Lyases are a broad class of enzyme that catalyze one simple function in biological systems; they help to engage the lysis of a substrate. They are different from another class of joining enzymes, Ligases, by the manner in which they catalyze lysis. The end product of a lyase reaction always involves the formation of a double bond. The reaction will be non-hydrolytic and non-oxidative, meaning that hydrolysis, oxidation, and reduction will not actively be involved in the process.