Alpha-chymotrypsin (EC 3.4.21.1) is one of a family of serine proteases secreted into the gastrointestinal tract as the inactive precursor chymotrypsinogen. The zymogen is activated by proteolytic cleavage by trypsin. Alpha-chymotrypsin (EC 3.4.21.1) is one of a family of serine proteases secreted into the gastrointestinal tract as the inactive precursor chymotrypsinogen. The zymogen is activated by proteolytic cleavage by trypsin (PRSS1; MIM 276000).[supplied by OMIM]. PRIMARYREFSEQ_SPAN PRIMARY_IDENTIFIER PRIMARY_SPAN COMP 1-74 BX497259.1 1-74 75-652 CA946996.1 14-591 653-873 AW338596.1 1-221 c