Table 2.

Thiol levels in wild-type M. smegmatis mc²155 and mshA mutants

Strain or genotype and growth phasea	Mean level ± SD (μmol/g [dry wt], n = 3)
	MSH	Cysteine	Coenzyme A	Lipoic acidb	Lipoamideb	Ergothioneine
mc2155
Exponential	8.8 ± 0.2	0.080 ± 0.005	1.8 ± 0.1	<0.001	<0.001	0.053 ± 0.01
Stationary	2.4 ± 0.3	0.043 ± 0.004	1.2 ± 0.1	ND	ND	0.11 ± 0.002
mshA::Tn5
Exponential	<0.003	0.082 ± 0.004	1.4 ± 0.1	<0.001	<0.001	1.4 ± 0.1
Stationary	<0.003	0.027 ± 0.001	1.0 ± 0.3	ND	ND	0.52 ± 0.02
mshA(G32D)
Exponential	<0.003	0.095 ± 0.004	1.8 ± 0.2	<0.003	<0.003	1.85 ± 0.020
Stationary	<0.003	0.057 ± 0.007	1.2 ± 0.2	ND	ND	0.85 ± 0.06

^aIn the exponential phase, growth was at 37°C in liquid Middlebrook 7H9 medium, 1% glucose, 0.05% Tween 80 for 16 h (A₆₀₀ ∼ 1). In the stationary phase, growth was as for exponential growth but for 48 h (A₆₀₀ > 2.5).

^bUnbound forms. ND, not determined.