​sourceforge.​net/​. Nucleic acids multiple alignments were used to obtain two phylogenies with the maximum likelihood method implemented in PHYML [35] with HKY as substitution model [36]. The phylogenetic reconstruction was carried out with

a nonparametric bootstrap analysis of 100 replicates for each alignment. TreeDyn program [37] was used to visualize and edit both phylogenies. Acknowledgements We are grateful to Laura Cervantes and Javier Rivera for their excellent technical CFTRinh-172 clinical trial assistance. We acknowledge Michael F. Dunn for critically reviewing the manuscript. This work was supported by DGAPA-PAPIIT-UNAM grant IN200309-2. Tomás Villaseñor was supported by a Ph. D. scholarship (204725) from CONACYT México during his Ph. D. studies at UNAM, Programa de Doctorado en Ciencias Biomédicas. Electronic supplementary material Additional file 1: Table S1. Rhizobial species list and accession numbers of housekeeping and panCB genes used for phylogenetic analysis. (DOC 42 KB) References 1. Jumas-Bilak E, Michaux-Charachon S, Bourg G, Ramuz M, Allardet-Servent A: Unconventional

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