TABLE 2.

Isolation of trxA deletion mutations in the presence of complementing plasmids^a

Plasmid	No. (%) of trxA deletions observed/total no. tested
None	0/468
ptrxA	27/84 (32)
ptrxC	0/23
ptrxD	0/20
ptrxE	0/51
ptrxF	0/47
ptrxG	0/72

^aStrain IB473 containing the trxA deletion construct single crossover integrated into the trxA gene was the recipient for all trx-containing plasmids. Deletions were identified by PCR analysis of the genomic DNA isolated from individual colonies that had resolved the trxA deletion construct (see Materials and Methods for more details).