TABLE 4.

CT production by V. cholerae strains grown under two different cultural conditions

Strain	Amt of CTa produced in medium (ng/ml/unit of opacity)
	LBb	AKIc
O395	2,700	NDd
10259	2.8	16
10259R	2,650	53
AD48	ND	663
Co900	ND	1,035
V2	216	24
S7	1,800	80

^aAssayed by the GM1 ELISA method (17) and expressed as nanograms of toxin per milliliter of culture supernatant per unit of opacity of bacterial suspension measured at 540 nm.

^bLB medium, pH 6.5, incubation temperature of 30°C, 16 h of culture.

^cAKI medium, pH 7.8, incubation temperature of 37°C, 4 h of static culture with limited aeration followed by 16 h of mild shaking culture with adequate aeration.

^dND, not determined.