Table 1. Specific activities of the Bacillus subtilis bacillithiol transferases.

B. subtilis bacillithiol transferase	Specific activity with bacillithiola (nmol min-1 mg-1)	Rate of bacillithiol-mB adduct formation (pmol min-1)	Rate of cysteine-mB adduct formation (pmol min-1)	Rate of Co-mB adduct formation (pmol min-1)	Rate of bacillithiol-mB adduct formation + EDTAb (pmol min-1)
BstA (YfiT)	2.5 ± 0.4c	N/A	2.5 ± 0.2	0.3 ± 0.2	8.7 ± 0.2
BstB (YuaE)	170 ± 13	26 ± 1.1	2.5 ± 0.4	0.3 ± 0.1	8.7 ± 0.1
BstC (YisT)	49 ± 9	14 ± 1.0	2.2 ± 0.1	0.3 ± 0.2	8.9 ± 0.3
BstD (YjoA)	113 ± 6	31 ± 0.8	2.2 ± 0.4	0.3 ± 0.3	8.9 ± 0.2
BstE (YrdA)	5.8 ± 0.7	12 ± 0.9	2.4 ± 0.4	0.3 ± 0.1	8.9 ± 0.2
BstF (YkkA)	1.3 ± 0.2	10 ± 0.4	2.6 ± 0.1	0.3 ± 0.2	8.7 ± 0.1
BstG (DinB)	2.5 ± 0.3	10 ± 0.5	2.2 ± 0.3	0.3 ± 0.3	8.6 ± 0.0
BstH (YizA)	1.8 ± 0.4	10 ± 0.4	2.5 ± 0.4	0.3 ± 0.2	8.5 ± 0.2
No enzymed	-	8.7 ± 0.2	2.6 ± 0.1	0.3 ± 0.3	8.7 ± 0.1

Reactions consisted of 50 μM monochlorobimane and 50 μM thiol, and were conducted at pH = 7.0 at 23°C for a total of 20 min. For reactions with bacillithiol, the following amounts of protein: BstA: 0.1 μg, BstB: 0.1 μg, BstC: 0.1 μg, BstD: 0.2 μg, BstE: 0.5 μg, BstF: 0.8 μg, BstG: 0.5 μg, BstH: 0.8 μg. For reactions with cysteine, CoA, and bacillithiol +EDTA, 1 mg of protein was used. All values represent mean ± standard deviation (n = 3).

^aRate of chemical reaction was subtracted from the total rate to give net enzymatic rate.

^bEnzymes were incubated with 1 mM EDTA in assay buffer for 5 minutes prior to the addition of bacillithiol and monochlorobimane.

^cData from Newton et al 2011 [22].

^d“No enzyme” rate is the background chemical reaction rate of 8.7 ± 0.1 pmol min^-1.