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A rapid procedure to purify Escherichia coli DNA topoisomerase I.

ABSTRACT: On the basis of the asymmetrical charge distribution of Escherichia coli DNA topoisomerase I, we developed a new procedure to purify E. coli DNA topoisomerase I in the milligram range. The new procedure includes using both cation- and anion-exchange columns, i.e., SP-Sepharose FF and Q-Sepharose FF columns. The E. coli DNA topoisomerase I purified here is free of DNase contamination. The kinetic constants of the DNA relaxation reaction of E. coli DNA topoisomerase I were also determined.

SUBMITTER: Xu X

PROVIDER: S-EPMC3070380 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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A rapid procedure to purify Escherichia coli DNA topoisomerase I.

Xu Xiaozhou X Leng Fenfei F

Protein expression and purification 20110215 2

On the basis of the asymmetrical charge distribution of Escherichia coli DNA topoisomerase I, we developed a new procedure to purify E. coli DNA topoisomerase I in the milligram range. The new procedure includes using both cation- and anion-exchange columns, i.e., SP-Sepharose FF and Q-Sepharose FF columns. The E. coli DNA topoisomerase I purified here is free of DNase contamination. The kinetic constants of the DNA relaxation reaction of E. coli DNA topoisomerase I were also determined. ...[more]

PMID: 21310243

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