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Updated: Aug 8, 2026

Measuring In Vitro ATPase Activity for Enzymatic Characterization
Published on: August 23, 2016
Characterization of ATPase activity of recombinant human Pif1
Yu Huang1, Deng-Hong Zhang, Jin-Qiu Zhou
1Max-Planck Junior Research Group at the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
Abstract:
Saccharomyces cerevisiae Pif1p helicase is the founding member of the Pif1 subfamily that is conserved from yeast to human. The potential human homolog of the yeast PIF1 gene has been cloned from the cDNA library of the Hek293 cell line. Here, we described a purification procedure of glutathione S-transferase (GST)-fused N terminal truncated human Pif1 protein (hPif1deltaN) from yeast and characterized the enzymatic kinetics of its ATP hydrolysis activity. The ATPase activity of human Pif1 is dependent on divalent cation, such as Mg2+, Ca2+ and single-stranded DNA. Km for ATP for the ATPase activity is approximately 200 microM. As the ATPase activity is essential for hPif1's helicase activity, these results will facilitate the further investigation on hPif1.
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