TABLE 3.

Carbon and electron balances for A. caccae L1-92 and E. hallii L2-7

Parameter	No. of carbons or electronsa or mmol of substrate liter−1 consumedb				No. of carbons or electrons or mmol of product liter−1 formedb						% Recovery
	Glucose	Acetate	Lactate (d + l)	Sum	Formate	Acetate	Butyrate	H2	CO2c	Sum
No. of carbons/mol	6	2	3		1	2	4	0	1
No. of electrons/mol	24	8	12		2	8	20	2	0
L1-92 (A. caccae)
Grown on medium + dl-lactated
Δ Concn		29.8	(17.2 + 23.7)		0.1		35.6	13.0	40.9
Δ Carbon		59.6	122.7	182.3	0.1		142.4		40.9	183.3	100.5
Δ Electrons		238.4	490.8	729.2	0.2		712.4	26.0		738.4	101.3
Grown on medium + glucose
Δ Concn	10.4	2.3			2.2		11.5	8.6	18.6
Δ Carbon	62.4	6.9		69.3	2.2		46.0		18.6	66.8	96.4
Δ Electrons	249.6	18.4		268	8.8		230.0	17.2		256	95.5
L2-7 (E. hallii)
Grown on medium + dl-lactate
Δ Concn		26.1	(16.0 + 22.4)		0.4		29.6	15.5	38.4
Δ Carbon		52.2	115.2	167.4	0.4		118.4		38.4	156.8	93.7
Δ Electrons		208.8	460.8	669.6	0.8		592.0	31.0		623	93.2
Grown on medium + glucose
Δ Concn	10.2				2.0	2.7	8.0	12.0	18.4
Δ Carbon	61.2			61.2	2.0	5.4	32.0		18.4	57.8	94.4
Δ Electrons	244.8			244.8	4.0	21.6	160.0	24.0		209.6	85.6

^aReferences to electrons refer to electrons released upon formal oxidation to CO₂.

^bExperimental values are means of data from triplicate cultures after 24 h of growth. For L2-7, data are from the experiment shown in Fig. 1; standard deviations (also for the L1-92 experiment) were as indicated in the legend to Fig. 1.

^cThe value for carbon dioxide is calculated on the assumption that every 1 mol of lactate taken up (since formate production is minimal) releases 1 mol of CO₂, while 1 mol of glucose utilized releases 2 mol of CO₂ or formate: hence CO₂ is calculated as (2 × glucose) − formate.

^dYCFA medium was supplemented as shown above with either 33 mM dl-lactate or 10 mM glucose.