TABLE 1.

Reduction-oxidation balance during lactate metabolism with NO₃^– based on stoichiometric calculations

Process or balance	Parameters at pH 7/pH 5 under the indicated conditions
	Veillonella atypica		Veillonella parvula
	Anaerobic	Aerobic	Anaerobic	Aerobic
Oxidation (2H production [mM])
Lactate utilization (Pyr + Ace + Pro)a	0.959/1.075	0.377/0.380	0.525/0.603	0.224/0.148
Acetate production via oxidation (Ace – For)b	0.353/0.359	0.180/0.146	0.332/0.350	0.070/0.053
Reduction (2H consumption [mM])
Propionate production (Pro × 2)c	0.935/1.110	0.075/0.079	0.279/0.177	0.000/0.000
NO3– reduction (NO2–)d	0.149/0.214	0.020/0.021	0.544/0.687	0.012/0.029
Reduction-oxidation balance ([a + b]/[c + d])	1.21/1.08	5.89/5.28	1.04/1.10	24.47/6.99

^aThe amount of lactate utilized was estimated from the total amounts of pyruvate (Pyr), acetate (Ace), and propionate (Pro). One mole of 2H (reducing power) can be produced by oxidizing 1 mol of lactate to 1 mol of Pyr (Fig. 5).

^bThe amount of acetate produced via oxidation was estimated by subtracting the amount of formate (For) produced from the amount of Ace produced. One mole of 2H can be produced by oxidizing 1 mol of Pyr to 1 mol of Ace (Fig. 5).

^cTwo moles of 2H can be consumed by reducing 1 mol of Pyr to 1 mol of Pro (Fig. 5).

^dOne mole of 2H can be consumed by reducing 1 mol of NO₃^– to 1 mol of NO₂^– (Fig. 5).