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Review
. 2002 Apr;184(7):1819-26.
doi: 10.1128/JB.184.7.1819-1826.2002.

Modularity and specialization in superfamily 1 and 2 helicases

Martin R Singleton  1 , Dale B Wigley
Affiliations
Review

Modularity and specialization in superfamily 1 and 2 helicases

Martin R Singleton et al. J Bacteriol. 2002 Apr.
No abstract available

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Figures

FIG. 1.
FIG. 1.
Ribbon diagram of the PcrA apoenzyme. The RecA-like domains (1A/2A) are light grey, and the 1B/2B domains are dark grey. The colors of the seven helicase motifs are as follows: motif I, magenta; motif Ia, blue; motif II, orange; motif III, green; motif IV, cyan; motif V, yellow; motif VI, red. This and the subsequent figures were created with the RIBBONS program (5).
FIG. 2.
FIG. 2.
Ribbon diagrams of the SF1 and SF2 helicases. The RecA-like domains are in blue (equivalent to PcrA domain 1A) and red (equivalent to PcrA domain 2A). The structures are as follows: A, PcrA from B. stearothermophilus; B, Rep helicase from E. coli; C, NS3 protein helicase domain from hepatitis C virus; D, eIF4A-type RNA helicase from M. jannaschii; E, UvrB from Thermus thermophilus; F, RecG from Thermotoga maritima.
FIG. 3.
FIG. 3.
Depiction of the manner of substrate binding in an SF1 (PcrA, panel A) and an SF2 (NS3 protein, panel B) helicase. The bound oligonucleotide is cyan, and the amino acid side chains involved in binding are purple. In the NS3 structure, the hydrophobic side chains that bookend the substrate are yellow.
See this image and copyright information in PMC

References

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    1. Ariyoshi, M., T. Nishino, H. Iwasaki, H. Shinagawa, and K. Morikawa. 2000. Crystal structure of the Holliday junction DNA in complex with a single RuvA tetramer. Proc. Natl. Acad. Sci. USA 97:8257-8262. - PMC - PubMed
    1. Bird, L. E., H. S. Subramanya, and D. B. Wigley. 1998. Helicases: a unifying structural theme? Curr. Opin. Struct. Biol. 8:14-18. - PubMed
    1. Bird, L. E., J. A. Brannigan, H. S. Subramanya, and D. B. Wigley. 1998. Characterisation of Bacillus stearothermophilus PcrA helicase: evidence against an active rolling model. Nucleic Acids Res. 26:2686-2693. - PMC - PubMed
    1. Carson, M. 1991. Ribbons 2.0. J. Appl. Crystallogr. 24:958-961.

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