TABLE 2.

Susceptibility of Y. enterocolitica strains to chloramphenicol and polymyxin B.

Antibiotics	Strains	Average clearing zone (mm)
		0.0625 mg/ml	0.125 mg/ml	0.25 mg/ml	0.5 mg/ml	1 mg/ml	2 mg/ml
Chloramphenicol	WT	−	6.88 ± 0.16	10.20 ± 0.12	13.52 ± 0.10	19.76 ± 0.11	21.48 ± 0.15
	△opgGH	−	7.40 ± 0.27	11.04 ± 0.07	14.18 ± 0.29	20.28 ± 0.11	21.81 ± 0.17
	△opgGH- PBADopgGH	−	−	7.55 ± 0.31	10.45 ± 0.31	17.54 ± 0.38	20.47 ± 0.35
Polymyxin B	WT	−	−	1.69 ± 0.10	2.93 ± 0.06	4.68 ± 0.24	5.14 ± 0.17
	△opgGH	−	−	2.07 ± 0.04	3.34 ± 0.06	5.00 ± 0.11	5.45 ± 0.10
	△opgGH- PBADopgGH	−	−	−	1.50 ± 0.09	2.71 ± 0.06	3.78 ± 0.05

The data are presented as the mean ± SD of at least three separate experiments. “−”, not detected.