Is there any tool to search the biochemical action of a particular enzyme in a metabolic pathway of an organism? In other words, how can I find if enzyme "E" is involved in the metabolic pathway for organism "X".
I think the KEGG pathway database may be of some use to you.
Link is here: http://www.genome.jp/kegg/pathway.html
This a database of manually drawn pathway maps, I have used the site myself and it is very useful in determining if your enzyme is in a pathway and where it lies in it. This is assuming though, your enzyme is in the database and has been mapped.