Arias et al. BMC Genomics 2011, 12:390 http://www.biomedcentral.com/1471-2164/12/390 Additional file 2: Yeast mutant strains resistant to nourseothricin without increased levels of Phospho-Slt2. Functional information on the genes whose disruption leads to antibiotic resistance without detectable Slt2 phosphorylation is shown. Abbreviations CWI: cell wall integrity; MAPK: mitogen activated protein kinase; GPI: glycosylphosphatidylinositol; WT: wild-type. Acknowledgements This work was supported by projects BIO2007-67821 and BIO2010-22146 (MICINN, Spain), S-SAL-0246/2006 (CAM, Spain), GR58/08 (Ref. 920640) from UCM and Research Networking Programme (06-RNP-132; European Science Foundation). CN is head of the Merck Sharp & Dohme special chair in genomics and proteomics. Thanks are due to all members of the UCM-PCM Genomic Unit for their collaboration in managing the collection of yeast mutants and A. Vázquez of the Centro de Citometría y Microscopía de Fluorescencia (UCM, Spain) for expert help in flow cytometry. We also thank members of Research Unit 4 at the Department of Microbiology for fruitful discussions, as well as María Molina and Humberto Martin for critical reading. Plasmids bearing SLT2/MPK1 alleles were kindly provided by Dr. D. Levin (Boston University). Authors’ contributions PA was responsible for the assessment of levels of Slt2 phosphorylation, β-galactosidase assays, flow cytometry, phenotypic analysis and fluorescence microscopy. SD-M conducted the setting-up and subsequent screening for nourseothricin resistance with the collection of yeast mutants, and participated in fluorescence microscopy assays. RG carried out bioinformatic analysis and figure design. CN participated in the coordination of the study. JMR-P and JA conceived the study, participated in the design and analysis of experimental data and wrote the manuscript. 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