Purification and characterization of two DNA helicases from calf thymus nuclei.
نویسندگان
چکیده
منابع مشابه
Purification and Characterization of Two DNA Helicases from Calf
Two DNA helicases from calf thymus nuclei have been purified and characterized. The two proteins, designated as nuclear DNA helicase I and 11, were copurified on Bio-Rex 70, DEAE-Sepharose, phosphocellulose and subsequently separated from each other on a heparin-Sepharose column. Final purification of DNA helicase I was achieved on single-stranded DNAcellulose and that of DNA helicase I1 on ATP...
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Using a strand displacement assay we have followed DNA helicase activities during the simultaneous isolation of several enzymes from calf thymus such as DNA polymerases alpha, delta, and epsilon, proliferating cell nuclear antigen, and replication factor A. Thus we were able to discriminate and isolate four different DNA helicases called A, B, C, and D. DNA helicase A is identical with the enzy...
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The protein glutaredoxin, required for GSH-dependent ribonucleotide reduction, has been purified to homogeneity from calf thymus. The preparative method consisted of ammonium sulfate precipitation and three chromatography steps on DEAEkellulose, Sephadex G-50, and CM-Sepharose. Calf thymus glutaredoxin was assayed on the basis of its inherent GSH-disulfide transhydrogenase activity. Glutaredoxi...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1991
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(18)54950-4