Organism-specific depletion of highly abundant RNA species from bacterial total RNA

We assess the mRNA-enrichment performance of a custom-made non-mRNA depletion protocol in comparison to a commercially available mRNA-enrichment kit (Ribo-off, Vazyme). Whereas most available kits focus only on removal of rRNA, our method also targets the transfer-messenger RNA (tmRNA). tmRNA was shown to consume up to 25% of the reads in RNA-sequencing data of Pseudomonas aeruginosa. Our established depletion technique is based on the targeting of overly abundant RNA species (16S and23S rRNA, tmRNA) in total RNA preparations of Pseudomonas aeruginosa PA14 by hybridization with organism-specific DNA probes and subsequent degradation by RNase H treatment. While introducing no systematic bias into the gene expression profile we were able to increase the mRNA read share of the total reads in the samples treated with our mRNA-enrichment protocol to 93% - 99%. Therefore, our custom-made depletion technique outcompeted the commercially available reference kit (72% mRNA share) and represents a cost-efficient mRNA-enrichment method for high-throughput next-generation sequencing. Total RNA preparations from Pseudomonas aeruginosa PA14 harvested in exponential or stationary growth phase were treated with a custom-made mRNA enrichment protocol or a reference depletion kit (Ribo-off, Vazyme). Experiment was performed in two biological and two technical replicates.