Table 3.

Antibacterial activity of glycosylamines

Compounds	MIC (µg/ml)
	E.coli GR 501+ pTrc99A	E.coli GR 501+ Mtu NAD+ligase	E.coli GR 501+ T4 DNA ligase	S.typhimurium LT2	S.typhimurium TT15151
1	0.2	12	54	10.5	52
4	0.1	18	76	20	80

The MIC values were determined by broth microdilution for the bacterial strains E.coli GR501 and S.typhimurium LT2 (which contains its NAD⁺ ligase) and the DNA ligase-minus (null) derivative TT15151 (lig-2::Mu dJ/pBR313/598/8/1b [T4Lig⁺] AMPr) (35) rescued with T4Lig⁺ plasmid. E.coli GR501 ligA^ts is a strain containing a temperature-sensitive ligase mutant (34); a defect that is restored by the overexpression of MtuLigA (13,38) or T4Lig (34). Polymyxin B nonapeptide (20 µg/ml) was added to the growth medium to facilitate passage of the inhibitors across the outer membrane of the cell.