Function and Biology

Mistletoe Lectin I from Viscum album in Complex with Adenine Monophosphate. Crystal Structure at 1.9 A Resolution

Source organism: Viscum album
Biochemical function: rRNA N-glycosylase activity
Biological process: negative regulation of translation
Cellular component: not assigned

EC 3.2.2.22: rRNA N-glycosylase

Reaction catalysed:
Endohydrolysis of the N-glycosidic bond at one specific adenosine on the 28S rRNA.
Systematic name:
rRNA N-glycohydrolase
Alternative Name(s):
  • Gelonin
  • Mirabilis antiviral protein
  • Momorcochin-S
  • Nigrin b
  • RNA N-glycosidase
  • Ribosomal ribonucleate N-glycosidase
  • Ricin
  • Saporins
  • rRNA N-glycosidase

GO terms

Biochemical function:
Biological process:
Cellular component:
  • not assigned

Sequence families

Pfam Protein families (Pfam)
PF00652
Domain description: Ricin-type beta-trefoil lectin domain
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain B
The deposited structure of PDB entry 1m2t contains 2 copies of Pfam domain PF00652 (Ricin-type beta-trefoil lectin domain) in Beta-galactoside-specific lectin 1 chain B. Showing 2 copies in chain B.

PF00161
Domain description: Ribosome inactivating protein
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain A isoform 1
The deposited structure of PDB entry 1m2t contains 1 copy of Pfam domain PF00161 (Ribosome inactivating protein) in Beta-galactoside-specific lectin 1 chain A isoform 1. Showing 1 copy in chain A.

InterPro InterPro annotations
IPR000772
Domain description: Ricin B, lectin domain
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain B
IPR017989
Domain description: Ribosome-inactivating protein type 1/2
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain A isoform 1
IPR035992
Domain description: Ricin B-like lectins
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain B
IPR001574
Domain description: Ribosome-inactivating protein
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain A isoform 1
IPR016139
Domain description: Ribosome-inactivating protein, subdomain 2
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain A isoform 1
IPR036041
Domain description: Ribosome-inactivating protein superfamily
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain A isoform 1
IPR016138
Domain description: Ribosome-inactivating protein, subdomain 1
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain A isoform 1

Structure domains

CATH CATH domains
2.80.10.50
Class: Mainly Beta
Architecture: Trefoil
Topology: Trefoil (Acidic Fibroblast Growth Factor, subunit A)
Homology: Trefoil (Acidic Fibroblast Growth Factor, subunit A)
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain B
The deposited structure of PDB entry 1m2t contains 2 copies of CATH domain 2.80.10.50 (Trefoil (Acidic Fibroblast Growth Factor, subunit A)) in Beta-galactoside-specific lectin 1 chain B. Showing 2 copies in chain B.
4.10.470.10
Class: Few Secondary Structures
Architecture: Irregular
Topology: Ricin (A Subunit), domain 2
Homology: Ricin (A Subunit), domain 2
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain A isoform 1
The deposited structure of PDB entry 1m2t contains 1 copy of CATH domain 4.10.470.10 (Ricin (A Subunit), domain 2) in Beta-galactoside-specific lectin 1 chain A isoform 1. Showing 1 copy in chain A.
3.40.420.10
Class: Alpha Beta
Architecture: 3-Layer(aba) Sandwich
Topology: Ricin (A subunit); domain 1
Homology: Ricin (A subunit), domain 1
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain A isoform 1
The deposited structure of PDB entry 1m2t contains 1 copy of CATH domain 3.40.420.10 (Ricin (A subunit); domain 1) in Beta-galactoside-specific lectin 1 chain A isoform 1. Showing 1 copy in chain A.
SCOP SCOP annotations
50371
Class: All beta proteins
Fold: beta-Trefoil
Superfamily: Ricin B-like lectins
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain B
The deposited structure of PDB entry 1m2t contains 2 copies of SCOP domain 50371 (Ricin B-like) in Beta-galactoside-specific lectin 1 chain B. Showing 2 copies in chain B.
56372
Class: Alpha and beta proteins (a+b)
Fold: Ribosome inactivating proteins (RIP)
Superfamily: Ribosome inactivating proteins (RIP)
Occurring in:
  1. Beta-galactoside-specific lectin 1 chain A isoform 1
The deposited structure of PDB entry 1m2t contains 1 copy of SCOP domain 56372 (Plant cytotoxins) in Beta-galactoside-specific lectin 1 chain A isoform 1. Showing 1 copy in chain A.