Fig. 1

16S-RNA-seq accurately quantifies microbe viability in simple synthetic communities. a Expected community structures of ten live/dead Escherichia coli and Streptococcus sanguinis mixtures in DNA and RNA libraries: group (1) 100% live E. coli (DNA library) and 100% E. coli expected in RNA library; (2) 100% dead E. coli (DNA) and 0% E. coli expected in RNA libraries; (3) 100% live S. sanguinis (DNA) and 100% S. sanguinis (RNA); (4) 100% dead S. sanguinis (DNA) and 0% S. sanguinis expected (RNA); (5) 50% live E. coli and 50% live S. sanguinis (DNA), same proportion expected in RNA libraries; (6) 50% dead E. coli and 50% dead S. sanguinis (DNA), no signal expected in RNA libraries; (7) 50% live E. coli, 25% live S. sanguinis, and 25% dead S. sanguinis (DNA) and 67% E. coli and 33% S. sanguinis (RNA); (8) 25% live E. coli and 25% dead E. coli, 50% live S. sanguinis (DNA), and 67% S. sanguinis and 33% E. coli (RNA); (9) 50% live E. coli, 50% dead S. sanguinis (DNA), and 100% E. coli (RNA); and (10) 50% dead E. coli and 50% live S. sanguinis (DNA) and 100% S. sanguinis (RNA). b 16S rRNA gene copy numbers detected from the DNA and RNA extractions from 10 synthetic cultures. c Relative abundances of synthetic community members by 16S-RNA-seq in DNA and RNA libraries. Each experiment had three biological replicates. As expected, the experimental results closely follow the predicted simple community composition, albeit small fluctuations in the relative abundance of the microbes