We are very indebted to Birgit Baumgarth, Computational Genomics, Center for Biotechnology

(CeBiTec), Bielefeld University for performing later hybridisation experiments and support in data processing. We also would like to thank Anne Pohlmann for the excellent assistance in the real-time experiments. Electronic supplementary material Additional file 1: Table S1. The genes of FZB42 with known function whose transcriptions were significantly altered in response to maize root exudates at OD3.0 (Refer to experiment “Response to RE”: E-MEXP-3421). Table S2: The genes of FZB42 with putative function or encoding hypothetical protein whose transcriptions were significantly altered in response to maize root exudates at OD3.0 (Refer to experiment “Response to RE”: E-MEXP-3421). Table S3: The genes of FZB42 LDE225 chemical structure with unknown function whose transcriptions were significantly altered in response to

maize root exudates at OD3.0 (Refer to experiment “Response to RE”: E-MEXP-3421). Table S4: The primers used for real-time PCR. (DOCX 52 kb) (DOCX 52 KB) Additional file 2: Table S5. Differentially expressed genes of FZB42 in response to IE compared with those to RE (Refer to experiment “IE <> RE”: E-MEXP-3553). The genes highlighted were those with a q value of ≤0.01. (DOC 33 kb) (DOC 34 KB) Additional file 3: Table S6. Microarray experimental design and data bank accession. (DOC 40 kb) (DOC PS-341 concentration 40 KB) Additional file 4: Figure S2. Growth of FZB42 at 24°C under continuous shaking (220 rpm/min.) in medium 1 C supplemented with sterilized 10% soil extract prepared by extracting of 500 g (dry weight) compost soil with 1 L distilled water. Cells were sampled during exponential growth (OD600 = 1.0) and during transition to stationary growth phase. The time of sampling in the transition phase (O.D.600 = 3.0) is indicated by the red arrow. (DOC 32 kb) (DOC 32 KB) References

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