Relative abundance of 18 major bacterial genera found in the sequence pool of eight different urine samples are shown for the two 16S rDNA regions. Groups denoted “”other”" represent minor groups classified. Y-axis represents relative abundance. B: Heat map showing the relative abundance of bacterial genera across urine samples of eight healthy females. Genera denoted as phylum_genus, samples denoted as samplenumber_V1V2 or V6. Taxa marked with asterisk (*) could not be assigned to any genera, and are shown at the lowest common Linsitinib cost taxon: family and order. Color intensity of the heat map is directly

proportional to log 10 scale of the abundance normalized sequence data as done by MEGAN. Keeping the same parameters XMU-MP-1 in vivo as for the analysis at higher taxonomic levels, a small number of bacterial reads from the V1V2 and V6 dataset were assigned to species level, see Additional file 1: Table S1. When comparing to previous reports from literature [9, 17, 37, 42–81], nine out of the 45 species listed are associated with UTI. Twenty of the species listed represent uncultured bacteria, many of them with an unknown pathogenic potential (Additional file 1: Table S1). Variation between urine samples from different individuals The distribution of the different taxa differed markedly among the urine specimens. 16S rDNA sequences from the phyla Firmicutes and Bacteroidetes were found in all

urine samples. Sequences from Proteobacteria and Actinobacteria were observed in 6/8 and 5/8 urine samples respectively, while sequences from Fusobacteria were identified in only 2 samples. The remaining six phyla defined in our pooled urine sequence dataset were only detected once among the urine samples; Spirochaetes, Chloroflexi, Fibrobacteres and Acidobacteria in sample F7, Tenericutes in sample F4 and Synergistetes in sample F2. These results indicate that there is a noticeable intra-individual variation in urine 16S rDNA

sequences even at the phylum level. The interpersonal microbial sequence diversity and the distribution of bacterial DNA at the genus level in each individual are shown in the heat map in Figure 2B. nearly In the majority of the urine specimens (6 out of 8) one genus was dominant, i.e. represented by at least 75% of the reads, while in two specimens (sample F7 and F8) there was a more even distribution among the represented genera (Figure 2B). A polymicrobial state is suggested for all but a single urine specimen based on both of the 16S rDNA sequence datasets. The exception was sample F3, which showed only the presence of Lactobacillus based on the V1V2 reads, while the V6 amplicon sequence data identified seven additional bacterial genera, though at a low frequency. The most frequently identified genus was Prevotella, with sequences present in 7 out of 8 urine samples.