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Nucleic Acids Res. 1997 July 1; 25(13): 2620–2626.
PMCID: PMC146783

Characterization and crystallization of the helicase domain of bacteriophage T7 gene 4 protein.


Limited proteolysis of bacteriophage T7 primase/helicase with endoproteinase Glu-C produces several proteolytic fragments. One of these fragments, which is derived from the C-terminal region of the protein, was prepared and shown to retain helicase activity. This result supports a model in which the gene 4 proteins consist of functionally separable domains. Crystals of this C-terminal fragment of the protein have been obtained that are suitable for X-ray diffraction studies.

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Selected References

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