TABLE 1.

Transformation frequencies

Plasmid	Restricteda	Selection	Recipient strain	Frequency of transformantsb	% Stable transformantsc
pHYG7-KB1		Hygromycin	H99	20 (±16)	90
pHYG7-KB1	BamHI	Hygromycin	H99	5 (±2)	83
pHYG7-KB1		Hygromycin	JEC20	36 (±34)	2
pMH12T		G418	H99	404 (±340)	6
pMH12T	NotI	G418	H99	180 (±158)	7
pMH12T		G418	JEC20	355 (±286)	8
pMH14P		Phleomycin	H99	125 (±169)	11
pMH14P	NotI	Phleomycin	H99	70 (±89)	5
pMH14P		Phleomycin	JEC20	0 (±0)	n/a

^aThe plasmids used for transformation were either uncut or restricted with the indicated restriction enzyme. 

^bThe transformation frequencies are shown in transformants per microgram of DNA. They were determined from a minimum of six independent transformation events during at least two separate experiments. The standard deviation is shown in parenthesis. 

^cAt least 50 independent transformants were passaged three times on nonselective medium and then tested for resistance on selective medium. n/a, not applicable.