Table 1.

Effect of streptomycin exposure on biofilm formation by M. avium strains.

M. avium Strains	No Antibiotics	Biofilm Formation (OD ± SD)^a
		Streptomycin (mg/L)^b
		0.5	1	2
104	0.236 ± 0.026	0.156 ± 0.032^*	0.534 ± 0.046^*	0.549 ± 0.041^*
101	0.243 ± 0.029	0.584 ± 0.041^*	0.563 ± 0.041^*	0.545 ± 0.065^*
A5	0.266 ± 0.041	0.668 ± 0.036^*	0.681 ± 0.044^*	0.685 ± 0.048^*
3362-33	0.222 ± 0.032	0.508 ± 0.016^*	0.628 ± 0.023^*	0.699 ± 0.037^*
3362-34	0.278 ± 0.048	0.497 ± 0.039^*	0.548 ± 0.062^*	0.591 ± 0.056^*
A5	0.286 ± 0.045	0.647 ± 0.051^c	0.670 ± 0.041^c
8G12	0.592 ± 0.051	0.732 ± 0.056^d	0.744 ± 0.026^d
5G4	0.159 ± 0.040^a	0.194 ± 0.024^d	0.211 ± 0.034^d
6H9	0.123 ± 0.067^a	0.143 ± 0.042^d	0.173 ± 0.028^d

P < 0.05 compared with biofilm without exposure to antibiotics.

Biofilm mass was measured by staining the biofilm with crystal violet and determining the optic density of the crystal violet by spectrophotometry.[5, 11]

The results are the mean of three independent experiments.

P < 0.05 compared with A5 without antibiotic exposure.

P > 0.05 compared with the mutant without exposure to antibiotic.