Relative distribution of total bacteria (cultivable species and uncultured phylotypes) in tissues from non-tumor and tumor sites of OSCC subjects characterized by HOMD. Core of pie chart shows percentage distribution of total 914 filtered sequences in terms of their % homology to curated 16S rRNA sequences in HOMD. Outer concentric of pie chart depicts the oral bacterial taxa in combined library; sequences with >98% identity: named cultured species (78.6%), unnamed cultured species (5.9%) and yet-uncultured phylotypes (3.8%); and sequences with <98% identity (11.7%) were considered as unclassified sequences characterized only to genus level. Venn diagrams correlates with the corresponding section of pie chart as indicated by line except for the unclassified sequences. Inset values in two subsets (non-tumor and tumor) represents observed bacterial species unique to that particular library. Values in overlapping section of subsets reflect oral taxa common to both sites.