A novel superfamily of nucleoside triphosphate‐binding motif containing proteins which are probably involved in duplex unwinding in DNA and RNA replication and recombination

A statistically significant similarity was demonstrated between the amino acid sequences of 4 Escherichia coli helicases and helicase subunits, a family of non‐structural proteins of eukaryotic positive‐strand RNA viruses and 2 herpesvirus proteins all of which contain an NTP‐binding sequence motif. Based on sequence analysis and secondary structure predictions, a generalized structural model for the ATP‐binding core is proposed. It is suggested that all these proteins constitute a superfamily of helicases (or helicase subunits) involved in NTP‐dependent duplex unwinding during DNA and RNA replication and recombination.