FIG. 1.

(A) Tn917 insertion site in SA113 smc::Tn917. (B) Construction of SA113 Δsmc. The smc coding sequence, except for 1,294 bp at the 3′ end, was replaced by ermB cassette flanked with lox sites that was further removed by Cre recombinase. (C) Scheme of pCXΩsmc. The smc gene was cloned into pCX15 (31), under the transcriptional control of the xylose promoter/operator system. (D) Construction of SA113 ΔspoIIIE. The spoIIIE coding sequence, except for 68 bp at the 3′ end, was replaced by an aphAIII cassette flanked with lox sites and further removed by Cre recombinase; white arrowheads represent lox sites.