Figure 2

Transcriptional analysis and mbo operon promoter activity. mboA, mboC and mboE (A), belonging to the mbo operon and mgoB and mgoA (B), belonging to the mgo operon transcript levels in the wild type strain P. syringae pv. syringae UMAF0158 and mgoA and gacA mutants. (C) Comparison of the described consensus motif (5′-CANGGANG-3′) for P. fluorescens[49–51]: The search was done in front of each start codon of the mgo and mbo genes. (D) β-galactosidase activity of the mbo operon promoter in the wild-type strain UMAF0158 and mgoA, gacS and gacA mutants. These strains were transformed with the mbo operon promoter named pMP::P _mboI and the empty promoter-probe vector pMP220 was used as a control. The different mutants were also transformed with the vector pLac-mgoBCAD. Log2RQ represents the expression levels of the studied genes by relative quantification scores. Values below 0 indicates lower expression than the housekeeping gene used for normalization of data. The results are average of three independent experiments performed in triplicate. Error bars indicate standard deviation. Data were analysed for significance using an arcsine square root transformation with analysis of variance followed by Fisher’s least significant difference test (P = 0.05). Values of bars with different letter designations represent a statistically significant difference.