cow rumen metatranscriptome
Total RNA was extracted from the solid rumen samples. Meta-Bacteria Ribo-Zero rRNA removal kit (Epicentre) was used to remove rRNAs from the total RNA preparations. The double-stranded cDNAs were synthesized by using the Superscript III double-stranded cDNA synthesis kit (Invitrogen, Carlsbad, CA, USA) with random hexamers. The resultant cDNAs were converted into single-stranded template DNA (sstDNA) libraries by using the GS DNA Library Preparation kit (Roche Applied Science, USA). The sstDNA libraries were clonally amplified in a bead-immobilized form by using the GS emPCR kit and sequenced on a Roche 454 Genome Sequencer FLX instrument (Roche Applied Science).