. 2021 Jul 12;297(2):100961. doi: 10.1016/j.jbc.2021.100961

Table 1.

Specific activities and product analyses for WT 2-KPCC and dyad variants support key roles for each in specifying carboxylation reactivity

2-KPCC Enzyme	NADPH oxidation (nmol min⁻¹ mg⁻¹)^a	Acetoacetate production (nmol min⁻¹ mg⁻¹)^b	Acetone production (nmol min⁻¹ mg⁻¹)	Acetoacetate (%)
WT	517.0 (8.8)	284.5 (62)^c	ND	100
F501H	452.7 (10.6)	22.1 (0.70)^c	224 (51)^c	10
H506E	326.0 (3.3)	16.2 (3.3)	27.1 (3.2)	37
F501H_H506E	189.7 (2.8)	ND	61.6 (7.1)^c	0

Abbreviation: ND, no detectable activity.

Oxidation of NADPH was monitored as a decrease in UV–visible absorbance at 340 nm via 2-KPCC–dependent 2-KPC oxidation of NADPH (60 mM KHCO₃, 5 mM 2-KPC, and 0.25 mg 2-KPCC).

Carboxylation of 2-KPC was monitored via the rate of decrease in UV–visible absorbance at 340 nm as described by the coupled assay (2, 21).

Rates from Ref. (2).