volatile molecule that could be enzymatically produced by a bacterium and also demonstrated to be an efficient ripening inhbitor. There were not many candidates to choose from and after a long search we chose methyl salicylate (MeSA). Previous publications suggested that MeSA could inhibit the ripening of either kiwifruit and tomatoes, at a concentration of 0.5 mM (Ding, C. and Wang, Plant Science 2003, Y. 164 pp. 589-596.) (Aghdam M. et al., Journal of Agricultural Science. June 2011, Vol. 3, 2, pp. 149-156.)
Fortunately many of the needed parts were already available because of the work of the MIT iGEM 2006 team (Eau de Coli).
![](https://static.igem.org/mediawiki/2013/d/dd/Tn-2013_MeSA_path.jpg)
We modified and improved these parts and resubmitted them to the registry, as they were not available in pSB1C3.
![](https://static.igem.org/mediawiki/2013/4/41/Tn-2013_Mesa_main_parts.jpg)
To have a quantitative analysis we used a Finnigan Trace GC ULTRA with a flame ionization detector (FID) that allowed us to detect ions formed during MeSA combustion in a hydrogen flame. The generation of this ions is proportional to MeSA concentration in the sample stream. A calibration curve was initially created using samples with a well known pure MeSA concentration (0 mM, 0.2 mM, 0.5 mM, 1.0 mM, 2 mM).
![](https://static.igem.org/mediawiki/2013/d/d4/Induced_sample_produce_MeSA.png)