TABLE 1.

GTP/ATP ratios in B. subtilis upon antibiotic treatment^a

Condition	Mean GTP/ATP ratio	SD	SEM
No treatment	0.54	0.24	0.03
Mup70 nM	0.18	0.04	0.05
Mup70 nM Thio100 nM	1.12	0.72	0.24
Mup70 nM Tet100 μM	1.51	0.66	0.13
Mup70 nM Cam100 μM	0.55	0.35	0.12
Mup70 nM Trim100 μM	0.21	0.06	0.01

^aArtificial starvation for isoleucine induced by addition of 70 nM mupirocin was countered by the secondary antibiotic challenge. At 30 min after the addition of antibiotics, samples were collected, and the nucleotide levels were determined by HPLC. Experiments were performed with BSB1 B. subtilis wild-type strain grown at 37°C in MOPS medium supplemented with 0.4% glucose and a full set of 20 amino acids at 25 μg/ml. Mup, mupirocin; Thio, thiostrepton; Tet, tetracycline; Cam, chloramphenicol; Trim, trimethoprim.