The name of this superfamily has been modified since the most recent official CATH+ release (v4_2_0). At the point of the last release, this superfamily was named:

"
Trypsin-like serine proteases
".

Functional Families

Overview of the Structural Clusters (SC) and Functional Families within this CATH Superfamily. Clusters with a representative structure are represented by a filled circle.
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FunFam 36740: Nonstructural polyprotein

There are 3 EC terms in this cluster

Please note: EC annotations are assigned to the full protein sequence rather than individual protein domains. Since a given protein can contain multiple domains, it is possible that some of the annotations below come from additional domains that occur in the same protein, but have been classified elsewhere in CATH.

Note: The search results have been sorted with the annotations that are found most frequently at the top of the list. The results can be filtered by typing text into the search box at the top of the table.

EC Term Annotations Evidence
Calicivirin. [EC: 3.4.22.66]
Endopeptidase with a preference for cleavage when the P1 position is occupied by Glu-|-Xaa and the P1' position is occupied by Gly-|-Yaa.
  • Viruses that are members of the Norovirus genus (Caliciviridae family) are a major cause of epidemic acute viral gastroenteritis.
  • The nonstructural proteins of these viruses are produced by proteolytic cleavage of a large precursor polyprotein, performed by a protease that is incorporated into the polyprotein.
  • Cleavage sites are apparently defined by features based on both sequence and structure since several sites in the polyprotein fulfilling the identified sequence requirements are not cleaved.
  • The presence of acidic (Asp), basic (Arg), aromatic (Tyr) or aliphatic (Leu) amino acids at the P1' position results in only minor differences in cleavage efficiency, suggesting that steric or conformational constraints may play a role in determining specificity.
  • Changes to the amino acid at the P2 position do not alter cleavage efficiency.
  • Belongs to peptidase family C37.
3 P27408 P27409 Q66914
Nucleoside-triphosphate phosphatase. [EC: 3.6.1.15]
NTP + H(2)O = NDP + phosphate.
  • The enzyme is found in eukaryotes and thermophilic bacteria, but appears to be absent from mesophilic bacteria.
  • Also hydrolyzes nucleoside diphosphates, thiamine diphosphate and FAD.
  • The enzyme from the plant Pisum sativum (garden pea) is regulated by calmodulin.
3 P27408 P27409 Q66914
RNA-directed RNA polymerase. [EC: 2.7.7.48]
Nucleoside triphosphate + RNA(n) = diphosphate + RNA(n+1).
  • Catalyzes RNA-template-directed extension of the 3'-end of an RNA strand by one nucleotide at a time.
  • Can initiate a chain de novo.
  • See also EC 2.7.7.6.
3 P27408 P27409 Q66914