Table 3 DHFR and TS activities in crude extracts and purified enzymes from TS-deficient Escherichia coli χ2913 harbouring pAC- pf DHFR and pET- pf JRTS with different lengths of JR

1. pET-pf DHFRTS (3D7)

70.3 ± 3.6

3.7 ± 0.4

5331.9 ± 113.8

99.0 ± 1.0

2. pAC-pf DHFR + pET-pf JRTSΔ232-235

39.5 ± 5.8

2.6 ± 0.2

1511.1 ± 227.5

164.1 ± 22.6

3. pAC-pf DHFR + pET-pf JRTSΔ232-251

34.2 ± 5.8

2.1 ± 0.4

1394.5 ± 275.7

134.4 ± 8.9

4. pAC-pf DHFR + pET-pf JRTSΔ232-265

37.8 ± 5.3

3.8 ± 0.5

1668.4 ± 234.7

132.0 ± 7.4

5. pAC-pf DHFR + pET-pf JRTSΔ232-271

39.9 ± 7.3

3.9 ± 0.7

1601.7 ± 206.1

107.9 ± 23.3

6. pAC-pf DHFR + pET-pf JRTSΔ232-274

38.3 ± 5.6

1.5 ± 0.3

1328.8 ± 231.7

70.1 ± 0.2

7. pAC-pf DHFR + pET-pf JRTSΔ232-276

34.2 ± 9.1

1.1 ± 0.1

1140.1 ± 137.8

44.2 ± 7.5

8. pAC-pf DHFR + pET-pf JRTSΔ232-277

31.0 ± 8.1

ND

1136.5 ± 132.0

ND

9. pAC-pf DHFR + pETpf JRTSΔ232-279

34.9 ± 7.2

ND

1193.6 ± 111.8

ND

10. pAC-28 + pET-15b

7.7 ± 0.4

ND

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