Arecombinant streptococcalC5apeptidasewas expressed in Escherichia coliand its catalytic properties and thermal sta-bility were subjected to examination. It was shown that the NH2 -terminal region ofC5a peptidase (Asn32–Asp79/ Lys90) forms the pro-sequence segment. Upon maturation the propeptide is hydrolyzed either via an autocatalytic intramolecular cleavage or by exogenous protease strepto-pain. At pH the enzyme exhibited maximum activity in the narrow range oftemperatures between 40 and 43 C
