Table 2.

CO binding constants for Ns H-NOX and selected H-NOX proteins

ProteinCO kon, × 106 M-1 s-1CO koff, s-1CO KD*, μMRef.
Laser photolysisStopped flow
Ns H-NOX
Wild-type3.7 ± 0.11.52 ± 0.016.73 ± 0.424.42 ± 0.28
L67W4.4 ± 0.22.42 ± 0.046.71 ± 0.152.78 ± 0.08
L66W5.1 ± 0.32.84 ± 0.127.36 ± 0.622.59 ± 0.24
L66W/L67WN/D§2.74 ± 0.135.36 ± 0.201.96 ± 0.12
T48W5.0 ± 0.22.49 ± 0.074.13 ± 0.541.66 ± 0.22
I9W4.3 ± 0.32.12 ± 0.077.00 ± 0.183.30 ± 0.14
Tt H-NOX4.1 ± 0.22.18 ± 0.093.56 ± 0.421.63 ± 0.20
sGCN/D0.0358 ± 0.00153.5 ± 0.5 98 ± 15 54
  • *Calculated from koff/kon using stopped-flow data.

  • This work unless otherwise noted.

  • Error (±) represents the standard deviation.

  • §N/D, not determined.