. 2024 Dec 19;7:1676. doi: 10.1038/s42003-024-07336-6

Table 1.

Enzyme kinetics of 2NI hydrolysis by NnhA and its variants presented in this work, measuring nitrite release using the Greiss reaction as detailed in the methods section

NnhA variant	K_M (µM)	k_cat (min^-1)	K_cat/K_M (µm^-1 min^-1)	Notes
WT	93.1 ± 14.1	1.27 ± 0.16	0.012
T2I-G14D-K73R	109.8 ± 7.6	18.0 ± 0.42	0.164	crystallized
T2I-G14D-K73R-C352A	24.5 ± 3.3	0.73 ± 0.02	0.030
T2I-G14D-K73R-C352S	n/a	n/a	n/a	Detectable activity, but low titers of soluble enzyme
T2I-G14D-K73R-C357A	n/a	n/a	n/a	no activity, crystallized
T2I-G14D-K73R-C357S	n/a	n/a	n/a	no activity
T2I-G14D-K73R-D262N	n/a	n/a	n/a	no activity
T2I-G14D-K73R-N311D	n/a	n/a	n/a	no activity
T2I-G14D-K73R-H260N	n/a	n/a	n/a	no activity
T2I-G14D-K73R-H260F	n/a	n/a	n/a	no activity

Errors represent standard deviation calculated from n = 2 independent experiments.