Skip to main content
. 2010 May 5;285(29):22082–22090. doi: 10.1074/jbc.M110.117713

FIGURE 2.

FIGURE 2.

The impact of two human gut acetogens on microbial metabolism in the ceca of gnotobiotic mice. A, multiplex RNA-Seq analysis of the B. hydrogenotrophica transcriptome. The heat map shows selected B. hydrogenotrophica genes, expressed in the ceca of B. thetaiotaomicron (Bt)/B. hydrogenotrophica (Bh) bi-associated mice and in vitro during growth of B. hydrogenotrophica in MA4 medium containing nine different substrates. PPDE > 0.99. Carbon sources were supplied at 1% w/v. The maximal relative expression across a row is red; the minimum is green. stat, stationary phase (note that all other cultures were harvested during mid-log phase). Rumhyd is the locus tag for B. hydrogenotrophica (previously known as R. hydrogenotrophicus). PTS, phosphotransferase system. B, targeted tandem mass spectrometry analysis of amino acid levels. C, nontargeted GC/MS analysis of cecal contents. The data are expressed as unit-less peak areas, normalized to the total ion chromatogram for the cecal sample. 3-IAA, 3-indoleacetic acid; 4-HPA, 4-hydroxyphenylacetic acid. D–H, cecal contents from mice, colonized with either acetogen plus B. thetaiotaomicron or with B. thetaiotaomicron alone, were assayed for NAD+, NADH (D; n = 4–5/group), polyglucose- and polyfructose-containing polysaccharides (E; n = 14–15/group), acetate (F; n = 14–15 animals/group), succinate (G; n = 14–15/group), and propionate (H; n = 14–15/group). The mean values ± S.E. are plotted. *, p < 0.05 based on analysis of variance, except B and C (Student's t test). Quantitative PCR assays revealed the following levels of colonization in the different groups of mice studied: B. thetaiotaomicron mono-association, 7.5 × 1010 ± 1.3 × 1010 genome equivalents/g of wet cecal content, B. thetaiotaomicron/B. hydrogenotrophica bi-association, 6.5 × 1010 ± 9.3 × 109 (B. thetaiotaomicron), 9.4 × 109 ± 2.1 × 109 (B. hydrogenotrophica), and B. thetaiotaomicron/M. formatexigens (Mf) bi-association, 3.1 × 1010 ± 6.3 × 109 (B. thetaiotaomicron), 8.4 ± 109 ± 6.3 × 108 (M. formatexigens); n = 4–5 animals group (three independent experiments).