TABLE 4.

Competition assays of V. cholerae ivi null mutant strains during growth in vitro and in the infant mouse small intestine

Gene product mutated	Function	Competitive indexa
		In vitro	In vivo
VC1500	Pqi family	3.9b	0.74b
VC2487	Conserved protein	0.56	0.049b
VC0488	Extracellular binding protein	1.6b	0.56
VC0622	Histidine kinase	2.2b	0.61b
VC0874	Hypothetical protein	0.95	0.045b
VC0130	GGDEF protein	1.3	0.55
VC2705	Sodium symporter	0.57	0.07b
VC2646	Phosphoenolpyruvate carboxylase	1.4b	0.67b

^aCompetitive indices were calculated as described in Materials and Methods. Each in vitro competition was done with two independent LB broth cultures, and each in vivo competition used between 8 and 10 infant mice.

^bSignificant difference from parent strain (P < 0.05) by Student's two-tailed t test using as the control group competitions between parent strain GOA1264 and GOA6W, a virulent control strain harboring a plasmid insertion in lacZ.