TABLE 2.

Amount of substrate MS-mB and product AcCyS-mB of Mca present intracellularly and extracellularly in the parent strain and the mca mutant Ami37 following reaction with mBBr

Substrate	Amt of substrate for strain:
	mc2155	Ami37
Intracellular
MS-mB (μmol/g)	2.8 ± 0.02	16.6 ± 0.5
AcCyS-mB (μmol/g)	9.9 ± 0.2	<0.02
Total	12.7	16.6 ± 0.5
Extracellular
AcCyS-mB (μM)	0.75 ± 0.04	<0.1