Correlation between presence of cellulase genes and cellulase activity. (A) Phylogenetic relationships and results of diplogastrid species tested for cellulase transcripts and activity. These 10 species were used in Roche 454 sequencing. The tree was reconstructed from 4,043 bp of concatenated ribosomal protein genes by heuristic search using the maximum likelihood criterion in the PAUP*4.0b10 software as described in Mayer et al. (2009) [11, 12]. Numbers at nodes indicate bootstrap values. The presence of cellulase transcripts and observed cellulase activity in worm supernatants is indicated. The tree was rooted by Koerneria sudhausi. (B) Neighbour-joining tree of 246 bp of aligned EST contigs from Roche 454 transcriptomes encoding CBM49 domains of cellulases (see additional file 1). The best-fit substitution model (TrNef+G) has been selected by Modeltest 3.7 (Posada) corresponding to equal base frequencies, Nst = 6, substitution rates of A-C = 1, A-G = 1.1039, A-T = 1, C-G = 1, C-T = 1.7501, G-T = 1.0000; proportion of invariable sites I = 0; gamma distribution shape parameter α = 0.9033. Numbers at nodes indicate bootstrap values of 1,000 replications.