EC                Enzyme                                 

alternative-complement-pathway C3/C5 convertase;
complement component C3/C5 convertase (alternative);
proenzyme factor B;
properdin factor B;
C3 proactivator;
glycine-rich beta-glycoprotein;
heat-labile factor;
C3 convertase;
C3b,Bb,CVF,Bb,C5 convertase;
complement C 3(C 5) convertase (amplification);
alternative complement pathway C3(C5) convertase;
C5 convertase;
(CVF)-dependent glycine-rich-beta-glucoprotein;
cobra venom factor-dependent C3 convertase
Acting on peptide bonds (peptidases);
Serine endopeptidases
Cleavage of Arg!Ser bond in complement component C3 alpha-chain to yield C3a and C3b, and Arg! bond in complement component C5 alpha-chain to yield C5a and C5b
A bimolecular complex of complement fragment Bb with either C3b or cobra venom factor; Bb contains the active site. Bb is formed by cleavage of proenzyme factor B by factor D. Cleavage of complement component C5 requires additional C3b which binds C5 and renders it susceptible to cleavage by C3b,Bb complex. C3b,Bb is stabilized in plasma by factor P. Complement factor B is in peptidase family S1 (trypsin family)
EC created 1981
K01335  complement factor B
HSA: 629(CFB)
PTR: 494140(CFB)
PPS: 100990821(CFB)
GGO: 101141641(CFB)
PON: 103890868(CFB)
NLE: 100595765(CFB)
MCC: 716809(CFB)
MCF: 102133787(CFB)
CSAB: 108449896(CFB)
CATY: 105583239(CFB)
RRO: 104678121(CFB)
RBB: 108520262(CFB)
TFN: 117086976(CFB)
PTEH: 111523926
CJC: 100409227(CFB)
SBQ: 101036079(CFB)
MMUR: 105858159(CFB)
MMU: 14962(Cfb)
MCAL: 110312388(Cfb)
MPAH: 110336125(Cfb)
RNO: 294257(Cfb)
MCOC: 116075349(Cfb)
MUN: 110560137(Cfb)
CGE: 100758781(Cfb)
PLEU: 114705866(Cfb)
NGI: 108490121(Cfb)
HGL: 101725137(Cfb)
CCAN: 109689576(Cfb)
OCU: 100355944(CFB)
TUP: 102480574(CFB)
CFA: 100688056(CFB)
VVP: 112913626(CFB)
VLG: 121500776(CFB)
AML: 100474759(CFB)
UMR: 103682288(CFB)
UAH: 113243739(CFB)
ORO: 101378817(CFB)
ELK: 111152198
MPUF: 101692539(CFB)
EJU: 114222131(CFB)
MLX: 118027314(CFB)
FCA: 101093018(CFB)
PYU: 121022337(CFB)
PTG: 102969938(CFB)
PPAD: 109260506(CFB)
AJU: 106983483(CFB)
HHV: 120221920(CFB)
BTA: 514076(CFB)
BOM: 102267775(CFB)
BIU: 109576933(CFB)
BBUB: 102404663(CFB)
CHX: 102175816(CFB)
OAS: 101115072(CFB)
ODA: 120870573(CFB)
CCAD: 122429827(CFB)
SSC: 100124383(CFB)
CFR: 102519366(CFB)
CBAI: 105074040
CDK: 105087438(CFB)
BACU: 103017988(CFB)
LVE: 103071310(CFB)
OOR: 101281312(CFB)
DLE: 111170703(CFB)
PCAD: 102991673(CFB)
ECB: 100051124(CFB)
EPZ: 103563301(CFB)
EAI: 106831003(CFB)
MYB: 102262757(CFB)
MYD: 102766003(CFB)
MMYO: 118679565(CFB)
MNA: 107538978(CFB)
HAI: 109373064(CFB)
DRO: 112302049
SHON: 118979559(CFB)
AJM: 119053693(CFB)
MMF: 118621310(CFB)
PALE: 102877940(CFB)
PGIG: 120618897(CFB)
RAY: 107498437(CFB)
MJV: 108393990(CFB)
TOD: 119252230(CFB)
LAV: 100668025(CFB)
TMU: 101350698
MDO: 107648882(CFB)
PCW: 110199443(CFB)
PHI: 106628820(CFB)
AMJ: 102574048(CFB) 109280870
ACS: 100555786 100555981(cfb)
PVT: 110088690(CFB)
PBI: 103054626
PGUT: 117667853
PMUA: 114590977(CFB)
GJA: 107105481(CFB)
XLA: 108698939 373577(cfb.S) 397725(cfb.L)
XTR: 100491419(cfb)
NPR: 108786506
DRE: 30604(cfb) 792472(cfbl)
IPU: 100862742
LCO: 104929932
NCC: 104964654
ELY: 117272009
PLEP: 121952156
SLUC: 116064868
ECRA: 117955159
PFLV: 114566514
GAT: 120821357
MSAM: 119895101
CUD: 121518408
MZE: 101486732
ONL: 100707990
OLA: 100049430(bf/c2)
XCO: 114153817
XHE: 116727817
PRET: 103475468
CTUL: 119775850(bfb) 119775881
KMR: 108237014
ALIM: 106514073
AOCE: 111580649
CSEM: 103395154
POV: 109628349
LCF: 108893578
SDU: 111234364
SLAL: 111666299
XGL: 120802806
HCQ: 109517895
BPEC: 110158573
MALB: 109959265
OMY: 100136605(cfbl) 100653464 110534129(cfb)
SFM: 108934440(cfb) 108938433
AANG: 118234983(cfbl)
PSPA: 121299068(cfbl)
LCM: 102360252 102360987(CFB)
RTP: 109921430
BBEL: 109471260
CIN: 497244(bf-3)
SPU: 373308(bf)
SKO: 100373330
RSAN: 119395859
RMP: 119173521
PTEP: 107454561
ATEN: 116300929
PDAM: 113673827
SPIS: 111333045
 » show all
1  [PMID:7043188]
Kerr MA.
Human factor B.
Methods Enzymol 80 Pt C:102-12 (1981)
2  [PMID:6323161]
Morley BJ, Campbell RD.
Internal homologies of the Ba fragment from human complement component Factor B, a class III MHC antigen.
EMBO J 3:153-7 (1984)
3  [PMID:3052276]
Muller-Eberhard HJ.
Molecular organization and function of the complement system.
Annu Rev Biochem 57:321-47 (1988)
Other DBs
ExplorEnz - The Enzyme Database:
IUBMB Enzyme Nomenclature:
ExPASy - ENZYME nomenclature database:
BRENDA, the Enzyme Database:
CAS: 80295-67-6

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