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Fecal transplants successful for treating C. difficile infection           

Distasteful though it sounds, the transplantation of fecal matter is more successful for treating Clostridium difficile infections than previously thought.

The research, published in the open access journal Microbiome, reveals that healthy changes to a patient’s microbiome are sustained for up to 21 weeks after transplant, and has implications for the regulation of the treatment.

Clostridium difficile infections are a growing problem, leading to recurrent cases of diarrhea and severe abdominal pain, with thousands of fatalities worldwide every year. The infection is thought to work by overrunning the intestinal microbiome - the ecosystem of microorganisms that maintain a healthy intestine.

Alexa Weingarden, Antonio Gonzalez, Yoshiki Vazquez-Baeza, Sophie Weiss, Gregory Humphrey, Donna Berg-Lyons, Dan Knights, Tatsuya Unno, Aleh Bobr, Johnthomas Kang, Alexander Khoruts, Rob Knight and Michael J Sadowsky

Dynamic Changes in Short- and Long-Term Bacterial Composition Following Fecal Microbiota Transplantation for Recurrent Clostridium difficile Infection

Microbiome 2015

DOI: 10.1186/s40168-015-0070-0 

Baleen whales’ digestive tract resembles that of both carnivores and herbivores

Baleen whales are the largest animals on our planet, and they live by eating the tiniest. These whales survive on copepods, krill, and small fish, and must eat massive amounts in order to gain and maintain their weight. Research into right whales’ microbiome – the community of microbes that live in an animal’s guts and helps it process its food – has found a unique feature that helps baleen whales make the most out of their diets: their microbiome includes bacteria found in both carnivores’ and ruminant herbivores’ digestive systems, allowing the whales to digest both meat and crustaceans’ chitin-rich shells.

This research began when the study’s second author, graduate student Annabel Beichman, collected fecal samples of right whales with the University of Vermont’s Joe Roman. Still an undergraduate at the time, Beichman hoped to use DNA sequencing technology to aid conservation research. The fecal samples she and Roman collected gave them information about what sort of microbes were present in the whales’ digestive tracts. After extracting and sequencing DNA from the samples, they found that the microbes present resembled those of meat-eating predators and, unexpectedly, cows.

The anaerobic bacteria found in the guts of cattle help break down cellulose, allowing the cattle to get the most out of their plant-based diet. Baleen whales’ diets contain very little cellulose, but they do contain large amounts of chitin. In fact, the chitin-rich shells of copepods and other crustaceans make up as much as 10% of baleen whales’ diets. Without a microbial community that could help digest the chitin, the whales could only expel the shells, losing all of the potential nutrients locked in them.

While researchers were, until now, unaware that baleen whales’ microbiomes partially resemble the microbiomes of cows, they did know that whales’ digestive anatomy features a multi-chambered foregut like that found in their ruminant cousins. (Whales share common ancestors with, and are related to, cattle and other terrestrial ruminants.) Many researchers had believed that this foregut was purely vestigial and served no real purpose in the whales’ lives, but the dual microbiome suggests otherwise. The chitin-digesting anaerobic bacteria likely thrive in this foregut.

This dual microbiome gives whales a unique evolutionary advantage by allowing them to maximize their energy intake when feeding, and may therefore have played a key role in making whales one of the most successful groups of animals in the oceans. This evolutionary advantage is likely why the foregut was maintained even as whales’ environment and diet began to diverge drastically from those of their cousins.

The researchers involved in this study hope to continue sampling baleen whales’ microbiomes, and to extend their research to the microbiomes of toothed whales, whose diets have very little chitin. When we know more about the microbiomes of toothed whales, we may also be able to better care for the toothed whales in captivity.

Based on materials provided by Harvard University

Image credit: Peter Duley, NOAA

Journal reference: Jon G. Sanders, Annabel C. Beichman, Joe Roman, Jarrod J. Scott, David Emerson, James J. McCarthy, Peter R. Girguis. Baleen whales host a unique gut microbiome with similarities to both carnivores and herbivores. Nature Communications, 2015; 6: 8285 DOI:10.1038/ncomms9285

Submitted by volk-morya

To all the vegetarians out there, this is your reminder about day after poops when you eat any bite of meat and drink alcohol.