Reviewed, UniProtKB/Swiss-Prot P81187 (CFAB_BOVIN)

Names and origin

Protein names

Recommended name:
    Complement factor B
    EC=3.4.21.47
Alternative name(s):
    C3/C5 convertase
    EC-VMFB
Cleaved into the following 2 chains:
    1- Recommended name:
            Complement factor B Ba fragment
    2- Recommended name:
            Complement factor B Bb fragment

Gene names

Name:	CFB
Synonyms:	BF

Organism

Bos taurus (Bovine)

Taxonomic identifier

9913 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Laurasiatheria › Cetartiodactyla › Ruminantia › Pecora › Bovidae › Bovinae › Bos

Protein attributes

Sequence length	761 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

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.
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.
Subunit structure	Monomer By similarity.
Subcellular location	Secreted.
Sequence similarities	Belongs to the peptidase S1 family. Contains 1 peptidase S1 domain. Contains 3 Sushi (CCP/SCR) domains. Contains 1 VWFA domain.

Ontologies

Keywords
Biological process	Complement alternate pathway Immune response Innate immunity
Cellular component	Secreted
Domain	Repeat Signal Sushi
Molecular function	Hydrolase Protease Serine protease
PTM	Cleavage on pair of basic residues Disulfide bond Glycoprotein Zymogen
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	complement activation, alternative pathway Inferred from electronic annotation. Source: UniProtKB-KW proteolysis Inferred from electronic annotation. Source: InterPro
Cellular component	extracellular region Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	serine-type endopeptidase activity Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Signal peptide	1 – 25	25	By similarity
	Chain	26 – 761	736	Complement factor B		PRO_0000285857
	Chain	26 – 259	234	Complement factor B Ba fragment		PRO_0000285858
	Chain	260 – 761	502	Complement factor B Bb fragment		PRO_0000027541
Regions
	Domain	35 – 100	66	Sushi 1
	Domain	101 – 160	60	Sushi 2
	Domain	163 – 220	58	Sushi 3
	Domain	270 – 469	200	VWFA
	Domain	477 – 754	278	Peptidase S1
Sites
	Active site	526	1	Charge relay system By similarity
	Active site	576	1	Charge relay system By similarity
	Active site	699	1	Charge relay system By similarity
Amino acid modifications
	Glycosylation	122	1	N-linked (GlcNAc...) Potential
	Glycosylation	142	1	N-linked (GlcNAc...) Potential
	Glycosylation	285	1	N-linked (GlcNAc...) Potential
	Glycosylation	378	1	N-linked (GlcNAc...) Potential
	Disulfide bond	37 ↔ 76		By similarity
	Disulfide bond	62 ↔ 98		By similarity
	Disulfide bond	103 ↔ 145		By similarity
	Disulfide bond	131 ↔ 158		By similarity
	Disulfide bond	165 ↔ 205		By similarity
	Disulfide bond	191 ↔ 218		By similarity
	Disulfide bond	511 ↔ 527		By similarity
	Disulfide bond	695 ↔ 725		By similarity

Sequences

	Sequence		Length	Mass (Da)
	P81187-1 [UniParc]. Last modified May 1, 2007. Version 2. Checksum: 9802026064256687	FASTA	761	85,366
	10 20 30 40 50 60 MGIGHNPRLC LVPLILGLLC GGVGMTPLPE AGPQSPCSLE GVEIKGGSFR LLKAGQVLEY 70 80 90 100 110 120 LCPSGFYPYP TQIRTCRSTG SWSTLQTQDR KIVKRAECKA IRCPRPQDFE NGEYWPRAAY 130 140 150 160 170 180 YNLSDEISFR CYDGYTLRGS ANRTCQGNGR WDGETAICDD GATYCPNPGI PLGTRKVGSQ 190 200 210 220 230 240 YRLEDRVTYY CNRGLTLRGS EQRTCLEGGS WSGTEPSCQD SFMYDTPAEV AEAFLSSLTE 250 260 270 280 290 300 TIEGVDAEDG HSPGEQQKRK IVLDPSGSMN IYLVLDGSDS VGAHNFTGAK NCLRDFIEKV 310 320 330 340 350 360 ASYGVKPKYG LVTYATEPKV LIRVSDPKSS EADWVTDQLN QINYADHKLK AGTNTKRALL 370 380 390 400 410 420 EVYNMMSREV NQFKETWNRT RHVIIIMTDG LHNMGGDPVT VIHDIRYLLD IGRNRKNPRE 430 440 450 460 470 480 DYLDIYVFGV GPLVNQENIN ALASKKDKEK HVFKLQGMEN LEDVFVQMLD ESRTLGLCGM 490 500 510 520 530 540 VWEHKDGTAY HKQPWQAKIS VTRPSKGHES CMGAIVSEYF VLTAAHCFTV DDEKHSIKVS 550 560 570 580 590 600 LGGQRKEWEV KEILFHPKYD LNAKKAKGIP EFYDYDVALV RLKEKLKYET TIRPICLPCT 610 620 630 640 650 660 EGSIQALRLP RSTTCQQQMQ ELLPAKDIEA LFVSESKKTL TRKAVYIKNG DKKASCERDA 670 680 690 700 710 720 LRAPGYEKVK DVSEVVTPRF LCTGGVDPYA DPNTCKGDSG GPLIIHKRSR FIQVGVISWG 730 740 750 760 VVDVCKRPQQ VPGYARDFHI NLYQVLPWLK EKLQNEDLGF L

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	NIH - Mammalian Gene Collection (MGC) project Submitted (JAN-2006) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Strain: Hereford. Tissue: Testis.
[2]	"Isolation from fetal bovine serum of a fragment b of complement factor B-like protein improving a long-term survival of human endothelial cells." Cai G., Satoh T., Hoshi H. Arch. Biochem. Biophys. 345:150-155(1997) [PubMed: 9281322] [Abstract] Cited for: PROTEIN SEQUENCE OF 260-275. Tissue: Blood.

Cross-references

Sequence databases
EMBLGenBankDDBJ	BC112504 mRNA. Translation: AAI12505.1.
IPI	IPI00717527.
RefSeq	NP_001035616.1.
UniGene	Bt.13542
3D structure databases
SMR	P81187. Positions 34-761.
ModBase	Search...
Genome annotation databases
Ensembl	ENSBTAG00000007450. Bos taurus. [Contig view]
GeneID	514076.
KEGG	bta:514076.
Phylogenomic databases
HOVERGEN	P81187.
OMA	P81187. KTACERD.
Enzyme and pathway databases
BRENDA	3.4.21.47. 251.
Family and domain databases
InterPro	IPR011360. Compl_C2_B. IPR016060. Complement_control_module. IPR018114. Peptidase_S1/S6_AS. IPR001254. Peptidase_S1_S6. IPR001314. Peptidase_S1A. IPR000436. Sushi_SCR_CCP. IPR002035. VWF_A. [Graphical view]
Gene3D	G3DSA:2.10.70.10. Complement_control_module. 2 hits.
Pfam	PF00084. Sushi. 2 hits. PF00089. Trypsin. 1 hit. PF00092. VWA. 1 hit. [Graphical view]
PIRSF	PIRSF001154. Compl_C2_B. 1 hit.
PRINTS	PR00722. CHYMOTRYPSIN.
SMART	SM00032. CCP. 3 hits. SM00020. Tryp_SPc. 1 hit. SM00327. VWA. 1 hit. [Graphical view]
PROSITE	PS50923. SUSHI. 3 hits. PS50240. TRYPSIN_DOM. 1 hit. PS00134. TRYPSIN_HIS. 1 hit. PS00135. TRYPSIN_SER. 1 hit. PS50234. VWFA. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

CFAB_BOVIN

Accession

Primary (citable) accession number: P81187
Secondary accession number(s): Q2KIU6

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 15, 1998
Last sequence update:	May 1, 2007
Last modified:	June 16, 2009
This is version 59 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)