Detail Information for IndEnz0002004774
IED ID IndEnz0002004774
Enzyme Type ID protease004774
Protein Name Complement factor I
EC 3.4.21.45
C3B/C4B inactivator

Cleaved into: Complement factor I heavy chain; Complement factor I light chain
Gene Name Cfi If
Organism Mus musculus (Mouse)
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 Euarchontoglires Glires (Rodents and rabbits) Rodentia Myomorpha (mice and others) Muroidea Muridae Murinae Mus Mus Mus musculus (Mouse)
Enzyme Sequence MKLAHLSLFLLALHLSSSRSPSASDLPQEELVDQKCLLQKYTHRSCNKVFCQPWQRCIEGTCICKLPYQCPRAGTPVCAMNGRSYPTYCHQKSFECLHPEIKFSHNGTCAAEGKFNVSLIYGRTKTEGLVQVKLVDQDERMFICKNSWSMAEANVACVDLGFPLGVRDIQGSFNISGNLHINDTECLHVHCRGVETSLAECAFTKRRTELSNGLAGVVCYKQDADFPTSLSFQCVNGKHIPQEKACNGVNDCGDQSDELCCKGCRGNASLCKSGVCIPDQYKCNGEVDCITGEDESRCEEDRQQNIPKGLARSAQGEAEIETEETEMLTPGMDNERKRIKSLLPKLSCGVKRNTHTRRKRVIGGKPANVGDYPWQVAIKDGQRITCGGIYIGGCWILTAAHCVRPSRAHSYQVWTALLDWLKPNSQLGIQTVKRVIVHEKYNGATFQNDIALIEMKMHTGKKECELPNSVPACVPWSPYLFQPNDRCIISGWGRGKDNQKVYSLRWGEVDLIGNCSQFYPDRYYEKEMQCAGTRDGSIDACKGDSGGPLVCEDINNVTYVWGIVSWGENCGKPEFPGVYTRVANYFDWISYHVGRSLVSQHNV
Enzyme Length 603
Uniprot Accession Number Q61129
Absorption
Active Site ACT_SITE 401; /note=Charge relay system; /evidence=ECO:0000250|UniProtKB:P00750; ACT_SITE 449; /note=Charge relay system; /evidence=ECO:0000250|UniProtKB:P00750; ACT_SITE 545; /note=Charge relay system; /evidence=ECO:0000250|UniProtKB:P00750
Activity Regulation
Binding Site
Calcium Binding CA_BIND 244..258; /evidence=ECO:0000250; CA_BIND 281..295; /evidence=ECO:0000250
catalytic Activity CATALYTIC ACTIVITY: Reaction=Inactivates complement subcomponents C3b, iC3b and C4b by proteolytic cleavage.; EC=3.4.21.45;
DNA Binding
EC Number 3.4.21.45
Enzyme Function FUNCTION: Trypsin-like serine protease that plays an essential role in regulating the immune response by controlling all complement pathways. Inhibits these pathways by cleaving three peptide bonds in the alpha-chain of C3b and two bonds in the alpha-chain of C4b thereby inactivating these proteins. Essential cofactors for these reactions include factor H and C4BP in the fluid phase and membrane cofactor protein/CD46 and CR1 on cell surfaces. The presence of these cofactors on healthy cells allows degradation of deposited C3b by CFI in order to prevent undesired complement activation, while in apoptotic cells or microbes, the absence of such cofactors leads to C3b-mediated complement activation and subsequent opsonization. {ECO:0000250|UniProtKB:P05156}.
Temperature Dependency
PH Dependency
Pathway
nucleotide Binding
Features Active site (3); Calcium binding (2); Chain (3); Disulfide bond (21); Domain (5); Glycosylation (7); Sequence conflict (3); Signal peptide (1)
Keywords Calcium;Cleavage on pair of basic residues;Complement pathway;Disulfide bond;Glycoprotein;Hydrolase;Immunity;Innate immunity;Metal-binding;Protease;Reference proteome;Repeat;Secreted;Serine protease;Signal
Interact With
Induction
Subcellular Location SUBCELLULAR LOCATION: Secreted, extracellular space {ECO:0000250|UniProtKB:P05156}.
Modified Residue
Post Translational Modification
Signal Peptide SIGNAL 1..18; /evidence=ECO:0000255
Structure 3D
Cross Reference PDB -
Mapped Pubmed ID 10583609; 12618913; 18167345; 21267068; 23341629; 24006456; 24194600; 24474777; 27626380;
Motif
Gene Encoded By
Mass 67,261
Kinetics
Metal Binding
Rhea ID
Cross Reference Brenda 3.4.21.45;