Submitted to: Applied and Environmental Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/7/2016
Publication Date: 9/9/2016
Publication URL: http://handle.nal.usda.gov/10113/63276
Citation: Trachsel, J., Bayles, D.O., Looft, T.P., Levine, U.Y., Allen, H.K. 2016. Function and phylogeny of bacterial butyryl coenzyme A:acetate transferases and their diversity in the proximal colon of swine. Applied and Environmental Microbiology. 82(22):6788-6798. http://dx.doi.org/10.1128/AEM.02307-16.
Interpretive Summary: The health of all animals is dependent on the microorganisms that live in and on them. The proper balance of these microbes is critical for optimum health and resistance to disease. This relationship is especially important in the mammalian intestinal tract. In the colon, bacteria turn undigested food into various compounds that nourish host tissues. The compound butyrate is produced by colonic bacteria and has been shown to improve gut and immune health. Currently, the community of butyrate-producing bacteria is not well studied in swine. Here we have characterized the way in which some swine-associated bacteria produce butyrate, and we have developed tools to investigate this community. The results show that the swine gut is home to diverse butyrate-producing bacteria. Also, the potential for butyrate production can be studied by sequencing the gene that encodes butyrate production. This research is useful to scientists and stakeholders interested in swine-associated bacterial communities. The probes we designed could be used in investigations of how the butyrate-producing bacterial community relates to health, disease, and foodborne pathogen carriage.
Technical Abstract: Studying the host-associated butyrate-producing bacterial community is important because butyrate is essential for colonic homeostasis and gut health. Previous research has identified the butyryl-coA:acetate transferase (18.104.22.168) as a the main gene for butyrate production in intestinal ecosystems; however, this gene family (but) remains poorly defined. To develop analysis tools for this community, twelve putative but genes were identified in the genomes of nine butyrate-producing bacteria from the swine intestinal tract. Functional analyses revealed that eight of these genes had strong But enzyme activity. When but paralogues were found within a genome, only one paralogue per genome encoded strong activity, with the exception of one strain in which no highly active But protein was identified. Degenerate primers were designed to the functional but genes and tested by amplifying environmental but sequences from DNA and RNA extracted from swine colonic contents. The results show diverse but sequences from swine-associated butyrate-producing bacteria, most of which clustered near functionally confirmed sequences. This work will improve future studies of the butyrate-producing community and inform its relationship to host health and disease.