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Table 1 Kinetic constants for oxidation of five substrates (at fixed pH for each substrate) by C. subvermispora MnP6 and its S168W and S168W-environment variants compared with P. chrysosporium LiP-H8 and P. ostreatus VP1

From: Engineering a fungal peroxidase that degrades lignin at very acidic pH

   MnP6 S168W S168W-environment LiP-H8 VP1
Mn2+ K m (μM) 8.7 ± 1.6 8.5 ± 1.2 11.0 ± 1.8 - 98.0 ± 5.6
kcat (s-1) 83.0 ± 5.0 60.5 ± 5.0 66.9 ± 6.0 0 185.0 ± 2.6
kcat/K m (s-1.mM-1) 9540 ± 650 7110 ± 650 6060 ± 650 0 1900 ± 90
VA K m (μM) 0 2740 ± 560 21600 ± 200 190 ± 17 5500 ± 46
kcat (s-1) 0 0.54 ± 0.04 1.69 ± 0.04 17.5 ± 0.5 12.7 ± 0.5
kcat/K m (s-1. mM-1) - 0.197 ± 0 0.078 ± 0 92.0 ± 6.0 2.3 ± 0.2
RB5 K m (μM) 0 12.6 ± 3 5.4 ± 3 0 5.4 ± 0.2
kcat (s-1) 0 7.8 ± 1.1 7.0 ± 1.1 0 12.9 ± 0.3
kcat/K m (s-1. mM-1) - 619 ± 27 1310 ± 100 - 2380 ± 50
ABTS K m (μM) 0 60.2 ± 13.4 0 23.0 ± 1.6 4.0 ± 0.4
kcat (s-1) 0 1.4 ± 0.1 0 13.0 ± 0.2 14.4 ± 0.4
kcat/K m (s-1. mM-1) - 23 ± 3 - 563 ± 36 3600 ± 20
DMP K m (μM) 0 0 0 5.8 ± 0.5 54 ± 4
kcat (s-1) 0 0 0 10.0 ± 0.1 6.6 ± 0.1
kcat/K m (s-1. mM-1) - - - 1720 ± 153 122 ± 7
  1. Means and 95% confidence limits from triplicate reactions of the C. subvermispora MnP6 (JGI genome model 50686), its S168W and S168W-environment variants (the latter combining T162S, S168W, F258E, F262M, F268K, Q271N, S272R, and S275G mutations), P. ostreatus VP1 (JGI genome model 137757), and P. chrysosporium LiP-H8 (JGI genome model 131707) at 25°C in 0.1 M tartrate, pH 5.0 for Mn2+, pH 3.0 for VA, and pH 3.5 for RB5, DMP, and ABTS oxidation. ABTS and DMP oxidation by VP1 shows biphasic kinetics enabling calculation of a second low-efficiency set of constants (not shown).