Postprandial remodeling of the gut microbiota in Burmese pythons. ISME J

Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309-0215, USA.
The ISME Journal (Impact Factor: 9.3). 11/2010; 4(11):1375-85. DOI: 10.1038/ismej.2010.71
Source: PubMed


The vertebrate gut microbiota evolved in an environment typified by periodic fluctuations in nutrient availability, yet little is known about its responses to host feeding and fasting. As many model species (for example, mice) are adapted to lifestyles of frequent small meals, we turned to the Burmese python, a sit-and-wait foraging snake that consumes large prey at long intervals (>1 month), to examine the effects of a dynamic nutrient milieu on the gut microbiota. We used multiplexed 16S rRNA gene pyrosequencing to characterize bacterial communities harvested from the intestines of fasted and digesting snakes, and from their rodent meal. In this unprecedented survey of a reptilian host, we found that Bacteroidetes and Firmicutes numerically dominated the python gut. In the large intestine, fasting was associated with increased abundances of the genera Bacteroides, Rikenella, Synergistes and Akkermansia, and with reduced overall diversity. A marked postprandial shift in bacterial community configuration occurred. Between 12 h and 3 days after feeding, Firmicutes, including the taxa Clostridium, Lactobacillus and Peptostreptococcaceae, gradually outnumbered the fasting-dominant Bacteroidetes, and overall 'species'-level diversity increased significantly. Most lineages seemed to be indigenous to the python rather than ingested with the meal, but a dietary source of Lactobacillus could not be ruled out. Thus, the observed large-scale alterations of the gut microbiota that accompany the Burmese python's own dramatic physiological and morphological changes during feeding and fasting emphasize the need to consider both microbial and host cellular responses to nutrient flux. The Burmese python may provide a unique model for dissecting these interrelationships.

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Available from: Elizabeth Kate Costello, Feb 11, 2015
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    • "Whereas species with more flexible diets may exhibit wider variance in gut communities even in natural populations (Nelson et al. 2013; Bolnick et al. 2014b,c), obligate herbivores are likely to be more reliant than other species on stable, specifically functioning gut communities. Studies characterizing reptilian gut microbiota are sparse (Costello et al. 2010; Hong et al. 2011; Keenan et al. 2013; Gaillard 2014) despite the wide-ranging dietary modes and repeated independent evolution of herbivory (Vitt 2004). Thus, further work on a diverse assemblage of reptilian species across a variety of dietary modes is needed to understand the evolution of mutualistic gut microbes in this group. "
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    • "Improved methods of comparing microbial diversity A common approach in microbial community ecology studies is to assess ecosystem resilience and recovery through comparison of univariate metrics and visualization of community data in ordination space (Fierer et al., 2008; Costello et al., 2010; Dethlefsen and Relman, 2010; Caporaso et al., 2011; Werner et al., 2011; Zhao et al., 2012; Shade et al., 2013). These methods often oversimplify and condense complex community data into a single datum point, which cannot be partitioned into independent alpha-and beta-components (Jost, "
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    The ISME Journal 02/2015; 9:425-435. DOI:10.1038/ismej.2014.139 · 9.30 Impact Factor
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    • "The absence of free nutrients or physiological responses of hosts to fasting may exert similar selection on resident microorganisms and cause complementary shifts in diversity and abundances of taxa. For example, the microbial genus Akkermansia consumes host-produced mucus (Derrien et al., 2004) and increases in relative abundance in response to fasting in hamsters (Sonoyama et al., 2009) and pythons (Costello et al., 2010). To date, there has not been a comprehensive, comparative study investigating the effects of fasting on gut microbial communities of different host taxa. "
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