On the other hand, strain RAY3A  had a susceptibility to peptide MK0683 killing similar to strains FY1679 and BY4741. Figure 1 Antifungal activity of peptides PAF26 and melittin to S. cerevisiae FY1679. (A) Dose response curve of cell killing activity. Cells were exposed to different concentrations of peptides for 24 h. Cell survival (measured as CFU/mL) was determined by dilution
and plating. (B) Time course of cell population growth was followed in the presence of 5 μM of peptide. No significant differences were found between each of the peptides and the control treatment. In both (A) and (B) panels, grey circles and white triangles indicate PAF26 and melittin samples, respectively; in (B), white squares show controls in the absence of peptide. Global transcriptome response of S. cerevisiae to PAF26 and melittin In order MX69 nmr to gain knowledge and compare the antifungal effect of PAF26 and melittin we carried out the characterization of the transcriptome of S. cerevisiae after exposure to these peptides. The global transcriptome response to peptides was undertaken by treating S. cerevisiae FY1679 cells in the logarithmic growth phase to sub-lethal concentrations (5 μM) of either PAF26 or melittin for 3 hours. Under these assay conditions, no significant 4SC-202 mouse effects on growth were observed for any of the two peptides even after
up to 24 hours of treatment (Figure 1B). DNA macroarrays representing more than 6,000 yeast genes were hybridized with the cDNAs from treated cells. The complete data set containing the quantification of signals has been submitted to the GEO public database http://www.ncbi.nlm.nih.gov/geo/. Annotation, processing and statistical significance of expression change for each DNA probe are shown in Additional File 2. Subsequent data analysis allowed the identification of genes with differential expression after each peptide treatment, as compared with control sample in the absence of peptide. In total, 385 genes (7.4%) of the 5,174 analyzed genes were responsive to melittin
treatment while 355 genes (6.8%) of the 5,230 analyzed were differentially expressed after PAF26 treatment. Additional File Inositol monophosphatase 1 3 shows additional information on the genes with higher induction or repression upon each treatment. Some examples of the most differential genes are ARG1 as the gene with the highest induction specific of PAF26, PSO2 having the highest co-induction with both peptides, or STE5 and BTN2 as the most repressed with both peptides. Figure 2 shows the distribution of differential genes upon each treatment and emphasizes that only a minor proportion of genes co-expressed with both peptides (only 30 genes were induced and 13 genes were repressed by both peptides, see also Additional Files 3.5 and 3.6), providing an initial indication of the differential response of S.