In enviPath, reaction objects represent biotransformation reactions from educt compound(s) to product compound(s). Reactions are directly linked to the involved compounds. A link from a rule to a reaction indicates that a reaction is in agreement with the generalized biotransformation rule.

Additionally, meta-information like experimental conditions or enzymes can be stored with a reaction. Enzyme information can be used to link out to enzyme databases such as KEGG or BRENDA.

A list of all available reactions is provided here: http://envipath.org/reaction. To view all reactions of a particular package, select the package first, then the reactions within this package (http://envipath.org/package/<id>/reaction).

Reactions can be created manually by drawing them with the Ketcher chemical structure editor or by providing the SMIRKS.

Alternatively, reactions are created during Pathway prediction, where each edge in the pathway corresponds to a reaction.