Protease

A protease is a digestive  enzyme. It breaks down long chains of  proteins into shorter amino acids. Proteases have evolved a number of times. We know this because different kinds of protease can do the same reaction in completely different ways. Proteases are found in animals, plants, bacteria, archaea and viruses.

Now more than 50 types of protease are known. Each is a separate evolutionary origin of proteolysis.MEROPS, the peptide database.  

Protease can be divided into 6 types :
serine proteases
threonine proteases
cysteine proteases
aspartate proteases
metallo proteases
glutamic acid proteases

 References 

Category:Enzymes