Total numbers approached 1010 (g wet wt)-1, while numbers capable of growing on sugar-free media after 7 d were about 108 (g wet wt)-1. Actual counts on Trypticase medium varied from 0.8 × 107 to 3.5 × 108 (g wet wt)-1. Monensin decreased numbers in Trypticase medium by an average of 92% to 105-106 (g wet wt)-1. Amino acid utilizers were on average only slightly (26%) fewer in number than Trypticase utilizers. Figure 1 Most-probable-numbers (MPN) counts of Trypticase

and amino acid-utilising bacteria in faeces from human omnivorous (O2 and O3) and vegetarian (V1 and V2) donors. Results are from 7-d counts. Error bars represent 95% confidence levels. Bacterial isolates A total of 53 isolates was isolated EGFR inhibitor from the highest dilutions of faecal bacteria from two ominivores and one vegetarian. Twenty-eight survived repeated sub-culture, of which 24 gave full length or near full length 16S rRNA gene sequences (Table 3). The remaining four were identified from partial sequences. None of the isolates was asaccharolytic, growth being increased significantly in all cases by the addition of glucose to the medium. The bacteria enriched from the faecal samples appeared

to be different depending on whether the substrate was peptides or amino acids. Shigella spp. and E. coli were more numerous in the amino acids-containing cultures. Other pathogens that were enriched included Enterococcus faecalis, Staphylococcus sp. and Eggerthella lenta. Table 3 Identity of bacteria isolated from peptides or amino acids enrichments Isolate Vol/ diln Identification % Sim Phylum Class Order Accession no. Peptides             1 O1/5 Clostridium DNA/RNA Synthesis inhibitor perfringens 99 Firmicutes Clostridia Clostridiales GU968162 3 O1/5 Clostridium orbiscindens 99 Firmicutes Clostridia Clostridiales GU968163 5 O1/5 Shigella sonnei 98 Proteobacteria Gammaproteobacteria Enterobacteriales GU968164 6 O1/6 Enterococcus faecium 99 Firmicutes Bacilli Lactobacillales GU968165 8 O1/6 Bacteroides ovatus 99 Bacteroidetes Ribonucleotide reductase Bacteroidia

Bacteroidales GU968166 12 O2/5 C. orbiscindens 97 Firmicutes Clostridia Clostridiales 893 bp 13 O2/5 Clostridium innocuum 98 Firmicutes Clostridia Clostridiales GU968167 14 O2/5 B. ovatus 93 Bacteroidetes Bacteroidia Bacteroidales GU968168 15 O2/5 Blautia hydrogenotrophica 95 Firmicutes Clostridia Clostridiales GU968169 16 O2/6 C. orbiscindens 95 Firmicutes Clostridia Clostridiales 877 bp 17 O2/6 C. orbiscindens 99 Firmicutes Clostridia Clostridiales GU968170 21 V1/5 Bacteroides fragilis 99 Bacteroidetes Bacteroidia Bacteroidales GU968171 22 V1/5 Escherichia coli 99 Proteobacteria Gammaproteobacteria Enterobacteriales GU968172 23 V1/5 B. fragilis 98 Bacteroidetes Bacteroidia Bacteroidales GU968173 25 V1/6 B. fragilis 99 Bacteroidetes Bacteroidia Bacteroidales GU968174 27 V1/6 E. faecium 99 Firmicutes Bacilli Lactobacillales GU968175 Amino acids             29 O1/6 Shigella sp.