TABLE 2.

Glucose uptake capacity at a glucose concentration of 50 mM (9 g/liter) after carbon or nitrogen starvation of cells grown in a chemostat,^e with a statistical analysis using Student's two-sample t test performed^f

Growth condition (pH)	Acid present	Glucose uptake capacity (μmol/g protein/min)
		C starved	N starved
Carbon limited (5)	0a	NDd	NDd
	L90b	180 ± 4	200 ± 3
	L280b	120 ± 20	99 ± 12
	B5c	140 ± 4	98 ± 28
Carbon limited (3.25)	0a	96 ± 31	130 ± 0
	L90b	20 ± 2	95 ± 28
	L280b	25 ± 2	92 ± 15
Nitrogen limited (5)	0a	120 ± 46	150 ± 58
	L90b	290 ± 112	200 ± 13
	L280b	99 ± 64	150 ± 3
	B5c	340 ± 60	210 ± 71
Nitrogen limited (3.25)	0a	170 ± 92	190 ± 12
	L90b	77 ± 4	170 ± 7
	L280b	18 ± 6	88 ± 8

^aNo weak acid present.

^bLactic acid present at a concentration of 90 or 280 mM.

^cBenzoic acid present at a concentration of 5 mM.

^dND, not determined.

^eStandard deviations were calculated from two separate starvation conditions.

^fStudent's two-sample t test (P > 0.01; df = 4 or 5) was used for a statistical analysis of the data. The group of values obtained from cells grown under carbon limitation at pH 5 and starved for carbon or nitrogen, respectively, was used as a reference when comparing with similarly starved cells grown at carbon limitation at pH 3.25, nitrogen limitation at pH 5, or at nitrogen limitation at pH 3.25, respectively. The P value was never < 0.01, indicating that there were no statistically significant differences between the groups. A comparison between carbon- and nitrogen-starved cells grown under the same growth conditions was also performed and always resulted in a P value of >0.01.