| IED ID | IndEnz0002018293 |
| Enzyme Type ID | protease018293 |
| Protein Name |
Chymosin EC 3.4.23.4 |
| Gene Name | CYM |
| Organism | Camelus dromedarius (Dromedary) (Arabian camel) |
| Taxonomic Lineage | cellular organisms Eukaryota Opisthokonta Metazoa Eumetazoa Bilateria Deuterostomia Chordata Craniata Vertebrata Gnathostomata (jawed vertebrates) Teleostomi Euteleostomi Sarcopterygii Dipnotetrapodomorpha Tetrapoda Amniota Mammalia Theria Eutheria Boreoeutheria Laurasiatheria Artiodactyla Tylopoda Camelidae Camelus Camelus dromedarius (Dromedary) (Arabian camel) |
| Enzyme Sequence | MRCLVVLLAALALSQASGITRIPLHKGKTLRKALKERGLLEDFLQRQQYAVSSKYSSLGKVAREPLTSYLDSQYFGKIYIGTPPQEFTVVFDTGSSDLWVPSIYCKSNVCKNHHRFDPRKSSTFRNLGKPLSIHYGTGSMEGFLGYDTVTVSNIVDPNQTVGLSTEQPGEVFTYSEFDGILGLAYPSLASEYSVPVFDNMMDRHLVARDLFSVYMDRNGQGSMLTLGAIDPSYYTGSLHWVPVTLQQYWQFTVDSVTINGVAVACVGGCQAILDTGTSVLFGPSSDILKIQMAIGATENRYGEFDVNCGNLRSMPTVVFEINGRDYPLSPSAYTSKDQGFCTSGFQGDNNSELWILGDVFIREYYSVFDRANNRVGLAKAI |
| Enzyme Length | 381 |
| Uniprot Accession Number | Q9GK11 |
| Absorption | |
| Active Site | ACT_SITE 92; /evidence="ECO:0000255|PROSITE-ProRule:PRU01103, ECO:0000269|PubMed:23633601"; ACT_SITE 274; /evidence="ECO:0000255|PROSITE-ProRule:PRU01103, ECO:0000269|PubMed:23633601" |
| Activity Regulation | |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | CATALYTIC ACTIVITY: Reaction=Broad specificity similar to that of pepsin A. Clots milk by cleavage of a single 104-Ser-Phe-|-Met-Ala-107 bond in kappa-chain of casein.; EC=3.4.23.4; Evidence={ECO:0000269|PubMed:16488399, ECO:0000269|PubMed:23633601, ECO:0000269|PubMed:25726113, ECO:0000269|PubMed:25837439}; |
| DNA Binding | |
| EC Number | 3.4.23.4 |
| Enzyme Function | FUNCTION: Chymosin is synthesized in the mucosa of the abomasum (fourth stomach) of young (unweaned) ruminants (PubMed:16488399). The enzyme hydrolyzes casein to paracasein (PubMed:16488399, PubMed:23633601, PubMed:25726113, PubMed:25837439). {ECO:0000269|PubMed:16488399, ECO:0000269|PubMed:23633601, ECO:0000269|PubMed:25726113, ECO:0000269|PubMed:25837439}. |
| Temperature Dependency | BIOPHYSICOCHEMICAL PROPERTIES: Temperature dependence: Optimum temperature is between 45-55 degrees Celsius (PubMed:16488399, PubMed:25837439). 50% activity at 35 and 60 degrees Celsius. No activity below 20 or above 70 degrees Celsius (PubMed:25837439). {ECO:0000269|PubMed:16488399, ECO:0000269|PubMed:25837439}; |
| PH Dependency | BIOPHYSICOCHEMICAL PROPERTIES: pH dependence: Optimum pH is about 5.1 (PubMed:16488399). Activity decreases with increasing pH values (PubMed:25837439). {ECO:0000269|PubMed:16488399, ECO:0000269|PubMed:25837439}; |
| Pathway | |
| nucleotide Binding | |
| Features | Active site (2); Beta strand (24); Chain (1); Disulfide bond (3); Domain (1); Glycosylation (2); Helix (10); Propeptide (1); Signal peptide (1); Turn (3) |
| Keywords | 3D-structure;Aspartyl protease;Digestion;Direct protein sequencing;Disulfide bond;Glycoprotein;Hydrolase;Protease;Signal;Zymogen |
| Interact With | |
| Induction | |
| Subcellular Location | |
| Modified Residue | |
| Post Translational Modification | |
| Signal Peptide | SIGNAL 1..16; /evidence=ECO:0000250|UniProtKB:Q9N2D2 |
| Structure 3D | X-ray crystallography (1) |
| Cross Reference PDB | 4AA9; |
| Mapped Pubmed ID | - |
| Motif | |
| Gene Encoded By | |
| Mass | 42,083 |
| Kinetics | BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=56 uM for undecapeptide analog to chymosin sensitive region of camel kappa-chain of casein {ECO:0000269|PubMed:16488399}; KM=77 uM for undecapeptide analog to chymosin sensitive region of bovine kappa-chain of casein {ECO:0000269|PubMed:16488399}; KM=18 uM for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (unglycosylated form of chymosin at pH 6.7) {ECO:0000269|PubMed:25726113}; KM=11 uM for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (unglycosylated form of chymosin at pH 6.0) {ECO:0000269|PubMed:25726113}; KM=7 uM for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (unglycosylated form of chymosin at pH 5.5) {ECO:0000269|PubMed:25726113}; KM=20 uM for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (double-glycosylated form of chymosin at pH 6.7) {ECO:0000269|PubMed:25726113}; KM=11 uM for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (double-glycosylated form of chymosin at pH 6.0) {ECO:0000269|PubMed:25726113}; KM=8 uM for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (double-glycosylated form of chymosin at pH 5.5) {ECO:0000269|PubMed:25726113}; Note=kcat is 5.1 sec(-1) for undecapeptide analog to chymosin sensitive region of camel kappa-chain of casein and kcat is 11.7 sec(-1) for undecapeptide analog to chymosin sensitive region of bovine kappa-chain of casein (PubMed:16488399). Activity is 462 International Milk-Clotting Units (IMCU) per mg enzyme. kcat is 11 sec(-1) for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (unglycosylated form of chymosin at pH 6.7), kcat is 53 sec(-1) for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (unglycosylated form of chymosin at pH 6.0), kcat is 47 sec(-1) for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (unglycosylated form of chymosin at pH 5.5), kcat is 14 sec(-1) for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (double-glycosylated form of chymosin at pH 6.7), kcat is 65 sec(-1) for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (double-glycosylated form of chymosin at pH 6.0) and kcat is 59 sec(-1) for a labeled peptide substrate of 98-112 of bovine kappa-chain of casein (double-glycosylated form of chymosin at pH 5.5) (PubMed:25726113). Activity is 400 IMCU per ml enzyme. Supplemental CaCl(2) at concentration between 20-40 mM is optimal for stable enzyme activity (PubMed:25837439). {ECO:0000269|PubMed:16488399, ECO:0000269|PubMed:25726113, ECO:0000269|PubMed:25837439}; |
| Metal Binding | |
| Rhea ID | |
| Cross Reference Brenda | 3.4.23.4; |