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: waiting to be named.

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 139: Pol 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
Retroviral ribonuclease H. [EC: 3.1.26.13]
Endohydrolysis of RNA in RNA/DNA hybrids. Three different cleavage modes: 1. sequence-specific internal cleavage of RNA. Human immunodeficiency virus type 1 and Moloney murine leukemia virus enzymes prefer to cleave the RNA strand one nucleotide away from the RNA-DNA junction. 2. RNA 5'-end directed cleavage 13-19 nucleotides from the RNA end. 3. DNA 3'-end directed cleavage 15-20 nucleotides away from the primer terminus.
  • Retroviral reverse transcriptase is a multifunctional enzyme responsible for viral replication.
  • To perform this task the enzyme combines two distinct activities.
  • The polymerase domain (EC 2.7.7.49) occupies the N-terminal two- thirds of the reverse transcriptase whereas the ribonuclease H domain comprises the C-terminal remaining one-third.
  • The RNase H domain of Moloney murine leukemia virus and Human immunodeficiency virus display two metal binding sites.
3 P03371 P11204 P32542
Exoribonuclease H. [EC: 3.1.13.2]
3'-end directed exonucleolytic cleavage of viral RNA-DNA hybrid.
  • This is a secondary reaction to the RNA 5'-end directed cleavage 13-19 nucleotides from the RNA end performed by EC 3.1.26.13.
3 P03371 P11204 P32542
RNA-directed DNA polymerase. [EC: 2.7.7.49]
Deoxynucleoside triphosphate + DNA(n) = diphosphate + DNA(n+1).
  • Catalyzes RNA-template-directed extension of the 3'-end of a DNA strand by one deoxynucleotide at a time.
  • Cannot initiate a chain de novo.
  • Requires a RNA or DNA primer.
  • DNA can also serve as template.
  • See also EC 2.7.7.7.
3 P03371 P11204 P32542
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