TABLE 2.

Phenotypes of nicotinamide biosynthesis and recycling mutants

Summary of the differences in phenotypes observed with the Mtb mutants used in this study. ND, not done.

	WT	nad::hyg	pncB1::aph	pncB1::aph pncB2::hyg
[14C]Nicotinamide incorporation	+	+	+	-
[14C]Nicotinic acid incorporation	+	+	+	-
Survival (nicotinamide starvation)	+	-	+	+
Total NAD(H) in nmol/mg	1.03 ± 0.18	0.18 ± 0.0.03a	0.86 ± 0.12	0.93 ± 0.22
Fold increase in vivo/in vitrob	100-1000×	ND	100-1000×	ND
Phenotype in vivoc	3.1 × 105	6 × 103	2.0 × 105	1.3 × 105

^aTotal NAD(H) after 4 days of nicotinamide starvation.

^bRatio of [¹⁴C]nicotinamide incorporated in vivo/in vitro.

^cColony-forming units of Mtb found in mouse lungs 112 days after aerosol infection.