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CATH Superfamily 3.30.70.3540

Nsp8 replicase, head domain

The name of this superfamily has been modified since the most recent official CATH+ release (v4_3_0). At the point of the last release, this superfamily was named:

"
Nsp8 replicase, head domain
".

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 2: ORF1a polyprotein

There are 5 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
Ubiquitinyl hydrolase 1. [EC: 3.4.19.12]
Thiol-dependent hydrolysis of ester, thioester, amide, peptide and isopeptide bonds formed by the C-terminal Gly of ubiquitin (a 76-residue protein attached to proteins as an intracellular targeting signal).
  • Links to polypeptides smaller than 60 residues are hydrolyzed more readily than those to larger polypeptides.
  • Isoforms exist with quantitatively different specificities among the best known being UCH-L1 and UCH-L3, major proteins of the brain of mammals.
  • Inhibited by ubiquitin aldehyde (in which Gly76 is replaced by aminoacetaldehyde).
  • Belongs to peptidase family C12.
 5 K9N638 K9N638 K9N7C7 M1RUQ1 M1RUQ1
SARS coronavirus main proteinase. [EC: 3.4.22.69]
TSAVLQ-|-SGFRK-NH(2) and SGVTFQ-|-GKFKK the two peptides corresponding to the two self-cleavage sites of the SARS 3C-like proteinase are the two most reactive peptide substrates. The enzyme exhibits a strong preference for substrates containing Gln at P1 position and Leu at P2 position.
  • SARS coronavirus main protease is the key enzyme in SARS coronavirus replicase polyprotein processing.
  • Belongs to peptidase family C30.
 5 K9N638 K9N638 K9N7C7 M1RUQ1 M1RUQ1
RNA helicase. [EC: 3.6.4.13]
ATP + H(2)O = ADP + phosphate.
  • RNA helicases utilize the energy from ATP hydrolysis to unwind RNA.
  • Some of them unwind RNA with a 3' to 5' polarity, other show 5' to 3' polarity.
  • Some helicases unwind DNA as well as RNA.
  • May be identical with EC 3.6.4.12 (DNA helicase).
 1 K9N7C7
DNA helicase. [EC: 3.6.4.12]
ATP + H(2)O = ADP + phosphate.
  • DNA helicases utilize the energy from ATP hydrolysis to unwind double-stranded DNA.
  • Some of them unwind duplex DNA with a 3' to 5' polarity (1,3,5,8), other show 5' to 3' polarity (10,11,12,13) or unwind DNA in both directions (14,15).
  • Some helicases unwind DNA as well as RNA (4,9).
  • May be identical with EC 3.6.4.13 (RNA helicase).
 1 K9N7C7
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.
 1 K9N7C7