Skip to main content
. Author manuscript; available in PMC: 2020 Feb 1.
Published in final edited form as: J Mol Biol. 2018 Dec 21;431(3):576–592. doi: 10.1016/j.jmb.2018.12.010

Table 2. Kinetic parameters for ZmALDH12 active-site mutant variants.

Saturation curves for substrates GSAL and GRSAL were measured in 100 mM pyrophosphate buffer (pH 7.5) containing 3.0 mM NAD+. Kinetic constants Km and kcat including their standard error values were determined using GraphPad Prism 5.0 software. n.d.- not determined, *only specific activity measured with 1 mM substrate.

Enzyme Km
(μM)		 kcat
(s−1)		 kcat/Km
(s−1M−1)		 Km
(μM)		 kcat
(s−1)		 kcat/Km
(s−1M−1)
GSAL  GRSAL
ZmALDH12 198 ± 21 6.76 ± 0.47 3.4 ± 0.6 × 104  84 ± 5  1.91 ± 0.21 2.3 ± 0.4 × 104
F202A 969 ± 45 0.15 ± 0.01 1.5 ± 0.1 × 102  480 ± 28  0.21 ± 0.01 4.4 ± 0.4 × 102
E205A 120 ± 5 0.21 ± 0.01 1.8 ± 0.1 × 103  32 ± 4  0.53 ± 0.02 1.6 ± 0.3 × 104
C330A n.d. 6.8 ± 0.9 × 10−4* n.d.  n.d. 1.7 ± 0.3 × 10−4* n.d.
S331A 624 ± 27 1.83 ± 0.04 2.8 ± 0.2 × 103  227 ± 16  0.89 ± 0.03 3.9 ± 0.4 × 103
K329A 958 ± 47 0.26 ± 0.01 2.7 ± 0.2 × 102  442 ± 70  0.31 ± 0.04 7.0 ± 1.9 × 102
F505A 170 ± 18 0.03 ± 0.001 1.9 ± 0.3 × 102  379 ± 41  0.52 ± 0.04 1.4 ± 0.3 × 103