Clostridial collagenases are among the most efficient degraders of eukaryotic collagen known; saprophytes use collagen as a carbon source while pathogens additionally digest collagen to aid in host colonization. Has both tripeptidylcarboxypeptidase on Gly-X-Y and endopeptidase activities; the endopeptidase cuts within the triple helix region of collagen while tripeptidylcarboxypeptidase successively digests the exposed ends, thus clostridial collagenases can digest large sections of collagen (By similarity). The activator domain (residues 57-330) and catalytic subdomain (340-611) open and close around substrate allowing digestion when the protein is closed (PubMed:23703618). Digestion of native collagen in the triple helical region at Xaa-|-Gly bonds. With synthetic peptides, a preference is shown for Gly at P3 and P1', Pro and Ala at P2 and P2', and hydroxyproline, Ala or Arg at P3'. Binds about 5 Ca(2+) per subunit (Probable). The metallopeptidase domain binds 1 Ca(2+), while each CDB binds 2 (Probable). Binds 1 catalytic Zn(2+) per subunit. Partially inhibited by 1-10-phenanthroline; inactivation is irreversible (PubMed:18937627, PubMed:23703618). Partially inhibited by EDTA; inactivation is reversible (PubMed:23703618). Inhibited by broad-spectrum zinc metalloprotease inhibitor batimastat (PubMed:28820255). N-aryl mercaptoacetamide-based inhibitors have been isolated that act on clostridial collagenases with submicromolar affinity while having negligibile activity on human collagenases (PubMed:28820255). kcat is 7.24/sec, using a catalytic fragment (residues 53-727) on an artificial substrate. The mature protein has 3 domains; a metalloprotease domain (S1, approximately residues 53 to 727) and 2 collagen-binding domains (CBD) (755-872) and (882-991) (PubMed:18937627). The metalloprotease S1 domain is composed of 3 subdomains which together resemble a saddle; an activator domain (residues 57-330), the catalytic peptidase subdomain (340-611) and a helper subdomain (619-731) (PubMed:23703618). N-aryl mercaptoacetamide-based inhibitors with submicromolar affinity for clostridial collagenases but negligibile activity on human collagenases have been discovered that may lead to promising anti-infective drugs against Clostridia (PubMed:28820255). Belongs to the peptidase M9B family. Collagenase subfamily.