Fig. 2.

Promoter orientation does not correlate with PS synthesis in B. fragilis mpi mutants due to UpxZ inhibition of heterologus PS loci transcription. (A) Schematic of the locked promoter orientations of mpiM44. PSA, PSE, and PSC promoters are locked on but the mutant expresses only PSA. (B) Western immunoblot analysis of PSA, PSE, and PSC synthesis in mpiM44, and the same mutant with successive deletions of upaZ and upeZ. (C) Northern blot analysis of PSA, PSE, and PSC transcript in mpiM44, mpiM44ΔupaZ, and mpiM44ΔupaZΔupeZ.