Expressed sequence tag (EST) sequencing results. (a) and (c) present sequencing summaries for the host (termite gut tissue) and symbiont cDNA libraries, respectively. (b) and (d) are the taxonomic distributions of top BLASTX hits for putative transcripts from the termite gut and symbiont libraries (respectively). Hits producing an E-value < 10-5 were considered significant. The charts illustrate that the majority of transcripts sequenced from the termite gut library were homologous to insect sequences, whereas the majority of transcripts obtained from the symbiont library were homologous to genes previously sequenced from unicellular eukaryotes.