Names & Taxonomy

Uniprot ID:
P00751
Entry Name:
CFAB_HUMAN
Status:
reviewed
Protein Names:
Complement factor B (EC 3.4.21.47) (C3/C5 convertase) (Glycine-rich beta glycoprotein) (GBG) (PBF2) (Properdin factor B) [Cleaved into: Complement factor B Ba fragment; Complement factor B Bb fragment]
Gene Names:
CFB BF BFD
Gene Names Primary:
CFB
Organism:
Homo sapiens (Human)

Structure

Length:
764
Sequence:
MGSNLSPQLCLMPFILGLLSGGVTTTPWSLARPQGSCSLEGVEIKGGSFRLLQEGQALEYVCPSGFYPYPVQTRTCRSTGSWSTLKTQDQKTVRKAECRAIHCPRPHDFENGEYWPRSPYYNVSDEISFHCYDGYTLRGSANRTCQVNGRWSGQTAICDNGAGYCSNPGIPIGTRKVGSQYRLEDSVTYHCSRGLTLRGSQRRTCQEGGSWSGTEPSCQDSFMYDTPQEVAEAFLSSLTETIEGVDAEDGHGPGEQQKRKIVLDPSGSMNIYLVLDGSDSIGASNFTGAKKCLVNLIEKVASYGVKPRYGLVTYATYPKIWVKVSEADSSNADWVTKQLNEINYEDHKLKSGTNTKKALQAVYSMMSWPDDVPPEGWNRTRHVIILMTDGLHNMGGDPITVIDEIRDLLYIGKDRKNPREDYLDVYVFGVGPLVNQVNINALASKKDNEQHVFKVKDMENLEDVFYQMIDESQSLSLCGMVWEHRKGTDYHKQPWQAKISVIRPSKGHESCMGAVVSEYFVLTAAHCFTVDDKEHSIKVSVGGEKRDLEIEVVLFHPNYNINGKKEAGIPEFYDYDVALIKLKNKLKYGQTIRPICLPCTEGTTRALRLPPTTTCQQQKEELLPAQDIKALFVSEEEKKLTRKEVYIKNGDKKGSCERDAQYAPGYDKVKDISEVVTPRFLCTGGVSPYADPNTCRGDSGGPLIVHKRSRFIQVGVISWGVVDVCKNQKRQKQVPAHARDFHINLFQVLPWLKEKLQDEDLGFL
Proteomes:
UP000005640

Subcellular location

Subcellular Location:
Secreted.

Function

Function:
Factor B which is part of the alternate pathway of the complement system is cleaved by factor D into 2 fragments: Ba and Bb. Bb, a serine protease, then combines with complement factor 3b to generate the C3 or C5 convertase. It has also been implicated in proliferation and differentiation of preactivated B-lymphocytes, rapid spreading of peripheral blood monocytes, stimulation of lymphocyte blastogenesis and lysis of erythrocytes. Ba inhibits the proliferation of preactivated B-lymphocytes.
Catalytic Activity:
Cleavage of Arg-|-Ser bond in complement component C3 alpha-chain to yield C3a and C3b, and Arg-|-Xaa bond in complement component C5 alpha-chain to yield C5a and C5b.
Active Site:
ACT_SITE 526 526 Charge relay system.; ACT_SITE 576 576 Charge relay system.; ACT_SITE 699 699 Charge relay system.
Gene Ontology Go:
blood microparticle
extracellular exosome
extracellular region
extracellular space
plasma membrane
complement binding
serine-type endopeptidase activity
complement activation
complement activation, alternative pathway
innate immune response
regulation of complement activation
Gene Ontology Biological Process:
complement activation
complement activation, alternative pathway
innate immune response
regulation of complement activation
Gene Ontology Molecular Function:
complement binding
serine-type endopeptidase activity
Gene Ontology Cellular Component:
blood microparticle
extracellular exosome
extracellular region
extracellular space
plasma membrane
Keywords:
3D-structure
Alternative splicing
Cleavage on pair of basic residues
Complement alternate pathway
Complete proteome
Direct protein sequencing
Disease mutation
Disulfide bond
Glycation
Glycoprotein
Hemolytic uremic syndrome
Hydrolase
Immunity
Innate immunity
Polymorphism
Protease
Reference proteome
Repeat
Secreted
Serine protease
Signal
Sushi
Zymogen

Publication

PubMed ID:
2249879 8181962 8225386 8247029 14656967 14574404 15489334 6546754 6342610 6308626 6957884 6323161 3643061 2006911 16335952 19159218 24152280 10637221 17310251 19574954 16518403 17182750 20513133