Figure S6 Orphan cdiA-CT/cdiI modules from D. dadantii 3937 and E. coli EC869 encode functional toxin/immunity pairs. A) Purification of orphan CdiA-CT/CdiI-His6 proteins. CdiA- CTo13937/CdiIo13937-His6 and CdiA-CTo11EC869/CdiIo11EC869- His6 complexes were purified by Ni2+-affinity chromatography under non-denaturing conditions and analyzed by SDS-PAGE. B) Growth curves of E. coli DsspB cells expressing orphan CdiA-CT/ CdiI-DAS complexes. Degradation of CdiI-DAS proteins was initiated by the addition of L-arabinose to induce SspB synthesis. Control cells express SspB(D47), which does not deliver CdiI-DAS proteins to the ClpXP protease. Growth curves with square symbols represent control strains expressing SspB or SspB(D47), but not orphan CdiA-CT/CdiI-DAS complexes. (TIF) Figure S7 The CdiAI-CT of Y. pestis Microtus 91001 is related to an Rhs-CT from Waddlia chondrophila. Pairwise alignment of Y. pestis Microtus CdiA-CT91001(I) (Q74T84) and the C-terminal region of a predicted Rhs/YD-repeat protein from Waddlia chondrophila WSU 86–1044 (D6YTT8). Regions of sequence identity are shaded gray and the PxxxxDPxGL and VENN peptide motifs are boxed. (TIF) References 1. Nadell CD, Bassler BL, Levin SA (2008) Observing bacteria through the lens of social evolution. J Biol 7: 27. 2. Ng WL, Bassler BL (2009) Bacterial quorum-sensing network architectures. Annu Rev Genet 43: 197–222. 3. Lobedanz S, Sogaard-Andersen L (2003) Identification of the C-signal, a contact-dependent morphogen coordinating multiple developmental responses in Myxococcus xanthus. Genes Dev 17: 2151–2161. 4. Aoki SK, Pamma R, Hernday AD, Bickham JE, Braaten BA, et al. (2005) Contact-dependent inhibition of growth in Escherichia coli. Science 309: 1245–1248. 5. Aoki SK, Diner EJ, t’Kint de Roodenbeke C, Burgess BR, Poole SJ, et al. 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PLoS Genetics | www.plosgenetics.org 13 August 2011 | Volume 7 | Issue 8 | e1002217