Open AccessCharacterization of a thermophilic DNA ligase from the archaeon Thermococcus fumicolans
Author(s) -
Rolland Jeanluc,
Gueguen Yannick,
Persillon Cècile,
Masson JeanMichel,
Dietrich Jacques
Publication year - 2004
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.1574-6968.2004.tb09657.x
Subject(s) - dna ligase , thermococcus , biology , dna ligases , biochemistry , thermophile , hyperthermophile , recombinant dna , cofactor , escherichia coli , dna , nad+ kinase , microbiology and biotechnology , enzyme , archaea , gene
A PCR protocol was used to identify and sequence a gene encoding a DNA ligase from Thermococcus fumicolans ( Tfu ). The recombinant enzyme, expressed in Escherichia coli BL21(DE3) pLysS, was purified to homogeneity and characterized. The optimum temperature and pH of Tfu DNA ligase were 65 °C and 7.0, respectively. The optimum concentration of MgCl 2 , which is indispensable for the enzyme activity, was 2 mM. We showed that Tfu DNA ligase displayed nick joining and blunt‐end ligation activity using either ATP or NAD + , as a cofactor. In addition, our results would suggest that Tfu DNA ligase is likely to use the same catalytic residues with the two cofactors. The ability for DNA ligases, to use either ATP or NAD + , as a cofactor, appears to be specific of DNA ligases from Thermococcales, an order of hyperthermophilic microorganisms that belongs to the euryarchaeotal branch of the archaea domain.