Table 2 Kinetics of ATPase and drug transport activities of M2-Del903 and M2-Del905.

From: Newly identified motifs in Candida albicans Cdr1 protein nucleotide binding domains are pleiotropic drug resistance subfamily-specific and functionally asymmetric

Transport and Kinetics Parameters

Cdr1p

M2-Del903

M2-Del905

ATP kinetics

ATPase activity (nmoles/mg/min)

78 ± 14

27.1 ± 4.4

55 ± 11

Km (mM)

2.1 ± 0.5

6.7 ± 0.8

2.9 ± 0.8

Vmax (nmoles/mg/min)

105 ± 15

45.3 ± 9.1

99.2 ± 8.9

Drug transport kinetics

R6G efflux (nmoles/108cells)

4.3 ± 0.6

1.2 ± 0.5

1.2 ± 0.2

R6G binding KdR6G (μM)

9.0 ± 1.8

11.9 ± 1.9

25 ± 2.0

R6G efflux rate (nmoles/108cells/min)

4.3 ± 0.4

2.1 ± 0.3

2.6 ± 0.4

  1. The values are the means ± standard deviation of three independent experiments. Km and Vmax values were calculated using Lineweaver-Burke plots. Differences greater than 2-fold compared with Cdr1p were considered significant (underlined).
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