Bovine Rumen Research Articles

Ruminococcal cellulosome systems from rumen to human.

A cellulolytic fiber-degrading bacterium, Ruminococcus champanellensis, was isolated from human faecal samples, and its genome was recently sequenced. Bioinformatic analysis of the R. champanellensis genome revealed numerous cohesin and dockerin modules, the basic elements of the cellulosome, and manual sequencing of partially sequenced genomic segments revealed two large tandem scaffoldin-coding genes that form part of a gene cluster. Representative R. champanellensis dockerins were tested against putative cohesins, and the results revealed three different cohesin-dockerin binding profiles which implied two major types of cellulosome architectures: (i) an intricate cell-bound system and (ii) a simplistic cell-free system composed of a single cohesin-containing scaffoldin. The cell-bound system can adopt various enzymatic architectures, ranging from a single enzyme to a large enzymatic complex comprising up to 11 enzymes. The variety of cellulosomal components together with adaptor proteins may infer a very tight regulation of its components. The cellulosome system of the human gut bacterium R. champanellensis closely resembles that of the bovine rumen bacterium Ruminococcus flavefaciens. The two species contain orthologous gene clusters comprising fundamental components of cellulosome architecture. Since R. champanellensis is the only human colonic bacterium known to degrade crystalline cellulose, it may thus represent a keystone species in the human gut.

Isolation, characterization, and invitro evaluation of bovine rumen submucosa films of collagen or chitosan-treated collagen.

Bovine rumen is hitherto considered as an inedible waste of meat industry. The rumen tissues can be used as an alternative source of collagen to produce biocompatible materials for clinical application. In an effort to develop a functional biomaterial from the inedible mammalian tissues, this study aims to isolate and characterize bovine rumen submucosa. Initially, the rumen tissue was sequentially processed using chemical and enzymatic treatment to decellularize, neutralize, stabilize, and to produce a native collagen matrix which is referred as collagen film (COL-F). Thus, prepared matrix was treated with 1% (w/v) chitosan solution to produce a hybrid film which is referred as collagen-chitosan film (COL/CS-F). The comparative study includes the evaluation of physical, chemical, and biological properties of the biofilms prepared. The surface topology of COL-F exhibited a continuous collagenous network with fibrous nature, while the chitosan treatment provided smooth plain surface to the parent film. Incorporation of chitosan in COL-F increased the tensile properties, as well as the thermal stability and durability of the films. The Fourier Transform Infrared spectroscopy results revealed the presence of respective amide peaks, which corresponds to protein (collagen), and the evidence of collagen-chitosan interlinking. The submucosa layer was electrophoretically found to have type I collagen. The X-ray diffraction data showed the presence of amorphous and crystalline peak which attributes to the triple helical structure of collagen in the films. Cytotoxicity studies on the films were performed invitro using human keratinocytes. The results of cell viability and proliferation demonstrated that COL-F and COL/CS-F exhibit good biocompatibility and therefore can augment cell infiltration and proliferation. However, enhanced cellular activity was observed on the chitosan treated COL-F. These observations demonstrate that the biofilms prepared in this study can be used as an alternative functional biomaterial in tissue engineering.

Evaluation of Lactococcus lactis Isolates from Nondairy Sources with Potential Dairy Applications Reveals Extensive Phenotype-Genotype Disparity and Implications for a Revised Species.

Lactococcus lactis is predominantly associated with dairy fermentations, but evidence suggests that the domesticated organism originated from a plant niche. L. lactis possesses an unusual taxonomic structure whereby strain phenotypes and genotypes often do not correlate, which in turn has led to confusion in L. lactis classification. A bank of L. lactis strains was isolated from various nondairy niches (grass, vegetables, and bovine rumen) and was further characterized on the basis of key technological traits, including growth in milk and key enzyme activities. Phenotypic analysis revealed all strains from nondairy sources to possess an L. lactis subsp. lactis phenotype (lactis phenotype); however, seven of these strains possessed an L. lactis subsp. cremoris genotype (cremoris genotype), determined by two separate PCR assays. Multilocus sequence typing (MLST) showed that strains with lactis and cremoris genotypes clustered together regardless of habitat, but it highlighted the increased diversity that exists among "wild" strains. Calculation of average nucleotide identity (ANI) and tetranucleotide frequency correlation coefficients (TETRA), using the JSpecies software tool, revealed that L. lactis subsp. cremoris and L. lactis subsp. lactis differ in ANI values by ∼14%, below the threshold set for species circumscription. Further analysis of strain TIFN3 and strains from nonindustrial backgrounds revealed TETRA values of <0.99 in addition to ANI values of <95%, implicating that these two groups are separate species. These findings suggest the requirement for a revision of L. lactis taxonomy.

Draft Genome Sequence of Streptococcus equinus (Streptococcus bovis) HC5, a Lantibiotic Producer from the Bovine Rumen

Streptococcus equinus (Streptococcus bovis) HC5 is a bacteriocinogenic lactic acid bacterium with simple growth requirements. The draft genome sequence of S. equinus HC5 consists of 1,846,241 bp, with a G+C content of 37.04%. In silico analysis indicated that S. equinus HC5 might be useful to control bacteria that are detrimental to livestock animals.

Vaccination of cattle with a methanogen protein produces specific antibodies in the saliva which are stable in the rumen

Methane is produced in the rumen of cattle by a group of archaea (single-celled organisms forming a domain distinct from bacteria and eucarya) called methanogens. Vaccination against methanogens has the potential to reduce methane emissions by inducing antibodies in saliva which are transferred to the rumen and diminish the ability of methanogens to produce methane. Since it is likely that an effective vaccination strategy will need to produce high levels of methanogen-specific antibody in the saliva; the choice of adjuvant, route of vaccination and stability of saliva-derived antibody in the rumen all need to be considered. In this study, stability of IgA and IgG in rumen fluid was determined using an in vitro assay. IgA levels in cattle saliva were reduced by only 40% after 8h exposure to rumen contents while IgG levels were reduced by 80%. These results indicated that antibody is relatively stable in the bovine rumen. A trial was conducted in cattle to investigate induction of immune responses to a methanogen protein, recombinant glycosyl transferase protein (rGT2) from Methanobrevibacter ruminantium M1. Groups of cattle (n=6) were vaccinated subcutaneously with rGT2, formulated with Montanide ISA61 with or without the TLR4 agonist, monophosphoryl lipid A (MPL). A control group (n=6) was not vaccinated. Strong antigen-specific IgG and moderate IgA responses were measured in the serum and saliva of the vaccinated animals and antibody was also detected in the rumen.

Isolation and characterization of novel lipases/esterases from a bovine rumen metagenome.

Improving the health beneficial fatty acid content of meat and milk is a major challenge requiring an increased understanding of rumen lipid metabolism. In this study, we isolated and characterized rumen bacterial lipases/esterases using functional metagenomics. Metagenomic libraries were constructed from DNA extracted from strained rumen fluid (SRF), solid-attached bacteria (SAB) and liquid-associated rumen bacteria (LAB), ligated into a fosmid vector and subsequently transformed into an Escherichia coli host. Fosmid libraries consisted of 7,744; 8,448; and 7,680 clones with an average insert size of 30 to 35 kbp for SRF, SAB and LAB, respectively. Transformants were screened on spirit blue agar plates containing tributyrin for lipase/esterase activity. Five SAB and four LAB clones exhibited lipolytic activity, and no positive clones were found in the SRF library. Fosmids from positive clones were pyrosequenced and twelve putative lipase/esterase genes and two phospholipase genes retrieved. Although the derived proteins clustered into diverse esterase and lipase families, a degree of novelty was seen, with homology ranging from 40 to 78 % following BlastP searches. Isolated lipases/esterases exhibited activity against mostly short- to medium-chain substrates across a range of temperatures and pH. The function of these novel enzymes recovered in ruminal metabolism needs further investigation, alongside their potential industrial uses.Electronic supplementary materialThe online version of this article (doi:10.1007/s00253-014-6355-6) contains supplementary material, which is available to authorized users.

CARACTERIZAÇÃO QUÍMICA DE RESÍDUOS DE ORIGEM ANIMAL E COMPORTAMENTO DE EISENIA ANDREI

This research aims to value the chemical composition, the food preference and the earthworms Eisenia andrei (Bouche, 1972) multiplication, from animals residues. The used residues were bovine rumen content, rabbits manure, ovine manure and bovine manure. The evaluation of vermicomposting process consisted of four treatments with six repetitions. PVC black pots containing 2 kg of the dry matter residues were used for each one of the repetitions, in which 90 clitellates earthworms were inoculated. It was evaluated the residues chemical composition at the time of the experiment installation, and after 90 days of vermicomposting were carried out the earthworms reproduction. The evaluation of food preference consisted four repetitions for each studied residues. PVC role pots with each treatment residues inside, were introduced in a composted with earthworms. The food preference was valued by the residues after 14 days. The food preference and the earthworms’ reproduction are favored by the bovine manure and by the rumen bovine content. The rabbit manure has higher levels of chemical nutrients and heavy metals then the bovine manure, ovine manure and rumen bovine content.

Isolation and Identification of Enterococcus Faecium and Enterococcus Cecorum from Bovine Rumen Using Modern Techniques

Isolation and Identification of Enterococcus Faecium and Enterococcus Cecorum from Bovine Rumen Using Modern Techniques

Metatranscriptomic analyses of plant cell wall polysaccharide degradation by microorganisms in the cow rumen.

The bovine rumen represents a highly specialized bioreactor where plant cell wall polysaccharides (PCWPs) are efficiently deconstructed via numerous enzymes produced by resident microorganisms. Although a large number of fibrolytic genes from rumen microorganisms have been identified, it remains unclear how they are expressed in a coordinated manner to efficiently degrade PCWPs. In this study, we performed a metatranscriptomic analysis of the rumen microbiomes of adult Holstein cows fed a fiber diet and obtained a total of 1,107,083 high-quality non-rRNA reads with an average length of 483 nucleotides. Transcripts encoding glycoside hydrolases (GHs) and carbohydrate binding modules (CBMs) accounted for 1% and 0.1% of the total non-rRNAs, respectively. The majority (98%) of the putative cellulases belonged to four GH families (i.e., GH5, GH9, GH45, and GH48) and were primarily synthesized by Ruminococcus and Fibrobacter. Notably, transcripts for GH48 cellobiohydrolases were relatively abundant compared to the abundance of transcripts for other cellulases. Two-thirds of the putative hemicellulases were of the GH10, GH11, and GH26 types and were produced by members of the genera Ruminococcus, Prevotella, and Fibrobacter. Most (82%) predicted oligosaccharide-degrading enzymes were GH1, GH2, GH3, and GH43 proteins and were from a diverse group of microorganisms. Transcripts for CBM10 and dockerin, key components of the cellulosome, were also relatively abundant. Our results provide metatranscriptomic evidence in support of the notion that members of the genera Ruminococcus, Fibrobacter, and Prevotella are predominant PCWP degraders and point to the significant contribution of GH48 cellobiohydrolases and cellulosome-like structures to efficient PCWP degradation in the cow rumen.

A multiresidue screen for the analysis of toxicants in bovine rumen contents.

Analysis of rumen contents is helpful in solving poisoning cases when ingestion of a toxic substance by cattle or other ruminant animals is suspected. The most common technique employs extraction of the sample with organic solvent followed by clean-up method(s) before analysis with gas chromatography-mass spectrometry equipped with a library of mass spectra to help identify unknowns. A rapid method using magnesium sulfate, primary secondary amine, and C18 sorbents following principles of QuEChERS to clean up rumen contents samples is reported herein. The method was validated to analyze fortified bovine rumen contents to detect commonly found organophosphorus pesticides, carbamates, and several other compounds such as atropine, 4-aminopyridine, caffeine, scopolamine, 3-chloro-4-methylaniline, strychnine, metaldehyde, and metronidazole. For each compound, the ratio of 2 ions from the mass spectrum was monitored in fortified rumen contents. The ion ratio of fortified sample was compared with the ion ratio of standard sample spectrum and was found to be within 20%, with the exception of aldicarb and 4-aminopyridine with ion ratio of 26% and 29%, respectively. Usefulness of the method was demonstrated by not only analyzing bovine rumen contents but also canine and avian gastrointestinal contents submitted for organic chemical screening.

Uso de indicadores indigestíveis obtidos in situ e in vivo para determinar a digestibilidade de nutrientes em equinos

Objetivou-se estudar a viabilização dos indicadores internos, celulose (CELi) e lignina (LIGi) indigestíveis, obtidos pelas técnicas in situ e in vivo,para predizer a digestibilidade de nutrientes em equinos. Foram utilizados quatro cavalos castrados, por meio de delineamento em blocos ao acaso. Os tratamentos consistiram de metodologias de avaliação de digestibilidade, como a coleta total de fezes (CT) e o uso de indicadores internos, CELi e LIGi, obtidos pelas técnicas in situ (IS) na cavidade ruminal de bovinos e in vivo (IV) nos equinos, por meio da técnica do saco de náilon móvel (TSNM), totalizando cinco tratamentos. A ingestão diária de MS foi de 2,0% do peso vivo de feno de coast-cross. A CELi-IV promoveu a melhor taxa de recuperação do indicador, igualando-se à CT, em 100,31%, enquanto a LIGi resultou nas piores taxas, na média 76,45%, para ambas as técnicas (P&lt;0,05). As estimativas dos coeficientes de digestibilidade dos nutrientes foram adequadamente preditas pela CELi, obtidos IS e IV em que os valores observados foram de 46,41, 48,16, 46,90, 47,92 e 45,51% para MS, MO, PB, FDN e EB, respectivamente. Concluiu-se que a CELi pode ser obtida in vivo por meio da TSNM em equinos, para predizer a digestibilidade de nutrientes.

Metasecretome-selective phage display approach for mining the functional potential of a rumen microbial community.

BackgroundIn silico, secretome proteins can be predicted from completely sequenced genomes using various available algorithms that identify membrane-targeting sequences. For metasecretome (collection of surface, secreted and transmembrane proteins from environmental microbial communities) this approach is impractical, considering that the metasecretome open reading frames (ORFs) comprise only 10% to 30% of total metagenome, and are poorly represented in the dataset due to overall low coverage of metagenomic gene pool, even in large-scale projects.ResultsBy combining secretome-selective phage display and next-generation sequencing, we focused the sequence analysis of complex rumen microbial community on the metasecretome component of the metagenome. This approach achieved high enrichment (29 fold) of secreted fibrolytic enzymes from the plant-adherent microbial community of the bovine rumen. In particular, we identified hundreds of heretofore rare modules belonging to cellulosomes, cell-surface complexes specialised for recognition and degradation of the plant fibre.ConclusionsAs a method, metasecretome phage display combined with next-generation sequencing has a power to sample the diversity of low-abundance surface and secreted proteins that would otherwise require exceptionally large metagenomic sequencing projects. As a resource, metasecretome display library backed by the dataset obtained by next-generation sequencing is ready for i) affinity selection by standard phage display methodology and ii) easy purification of displayed proteins as part of the virion for individual functional analysis.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-15-356) contains supplementary material, which is available to authorized users.

Expression of the ABC transport proteins MDR1 (ABCB1) and BCRP (ABCG2) in bovine rumen

Rumen fermentation of plant-based forage in bovines is the major site for generation and absorption of short-chain fatty acids. Consequentially, the rumen is also the site for initial exposure to toxins released from diet. Accordingly, we have investigated the expression of bovine ABC transporters in the rumen associated with cytoprotection against xenobiotic exposure, namely MDR1 (ABCB1), MRP2 (ABCC2) and BCRP (ABCG2). Bovine rumen samples from the ventral sac were obtained post-mortem from a commercial slaughterhouse after humane killing. Rumen papilla samples were then prepared for total RNA isolation for RT-PCR, SDS-PAGE/Western blotting and immunohistochemistry. PCR products of the predicted size were observed for both MDR1 and BCRP, but not for MRP2 using bovine-specific primers. β-actin was used as a control transcript. Western blot analysis using C219 primary monoclonal antibody revealed MDR1 protein expression in bovine rumen (Mapp, of ~170-180kD). Immunolocalisation of MDR1 using UIC2 monoclonal antibody within cryosections of bovine rumen showed extensive membrane staining in the cells of the stratum granulosum, stratum spinosum and stratum basale. MDR1 expression was absent from outer stratum corneum. Protein expression and immunolocalisation were also confirmed for BCRP, with prevalent staining in the stratum basale, becoming weaker in the stratum spinosum and stratum granulosum.

Evaluation of bovine rumen contents as a feed for lambs.

This study evaluated effects of increasing levels of dried rumen contents (DRC) on voluntary intake, growth performance, digestibility, nutritive value, N utilization, microbial protein supply (MPS), and purine derivatives excretion (PDE) of lambs fed with Afzelia africana basal forage. Sixteen lambs (13.7 ± 0.1 kg body weight (BW)) were randomly assigned to one of the four eight diets containing 0, 200, 400 and 600 g DRC/kg dry matter (DM) in a completely random design. Intakes of concentrate, DM, crude protein (CP), organic matter (OM), digestible CP (DCP), digestible OM (DOM), digestible energy (DE) and metabolizable energy (ME), CP and OM digestibility, DOM, DCP, DE, ME, N intake and retention, weight gain, cost/kg BW gain, MPS and PDE increased with increasing DRC level up to 400 g/kg DRC and declined at 600 g/kg DRC (P < 0.05; 0.01). Feed conversion ratio and DM digestibility declined as DRC level increased from 0 to 400 g/kg and peaked at 600 g/kg DRC (P < 0.05; 0.01). Forage intake and DE/DCP ratio decreased (P < 0.05; 0.01) progressively with increasing DRC level. Results indicate that DRC can be incorporated up to 400 g/kg in a compounded ration for sheep.

Could Nitrile Derivatives of Turnip (Brassica rapa) Glucosinolates Be Hepato- or Cholangiotoxic in Cattle?

Turnip (Brassica rapa ssp. rapa) and rape (Brassica napus ssp. biennis) and other brassica forage crops are regarded as "safe" feed for cattle during late summer and fall in the North Island of New Zealand when high Pithomyces chartarum spore counts in pastures frequently lead to sporidesmin toxicity (facial eczema). Sporadic acute severe cases of turnip photosensitization in dairy cows characteristically exhibit high γ-glutamyl transferase and glutamate dehydrogenase serum enzyme activities that mimic those seen in facial eczema. The two diseases can, however, be distinguished by histopathology of the liver, where lesions, in particular those affecting small bile ducts, differ. To date, the hepato-/cholangiotoxic phytochemical causing liver damage in turnip photosensitization in cattle is unknown. Of the hydrolysis products of the various glucosinolate secondary compounds found in high concentrations in turnip and rape, work has shown that nitriles and epithionitriles can be hepatotoxic (and nephro- or pancreatotoxic) in rats. These derivatives include β-hydroxy-thiiranepropanenitrile and 3-hydroxy-4-pentenenitrile from progoitrin; thiiranepropanenitrile and 4-pentenenitrile from gluconapin; thiiranebutanenitrile and 5-hexenenitrile from glucobrassicanapin; phenyl-3-propanenitrile from gluconasturtiin; and indole-3-acetonitrile from glucobrassicin. This perspective explores the possibility of the preferential formation of such derivatives, especially the epithionitriles, in acidic conditions in the bovine rumen, followed by absorption, hepatotoxicity, and secondary photosensitization.

Improved culturability of cellulolytic rumen bacteria and phylogenetic diversity of culturable cellulolytic and xylanolytic bacteria newly isolated from the bovine rumen

The phylotypes of rumen bacteria have increased by the accumulation of 16S rRNA gene sequences, and they show a complex microbial community structure in the rumen. However, most of the biochemical properties of rumen bacteria defined by phylotypes are still unknown. We attempted to improve the culturability of cellulolytic bacteria from the rumen using an agar medium (CA) and a gellan gum medium (CG) containing azo-carboxymethylcellulose as a carbon source. We isolated 129 strains from these media, and the numbers of isolates that showed filter paperase, carboxymethylcellulase and xylanase activity were 51, 117 and 105, respectively. The isolates were classified into six phyla by 16S rRNA gene sequences. In accordance with other studies, fibre-adherent rumen bacteria from the phylum Firmicutes were the most abundant cultured isolates obtained (82.2%). Isolates that were unclassified (< 97% similarity) totalled 19.4%, indicating that the media used in this study was successfully able to improve the culturability of rumen cellulolytic bacteria. Moreover, as the Chao1 richness of CG was higher than that of CA, we estimated that, compared with CA, CG supports the growth of a wide variety of rumen bacteria. These results demonstrate that culturable species of ruminal cellulolytic bacteria can be increased using improved culture media.

Thin-layer Chromatographic (TLC) Separations and Bioassays of Plant Extracts to Identify Antimicrobial Compounds

A common screen for plant antimicrobial compounds consists of separating plant extracts by paper or thin-layer chromatography (PC or TLC), exposing the chromatograms to microbial suspensions (e.g. fungi or bacteria in broth or agar), allowing time for the microbes to grow in a humid environment, and visualizing zones with no microbial growth. The effectiveness of this screening method, known as bioautography, depends on both the quality of the chromatographic separation and the care taken with microbial culture conditions. This paper describes standard protocols for TLC and contact bioautography with a novel application to amino acid-fermenting bacteria. The extract is separated on flexible (aluminum-backed) silica TLC plates, and bands are visualized under ultraviolet (UV) light. Zones are cut out and incubated face down onto agar inoculated with the test microorganism. Inhibitory bands are visualized by staining the agar plates with tetrazolium red. The method is applied to the separation of red clover (Trifolium pratense cv. Kenland) phenolic compounds and their screening for activity against Clostridium sticklandii, a hyper ammonia-producing bacterium (HAB) that is native to the bovine rumen. The TLC methods apply to many types of plant extracts and other bacterial species (aerobic or anaerobic), as well as fungi, can be used as test organisms if culture conditions are modified to fit the growth requirements of the species.

Thin-layer chromatographic (TLC) separations and bioassays of plant extracts to identify antimicrobial compounds.

A common screen for plant antimicrobial compounds consists of separating plant extracts by paper or thin-layer chromatography (PC or TLC), exposing the chromatograms to microbial suspensions (e.g. fungi or bacteria in broth or agar), allowing time for the microbes to grow in a humid environment, and visualizing zones with no microbial growth. The effectiveness of this screening method, known as bioautography, depends on both the quality of the chromatographic separation and the care taken with microbial culture conditions. This paper describes standard protocols for TLC and contact bioautography with a novel application to amino acid-fermenting bacteria. The extract is separated on flexible (aluminum-backed) silica TLC plates, and bands are visualized under ultraviolet (UV) light. Zones are cut out and incubated face down onto agar inoculated with the test microorganism. Inhibitory bands are visualized by staining the agar plates with tetrazolium red. The method is applied to the separation of red clover (Trifolium pratense cv. Kenland) phenolic compounds and their screening for activity against Clostridium sticklandii, a hyper ammonia-producing bacterium (HAB) that is native to the bovine rumen. The TLC methods apply to many types of plant extracts and other bacterial species (aerobic or anaerobic), as well as fungi, can be used as test organisms if culture conditions are modified to fit the growth requirements of the species.

Investigation of the microbial metabolism of carbon dioxide and hydrogen in the kangaroo foregut by stable isotope probing

Kangaroos ferment forage material in an enlarged forestomach analogous to the rumen, but in contrast to ruminants, they produce little or no methane. The objective of this study was to identify the dominant organisms and pathways involved in hydrogenotrophy in the kangaroo forestomach, with the broader aim of understanding how these processes are able to predominate over methanogenesis. Stable isotope analysis of fermentation end products and RNA stable isotope probing (RNA-SIP) were used to investigate the organisms and biochemical pathways involved in the metabolism of hydrogen and carbon dioxide in the kangaroo forestomach. Our results clearly demonstrate that the activity of bacterial reductive acetogens is a key factor in the reduced methane output of kangaroos. In in vitro fermentations, the microbial community of the kangaroo foregut produced very little methane, but produced a significantly greater proportion of acetate derived from carbon dioxide than the microbial community of the bovine rumen. A bacterial operational taxonomic unit closely related to the known reductive acetogen Blautia coccoides was found to be associated with carbon dioxide and hydrogen metabolism in the kangaroo foregut. Other bacterial taxa including members of the genera Prevotella, Oscillibacter and Streptococcus that have not previously been reported as containing hydrogenotrophic organisms were also significantly associated with metabolism of hydrogen and carbon dioxide in the kangaroo forestomach.

A Phylogenomic View of Ecological Specialization in the Lachnospiraceae, a Family of Digestive Tract-Associated Bacteria

Several bacterial families are known to be highly abundant within the human microbiome, but their ecological roles and evolutionary histories have yet to be investigated in depth. One such family, Lachnospiraceae (phylum Firmicutes, class Clostridia) is abundant in the digestive tracts of many mammals and relatively rare elsewhere. Members of this family have been linked to obesity and protection from colon cancer in humans, mainly due to the association of many species within the group with the production of butyric acid, a substance that is important for both microbial and host epithelial cell growth. We examined the genomes of 30 Lachnospiraceae isolates to better understand the origin of butyric acid capabilities and other ecological adaptations within this group. Butyric acid production-related genes were detected in fewer than half of the examined genomes with the distribution of this function likely arising in part from lateral gene transfer (LGT). An investigation of environment-specific functional signatures indicated that human gut-associated Lachnospiraceae possess genes for endospore formation, whereas other members of this family lack key sporulation-associated genes, an observation supported by analysis of metagenomes from the human gut, oral cavity, and bovine rumen. Our analysis demonstrates that adaptation to an ecological niche and acquisition of defining functional roles within a microbiome can arise through a combination of both habitat-specific gene loss and LGT.