Table 5.

Effects of LiAc, heat shock and PEG on the transformation of intact cells and spheroplasts

	Intact cells	Spheroplasts
LiAc	Enhances the transformation efficiency and frequency (although not indispensable).2,38	No effect on the transformation frequency.38
	Increases the permeability of intact cells.37
Heat shock	Enhances the transformation efficiency (although not indispensable).2,15	No effect on the transformation efficiency.74
	Increases the permeability of intact cells.37
PEG	Indispensable for transformation efficiency.2,15	Not indispensable for transformation frequency but enhances the frequency.38
	Pre-incubation enhances the transformation efficiency and frequency.36
	Increases the permeability of intact cells.37
	Indispensable for DNA attachment.38	Indispensable for DNA attachment.38