Fig. 5
From: Development of a counterselectable seamless mutagenesis system in lactic acid bacteria
Construction of the PheS*/pG+host9 counterselectable system in Lc. lactis NZ9000. a An effcient counterselectable system PheS*/pG+host9 used to create gene deletions in Lc. lactis NZ9000. The “pheS* cassette” indicates the pheS* gene under the control of five cascading Pldh. “up” and “down” indicate the upstream and downstream homology arms of the targeted region. “Erm” indicates the erythromycin resistant gene. “OriT” indicates the temperature sensitive origin of replication. b Twenty-four p-Cl-Phe-resistant colonies were amplified by PCR to screen for the deletion of 709 bp fragment of the galactose operon. The expected PCR fragment from the mutant type (∆) is approximately 2.0 kb, while the band from the wild-type (WT) is about 2.7 kb