› › Function and Biology

Cobra Venom Factor (CVF) in complex with human factor B

Source organisms:
Biochemical function: endopeptidase inhibitor activity
Biological process: innate immune response
Cellular component: extracellular region

Quick links

EC 3.4.21.47: Alternative-complement-pathway C3/C5 convertase

Reaction catalysed:
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.
Alternative Name(s):
  • (C3b)(n),Bb
  • (CVF)-dependent glycine-rich-beta-glucoprotein
  • Alternative complement pathway C3(C5) convertase
  • C3 convertase
  • C3 proactivator
  • C3b,Bb,CVF,Bb,C5 convertase
  • C5 convertase
  • CVF,Bb
  • Cobra venom factor-dependent C3 convertase
  • Complement C 3(C 5) convertase (amplification)
  • Complement component C3/C5 convertase (alternative)
  • Complement factor B
  • Glycine-rich beta-glycoprotein
  • Heat-labile factor
  • Proenzyme factor B
  • Properdin factor B

GO terms

Sequence families

Pfam Protein families (Pfam)
PF00084
Domain description: Sushi repeat (SCR repeat)
Occurring in:
  1. Complement factor B
The deposited structure of PDB entry 3hs0 contains 6 copies of Pfam domain PF00084 (Sushi repeat (SCR repeat)) in Complement factor B. Showing 3 copies in chain H [auth I].

PF00089
Domain description: Trypsin
Occurring in:
  1. Complement factor B
The deposited structure of PDB entry 3hs0 contains 2 copies of Pfam domain PF00089 (Trypsin) in Complement factor B. Showing 1 copy in chain H [auth I].

PF00092
Domain description: von Willebrand factor type A domain
Occurring in:
  1. Complement factor B
The deposited structure of PDB entry 3hs0 contains 2 copies of Pfam domain PF00092 (von Willebrand factor type A domain) in Complement factor B. Showing 1 copy in chain H [auth I].

PF01759
Domain description: UNC-6/NTR/C345C module
Occurring in:
  1. Cobra venom factor beta chain
The deposited structure of PDB entry 3hs0 contains 2 copies of Pfam domain PF01759 (UNC-6/NTR/C345C module) in Cobra venom factor beta chain. Showing 1 copy in chain G [auth H].

PF07677
Domain description: A-macroglobulin receptor binding domain
Occurring in:
  1. Cobra venom factor beta chain
The deposited structure of PDB entry 3hs0 contains 2 copies of Pfam domain PF07677 (A-macroglobulin receptor binding domain) in Cobra venom factor beta chain. Showing 1 copy in chain G [auth H].

PF21308
Domain description: Complement component 3, CUB domain 2
Occurring in:
  1. Cobra venom factor beta chain

PF21406
Domain description: Complement component 3, CUB domain 1
Occurring in:
  1. Cobra venom factor gamma chain

PF00207
Domain description: Alpha-2-macroglobulin family
Occurring in:
  1. Cobra venom factor gamma chain
The deposited structure of PDB entry 3hs0 contains 2 copies of Pfam domain PF00207 (Alpha-2-macroglobulin family) in Cobra venom factor gamma chain. Showing 1 copy in chain B.

PF07703
Domain description: Alpha-2-macroglobulin bait region domain
Occurring in:
  1. Cobra venom factor alpha chain
The deposited structure of PDB entry 3hs0 contains 2 copies of Pfam domain PF07703 (Alpha-2-macroglobulin bait region domain) in Cobra venom factor alpha chain. Showing 1 copy in chain E [auth F].

PF17789
Domain description: Macroglobulin domain MG4
Occurring in:
  1. Cobra venom factor alpha chain
The deposited structure of PDB entry 3hs0 contains 2 copies of Pfam domain PF17789 (Macroglobulin domain MG4) in Cobra venom factor alpha chain. Showing 1 copy in chain E [auth F].

PF17791
Domain description: Macroglobulin domain MG3
Occurring in:
  1. Cobra venom factor alpha chain
The deposited structure of PDB entry 3hs0 contains 2 copies of Pfam domain PF17791 (Macroglobulin domain MG3) in Cobra venom factor alpha chain. Showing 1 copy in chain E [auth F].

PF01835
Domain description: MG2 domain
Occurring in:
  1. Cobra venom factor alpha chain
The deposited structure of PDB entry 3hs0 contains 2 copies of Pfam domain PF01835 (MG2 domain) in Cobra venom factor alpha chain. Showing 1 copy in chain E [auth F].

PF17790
Domain description: Macroglobulin domain MG1
Occurring in:
  1. Cobra venom factor alpha chain
The deposited structure of PDB entry 3hs0 contains 2 copies of Pfam domain PF17790 (Macroglobulin domain MG1) in Cobra venom factor alpha chain. Showing 1 copy in chain E [auth F].

InterPro InterPro annotations
IPR000436
Domain description: Sushi/SCR/CCP domain
Occurring in:
  1. Complement factor B
IPR001254
Domain description: Serine proteases, trypsin domain
Occurring in:
  1. Complement factor B
IPR001314
Domain description: Peptidase S1A, chymotrypsin family
Occurring in:
  1. Complement factor B
IPR002035
Domain description: von Willebrand factor, type A
Occurring in:
  1. Complement factor B
IPR035976
Domain description: Sushi/SCR/CCP superfamily
Occurring in:
  1. Complement factor B
IPR036465
Domain description: von Willebrand factor A-like domain superfamily
Occurring in:
  1. Complement factor B
IPR011360
Domain description: Complement B/C2
Occurring in:
  1. Complement factor B
IPR018933
Domain description: Netrin module, non-TIMP type
Occurring in:
  1. Cobra venom factor beta chain
IPR008993
Domain description: Tissue inhibitor of metalloproteinases-like, OB-fold
Occurring in:
  1. Cobra venom factor beta chain
IPR009048
Domain description: Alpha-macroglobulin, receptor-binding
Occurring in:
  1. Cobra venom factor beta chain
IPR036595
Domain description: Alpha-macroglobulin, receptor-binding domain superfamily
Occurring in:
  1. Cobra venom factor beta chain
IPR011625
Domain description: Alpha-2-macroglobulin, bait region domain
Occurring in:
  1. Cobra venom factor alpha chain
IPR013783
Domain description: Immunoglobulin-like fold
Occurring in:
  1. Cobra venom factor alpha chain
  2. Cobra venom factor gamma chain
IPR033116
Domain description: Serine proteases, trypsin family, serine active site
Occurring in:
  1. Complement factor B
IPR018114
Domain description: Serine proteases, trypsin family, histidine active site
Occurring in:
  1. Complement factor B
IPR009003
Domain description: Peptidase S1, PA clan
Occurring in:
  1. Complement factor B
IPR001134
Domain description: Netrin domain
Occurring in:
  1. Cobra venom factor beta chain
IPR035815
Domain description: Complement C3-like, NTR domain
Occurring in:
  1. Cobra venom factor beta chain
IPR014756
Domain description: Immunoglobulin E-set
Occurring in:
  1. Cobra venom factor gamma chain
IPR001599
Domain description: Alpha-2-macroglobulin
Occurring in:
  1. Cobra venom factor gamma chain
IPR040839
Domain description: Macroglobulin domain MG4
Occurring in:
  1. Cobra venom factor alpha chain
IPR041555
Domain description: Macroglobulin domain MG3
Occurring in:
  1. Cobra venom factor alpha chain
IPR002890
Domain description: Macroglobulin domain
Occurring in:
  1. Cobra venom factor alpha chain
IPR041425
Domain description: Complement C3/4/5, macroglobulin domain MG1
Occurring in:
  1. Cobra venom factor alpha chain

Structure domains

CATH CATH domains
2.60.40.1930
Class: Mainly Beta
Architecture: Sandwich
Topology: Immunoglobulin-like
Homology: Immunoglobulin-like
Occurring in:
  1. Cobra venom factor alpha chain
The deposited structure of PDB entry 3hs0 contains 6 copies of CATH domain 2.60.40.1930 (Immunoglobulin-like) in Cobra venom factor alpha chain. Showing 3 copies in chain E [auth F].
2.60.40.10
Class: Mainly Beta
Architecture: Sandwich
Topology: Immunoglobulin-like
Homology: Immunoglobulins
Occurring in:
  1. Cobra venom factor alpha chain
  2. Cobra venom factor gamma chain
The deposited structure of PDB entry 3hs0 contains 2 copies of CATH domain 2.60.40.10 (Immunoglobulin-like) in Cobra venom factor alpha chain. Showing 1 copy in chain E [auth F].
The deposited structure of PDB entry 3hs0 contains 2 copies of CATH domain 2.60.40.10 (Immunoglobulin-like) in Cobra venom factor gamma chain. Showing 1 copy in chain B.
2.40.50.120
Class: Mainly Beta
Architecture: Beta Barrel
Topology: OB fold (Dihydrolipoamide Acetyltransferase, E2P)
Homology: OB fold (Dihydrolipoamide Acetyltransferase, E2P)
Occurring in:
  1. Cobra venom factor beta chain
The deposited structure of PDB entry 3hs0 contains 2 copies of CATH domain 2.40.50.120 (OB fold (Dihydrolipoamide Acetyltransferase, E2P)) in Cobra venom factor beta chain. Showing 1 copy in chain G [auth H].
2.60.40.690
Class: Mainly Beta
Architecture: Sandwich
Topology: Immunoglobulin-like
Homology: Alpha-macroglobulin, receptor-binding domain
Occurring in:
  1. Cobra venom factor beta chain
The deposited structure of PDB entry 3hs0 contains 2 copies of CATH domain 2.60.40.690 (Immunoglobulin-like) in Cobra venom factor beta chain. Showing 1 copy in chain G [auth H].
2.20.210.20
Class: Mainly Beta
Architecture: Single Sheet
Topology: ubp-family deubiquitinating enzyme fold
Homology: ubp-family deubiquitinating enzyme fold
Occurring in:
  1. Cobra venom factor beta chain
The deposited structure of PDB entry 3hs0 contains 2 copies of CATH domain 2.20.210.20 (ubp-family deubiquitinating enzyme fold) in Cobra venom factor beta chain. Showing 1 copy in chain G [auth H].
2.20.130.20
Class: Mainly Beta
Architecture: Single Sheet
Topology: S-adenosyl-L-methionine-dependent methyltransferases
Homology: S-adenosyl-L-methionine-dependent methyltransferases
Occurring in:
  1. Cobra venom factor gamma chain
The deposited structure of PDB entry 3hs0 contains 2 copies of CATH domain 2.20.130.20 (S-adenosyl-L-methionine-dependent methyltransferases) in Cobra venom factor gamma chain. Showing 1 copy in chain B.
6.20.50.160
Class: Special
Architecture: Other non-globular
Topology: N-terminal domain of TfIIb
Homology: N-terminal domain of TfIIb
Occurring in:
  1. Cobra venom factor alpha chain
The deposited structure of PDB entry 3hs0 contains 2 copies of CATH domain 6.20.50.160 (N-terminal domain of TfIIb) in Cobra venom factor alpha chain. Showing 1 copy in chain E [auth F].
2.60.40.1940
Class: Mainly Beta
Architecture: Sandwich
Topology: Immunoglobulin-like
Homology: Immunoglobulin-like
Occurring in:
  1. Cobra venom factor alpha chain
The deposited structure of PDB entry 3hs0 contains 2 copies of CATH domain 2.60.40.1940 (Immunoglobulin-like) in Cobra venom factor alpha chain. Showing 1 copy in chain E [auth F].

Quick links