BLASTN with -F F flag and an e-value
threshold of 0.00005 was performed using all reads from each
sample against the universal single copy genes from organisms for
which at least 25 of the 31 gene sequences were available. Only the
best BLAST hit was taken for each read and only if at least 80% of
the read aligned against a bacterial gene with at least 85% identity.
Coverage was measured in RPKM