Asparagine proteases

Asparagine proteases in viruses plays a role in capsid maturation. They are a type of enzyme that catalyze the cleavage of peptide bonds without hydrolysis and use a asparagine residue in their active site. (Wikipedia)

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Enzymatic reaction: Enzymatic reaction:

  • Asn-endopeptidase

Mechanism
The active site consists of an asparagine and at least one acidic amino acid (Asp, Glu). The terminal asparagine azote acts as a nucleophile and attacks the carbonyl atom of the peptide bond, forming a succimide residue and cleaving the peptide bond; the acidic amino acid assists the process by stabilizing the reaction intermediates.

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Viral molecular biology Virus entry
Transcription and replication
Virus exit
Replication cycles
Virion
Enzymes
Protein processing
Enterovirus 71 procapsid protein (Clan NE)

GenomeOrderFamilyFunctionTypeMEROPS familyDistribution (low incidence)Clan (fold)InterproUniProt exemplar
dsRNA Nodamuvirales imageimage Nodaviridae Self-cleavage, Virion maturation Asparagine (Asn/Ala) Peptidase N1 Virus NA
 IPR000696 Capsid protein precursor
ssRNA+ Hepevirales image Alphatetraviridae Self-cleavage, Virion maturation Asparagine (Asn/?) Peptidase N2 Virus NA
 IPR005313 Capsid protein precursor
ssRNA+ Durnavirales Picobirnaviridae Self-cleavage, Virion maturation Asparagine Peptidase N5 Virus NE
 Capsid protein precursor
dsRNA Reovirales imageimage Spinareoviridae, Orthoreovirus, Aquareovirus Self-cleavage, Virion maturation Asparagine Peptidase N7 Virus NC
 IPR009113 Outer capsid protein mu-1
ssRNA+ Picornavirales imageimage Picornaviridae, Enterovirus Self-cleavage, Virion maturation Asparagine Peptidase N8 Virus NA
 IPR029053 Polyprotein
ssRNA+ Imitervirales imageMimiviridae Self-cleavage, Intein Asparagine Peptidase N10 Animal, plant, protozoa, bacteria, archaea, virus PD
 IPR006141 DNA polymerase
ssRNA+ Algavirales imagePhycodnaviridae Self-cleavage, Intein Asparagine Peptidase N10 Animal, plant, protozoa, bacteria, archaea, virus PD
 IPR006141 DNA polymerase