Table 1.

Biochemical and antimicrobial activity of negamycin, tetracycline, and tigecycline on wild-type and mutant E. coli strain SQ171

Strain	NMY	TET	TIG
Wild-type	32 (2.9)	2 (15)	2 (0.28)
U1052G	256 (13)	0.5 (2.7)	2 (0.36)
U1060A	128 (11)	16 (51)	8 (2.1)

MIC measurements are in micrograms per milliliter (n = 3). IC₅₀ values (in parentheses) obtained in luminescence-based in vitro-coupled transcription–translation assays with purified components are shown in micromolar (n = 3). NMY, negamycin; TET, tetracycline; TIG, tigecycline.