Table 1 Initial rates of L-aspartate uptake by GltTk reconstituted in proteoliposomes. In the first column, the concentrations in parentheses indicate the amount of choline chloride used in the external reaction buffer to balance the osmotic and ionic strength. Each uptake rate represents the average of three independent biological replicates and independent reconstitutions, each with two technical replicates. The standard error of the mean is indicated.

From: Kinetic mechanism of Na+-coupled aspartate transport catalyzed by GltTk

[L-Asp]→ [Na+↓]

0.05 µM

0.1 µM

0.5 µM

1 µM

5 µM

10 µM

50 µM

100 µM

1 mM

(299 mM)

Not determined

Not determined

Not determined

0.03

± 2.6 10āˆ’2 mināˆ’1

0.51

± 0.3 mināˆ’1

0.25

± 0.3 mināˆ’1

2.85

± 1.2 mināˆ’1

10.93

± 4.4 mināˆ’1

5 mM

(295 mM)

0.05

± 1.6 10āˆ’2 mināˆ’1

0.06

± 2.1 10āˆ’2 mināˆ’1

0.59

± 0.1 mināˆ’1

0.96

± 0.2 mināˆ’1

3.62

± 0.7 mināˆ’1

6.48

± 0.9 mināˆ’1

16.59

± 2.8 mināˆ’1

21.62

± 3.2 mināˆ’1

10 mM

(290 mM)

0.21

± 5.5 10āˆ’2 mināˆ’1

0.28

± 0.1 mināˆ’1

2.16

± 0.4 mināˆ’1

3.75

± 0.6 mināˆ’1

8.19

± 1.2 mināˆ’1

12.60

± 1.9 mināˆ’1

25.08

± 5.0 mināˆ’1

30.51

± 4.1 mināˆ’1

25 mM

(275 mM)

0.95

± 0.2 mināˆ’1

1.46

± 0.5 mināˆ’1

8.53

± 1.2 mināˆ’1

11.56

± 1.7 mināˆ’1

19.09

± 2.0 mināˆ’1

26.39

± 3.0 mināˆ’1

40.58

± 6.4 mināˆ’1

43.59

± 6.9 mināˆ’1

50 mM

(250 mM)

1.88

± 0.4 mināˆ’1

3.34

± 1.0 mināˆ’1

16.79

± 2.6 mināˆ’1

21.26

± 2.3 mināˆ’1

31.28

± 3.5 mināˆ’1

39.30

± 4.9 mināˆ’1

43.69

± 8.3 mināˆ’1

50.21

± 4.4 mināˆ’1

100 mM

(200 mM)

2.75

± 0.5 mināˆ’1

4.79

± 1.5 mināˆ’1

23.46

± 2.5 mināˆ’1

30.47

± 3.3 mināˆ’1

38.90

± 3.5 mināˆ’1

52.16

± 7.7 mināˆ’1

53.52

± 7.9 mināˆ’1

68.13

± 3.5 mināˆ’1

200 mM

(100 mM)

3.06

± 0.6 mināˆ’1

4.83

± 1.5 mināˆ’1

31.27

± 6.4 mināˆ’1

32.55

± 3.8 mināˆ’1

37.29

± 4.0 mināˆ’1

49.80

± 9.0 mināˆ’1

51.90

± 6.7 mināˆ’1

65.40

± 7.5 mināˆ’1

300 mM

(0 mM)

2.93

± 0.7 mināˆ’1

4.96

± 1.6 mināˆ’1

27.72

± 5.3 mināˆ’1

28.95

± 4.0 mināˆ’1

40.12

± 5.4 mināˆ’1

46.98

± 7.9 mināˆ’1

52.69

± 8.5 mināˆ’1

61.77

± 2.9 mināˆ’1