| Title |
Characterization of Hyperthermostable Fructose-1,6-Bisphosphatase from Thermococcus onnurineus NA1 |
| Author |
Yeol Gyun Lee1, Sung Gyun Kang2, Jung-Hyun Lee2, Seung Il Kim1*, and Young-Ho Chung1* |
| Address |
1Division of Life Science, Korea Basic Science Institute, Daejeon 305-806, Republic of Korea, 2Korea Ocean Research and Development Institute, Ansan 426-744, Republic of Korea |
| Bibliography |
Journal of Microbiology, 48(6),803-807, 2010,
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| DOI |
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| Key Words |
T. onnurineus NA1, thermostability, fructose-1,6-bisphosphatase, hyperthermophilic Archaea, fructose-1,6-bisphosphate |
| Abstract |
To understand the physiological functions of thermostable fructose-1,6-bisphosphatase (TNA1-Fbp) from Thermococcus onnurineus NA1, its recombinant enzyme was overexpressed in Escherichia coli, purified, and the enzymatic properties were characterized. The enzyme showed maximal activity for fructose-1,6-
bisphosphate at 95°C and pH 8.0 with a half-life (t1/2) of about 8 h. TNA1-Fbp had broad substrate specificities for fructose-1,6-bisphosphate and its analogues including fructose-1-phosphate, glucose-1-phosphate, and phosphoenolpyruvate. In addition, its enzyme activity was increased five-fold by addition of 1 mM Mg2+, while Li+ did not enhance enzymatic activity. TNA1-Fbp activity was inhibited by ATP, ADP, and phosphoenolpyruvate, but AMP up to 100 mM did not have any effect. TNA1-Fbp is currently defined as a class V fructose-1,6-bisphosphatase (FBPase) because it is very similar to FBPase of Thermococcus kodakaraensis KOD1 based on sequence homology. However, this enzyme shows a different range of substrate specificities. These results suggest that TNA1-Fbp can establish new criterion for class V FBPases. |
