Table 3.

Effect of plasmid DNA concentration on transformation frequency.

DNA quantity	Average transformation frequency (transformants/CFU) [SE]
10 μg	5.6 × 10-3 [1.1 × 10-3]
5 μg	5.0 × 10-3 [1.4 × 10-3]
2 μg	3.3 × 10-4 [9.6 × 10-5]
1 μg	2.5 × 10-4 [3.7 × 10-5]
0 μg	0

The effect of plasmid DNA concentration of transformation frequency was examined by transforming M. hyopneumoniae strain 232 with different quantities of pMHO-2 DNA. Average transformation frequencies (with standard error) of three transformations are shown.