Abstract
The Toxoplasma gondii genome project has revealed two putative isoforms (TgPGM-I and TgPGM-II) of α-phosphoglucomutase (EC 5.4.2.2). We obtained recombinant proteins of these isoforms from the Beverley strain of T. gondii and characterized their properties, particularly the kinetic properties of these isoforms. The specific activities of TgPGM-I and TgPGM-II for α-d-glucose 1-phosphate were 338 ± 9 and 84 ± 6 μmol/min/mg protein, respectively, at 37 °C under optimal conditions. The Kcat and Km values of TgPGM-I were 398 ± 11/s and 0.19 ± 0.03 mM and those for TgPGM-II were 93 ± 7/s and 3.53 ± 0.91 mM, respectively, for α-d-glucose 1-phosphate. Magnesium ions were the most effective divalent cations for both the enzyme activities. The maximum activities of both the enzymes were obtained in the presence of more than 0.2 mM α-d-glucose 1,6-bisphosphate. Although both enzymes were attached to the α-phosphohexomutase superfamily, amino acid sequence homology between TgPGM-I and TgPGM-II showed very low overall identity (25%). No α-phosphomannomutase (EC 5.4.2.8) activity was detected for either enzyme. The data indicated that TgPGM-I, but not TgPGM-II, may play an important role in α-d-glucose 6-phosphate production.
| Original language | English |
|---|---|
| Pages (from-to) | 206-210 |
| Number of pages | 5 |
| Journal | Parasitology International |
| Volume | 59 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 2010 Jun |
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Keywords
- α-Phosphoglucomutase
- Glycolytic pathway
- Isozyme
- Parafusin related protein 1
- Toxoplasma gondii
ASJC Scopus subject areas
- Parasitology
- Infectious Diseases
Cite this
Characterization of α-phosphoglucomutase isozymes from Toxoplasma gondii. / Imada, Mihoko; Kawashima, Shuichi; Kanehisa, Minoru; Takeuchi, Tsutomu; Asai, Takashi.
In: Parasitology International, Vol. 59, No. 2, 06.2010, p. 206-210.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Characterization of α-phosphoglucomutase isozymes from Toxoplasma gondii
AU - Imada, Mihoko
AU - Kawashima, Shuichi
AU - Kanehisa, Minoru
AU - Takeuchi, Tsutomu
AU - Asai, Takashi
PY - 2010/6
Y1 - 2010/6
N2 - The Toxoplasma gondii genome project has revealed two putative isoforms (TgPGM-I and TgPGM-II) of α-phosphoglucomutase (EC 5.4.2.2). We obtained recombinant proteins of these isoforms from the Beverley strain of T. gondii and characterized their properties, particularly the kinetic properties of these isoforms. The specific activities of TgPGM-I and TgPGM-II for α-d-glucose 1-phosphate were 338 ± 9 and 84 ± 6 μmol/min/mg protein, respectively, at 37 °C under optimal conditions. The Kcat and Km values of TgPGM-I were 398 ± 11/s and 0.19 ± 0.03 mM and those for TgPGM-II were 93 ± 7/s and 3.53 ± 0.91 mM, respectively, for α-d-glucose 1-phosphate. Magnesium ions were the most effective divalent cations for both the enzyme activities. The maximum activities of both the enzymes were obtained in the presence of more than 0.2 mM α-d-glucose 1,6-bisphosphate. Although both enzymes were attached to the α-phosphohexomutase superfamily, amino acid sequence homology between TgPGM-I and TgPGM-II showed very low overall identity (25%). No α-phosphomannomutase (EC 5.4.2.8) activity was detected for either enzyme. The data indicated that TgPGM-I, but not TgPGM-II, may play an important role in α-d-glucose 6-phosphate production.
AB - The Toxoplasma gondii genome project has revealed two putative isoforms (TgPGM-I and TgPGM-II) of α-phosphoglucomutase (EC 5.4.2.2). We obtained recombinant proteins of these isoforms from the Beverley strain of T. gondii and characterized their properties, particularly the kinetic properties of these isoforms. The specific activities of TgPGM-I and TgPGM-II for α-d-glucose 1-phosphate were 338 ± 9 and 84 ± 6 μmol/min/mg protein, respectively, at 37 °C under optimal conditions. The Kcat and Km values of TgPGM-I were 398 ± 11/s and 0.19 ± 0.03 mM and those for TgPGM-II were 93 ± 7/s and 3.53 ± 0.91 mM, respectively, for α-d-glucose 1-phosphate. Magnesium ions were the most effective divalent cations for both the enzyme activities. The maximum activities of both the enzymes were obtained in the presence of more than 0.2 mM α-d-glucose 1,6-bisphosphate. Although both enzymes were attached to the α-phosphohexomutase superfamily, amino acid sequence homology between TgPGM-I and TgPGM-II showed very low overall identity (25%). No α-phosphomannomutase (EC 5.4.2.8) activity was detected for either enzyme. The data indicated that TgPGM-I, but not TgPGM-II, may play an important role in α-d-glucose 6-phosphate production.
KW - α-Phosphoglucomutase
KW - Glycolytic pathway
KW - Isozyme
KW - Parafusin related protein 1
KW - Toxoplasma gondii
UR - http://www.scopus.com/inward/record.url?scp=77951623220&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77951623220&partnerID=8YFLogxK
U2 - 10.1016/j.parint.2010.01.007
DO - 10.1016/j.parint.2010.01.007
M3 - Article
C2 - 20153838
AN - SCOPUS:77951623220
VL - 59
SP - 206
EP - 210
JO - Parasitology International
JF - Parasitology International
SN - 1383-5769
IS - 2
ER -