Table 1.

Knock-out of rpoN

Type of experiment	Plasmids	Successes/no. of experimental trials
Integration of internal fragment	pIMK203	Recovery of electroporants: 0/6
	pIMK205	Recovery of electroporants: 0/15
Resolution of tandem duplications	pIMK208	Double recombinants: 0/100
	pIMK210	Loss of wt allele: 0/26; 0/3050
	pIMK267/268	Double recombinants: 0/39
		Loss of wt allele: 0/438
Transduction of null allele	pIMK238	0/232; 0/6216*

wt, wild type. 

*More data in Table 2.