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Comparisons between the structures of HCV and Rep helicases reveal structural similarities between SF1 and SF2 super-families of helicases.

ABSTRACT: Three helicase structures have been determined recently: that of the DNA helicase PcrA, that of the hepatitis C virus RNA helicase, and that of the Escherichia coli DNA helicase Rep. PcrA and Rep belong to the same super-family of helicases (SF1) and are structurally very similar. In contrast, the HCV helicase belongs to a different super-family of helicases, SF2, and shows little sequence homology with the PcrA/Rep helicases. Yet, the HCV helicase is structurally similar to Rep/PcrA, suggesting preservation of structural scaffolds and relationships between helicase motifs across these two super-families. The comparison study presented here also reveals the existence of a new helicase motif in the SF1 family of helicases.

SUBMITTER: Korolev S

PROVIDER: S-EPMC2143965 | biostudies-other | 1998 Mar

REPOSITORIES: biostudies-other

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Comparisons between the structures of HCV and Rep helicases reveal structural similarities between SF1 and SF2 super-families of helicases.

Korolev S S Yao N N Lohman T M TM Weber P C PC Waksman G G

Protein science : a publication of the Protein Society 19980301 3

Three helicase structures have been determined recently: that of the DNA helicase PcrA, that of the hepatitis C virus RNA helicase, and that of the Escherichia coli DNA helicase Rep. PcrA and Rep belong to the same super-family of helicases (SF1) and are structurally very similar. In contrast, the HCV helicase belongs to a different super-family of helicases, SF2, and shows little sequence homology with the PcrA/Rep helicases. Yet, the HCV helicase is structurally similar to Rep/PcrA, suggesting ...[more]

PMID: 9541392

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