Open AccessPurification and properties of Aquifex aeolicus DNA polymerase expressed in Escherichia coli
Author(s) -
Chang Jae Ryong,
Choi Jeong Jin,
Kim HyunKyu,
Kwon SukTae
Publication year - 2001
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2001.tb10735.x
Subject(s) - aquifex aeolicus , escherichia coli , exonuclease , dna polymerase , microbiology and biotechnology , klenow fragment , biology , dna , plasmid , chemistry , gene , biochemistry
The gene encoding Aquifex aeolicus ( Aae ) DNA polymerase was expressed under the control of the trp promoter on a high‐copy plasmid, pTRPNS, in Escherichia coli . The expressed enzyme was purified 11‐fold with a 13.8% yield and a specific activity of 2268.3 U mg −1 . The optimum pH of the enzyme was 6.8–7.2. The optimal concentrations of KCl and Mg 2+ were 20–30 mM and 4–5 mM, respectively. Aae DNA polymerase contained a double‐strand‐dependent 3′→5′ proofreading exonuclease activity but lacked any detectable 5′→3′ exonuclease activity.