scholarly journals Muribaculaceae Genomes Assembled from Metagenomes Suggest Genetic Drivers of Differential Response to Acarbose Treatment in Mice

mSphere ◽  
2021 ◽  
Author(s):  
Byron J. Smith ◽  
Richard A. Miller ◽  
Thomas M. Schmidt
Keyword(s):  
Small Intestine ◽  
Gut Microbiome ◽  
Differential Response ◽  
Fermentation Products ◽  
Fermentation Product ◽  
The Family ◽  
Acarbose Treatment

The drug acarbose is used to treat diabetes by preventing the breakdown of starch in the small intestine, resulting in dramatic changes in the abundance of some members of the gut microbiome and its fermentation products. In mice, several of the bacteria that respond most positively are classified in the family Muribaculaceae , members of which produce propionate as a primary fermentation product.

scholarly journals Muribaculaceae genomes assembled from metagenomes suggest genetic drivers of differential response to acarbose treatment in mice

2020 ◽  
Author(s):  
Byron J. Smith ◽  
Richard A. Miller ◽  
Thomas M. Schmidt
Keyword(s):  
Small Intestine ◽  
Short Chain Fatty Acids ◽  
Ecological Niches ◽  
Gut Health ◽  
Fermentation Products ◽  
Starch Fermentation ◽  
The Family ◽  
Acarbose Treatment ◽  
Genes Encoding ◽  
Study Sites

AbstractThe drug acarbose (ACA) is used to treat diabetes, and, by inhibiting α-amylase in the small intestine, increases the amount of starch entering the lower digestive tract. This results in changes to the composition of the microbiota and their fermentation products. Acarbose also increases longevity in mice, an effect that has been correlated with increased production of the short-chain fatty acids propionate and butyrate. In experiments replicated across three study sites, two distantly related species in the bacterial family Muribaculaceae were dramatically more abundant in ACA-treated mice, distinguishing these responders from other members of the family. Bacteria in the family Muribaculaceae are predicted to produce propionate as a fermentation end product and are abundant and diverse in the guts of mice, although few isolates are available. We reconstructed genomes from metagenomes (MAGs) for nine populations of Muribaculaceae to examine factors that distinguish species that respond positively to acarbose. We found two closely related MAGs (B1A and B1B) from one responsive species that both contain a polysaccharide utilization locus with a predicted extracellular α-amylase. These genomes also shared a periplasmic neopullulanase with another, distantly related MAG (B2) representative of the only other responsive species. This gene differentiated these three MAGs from MAGs representative of non-responding species. Differential gene content in B1A and B1B may be associated with the inconsistent response of this species to acarbose across study sites. This work demonstrates the utility of culture-free genomics for inferring the ecological roles of gut bacteria including their response to pharmaceutical perturbations.ImportanceThe drug acarbose is used to treat diabetes by preventing the breakdown of starch in the small intestine, resulting in dramatic changes in the abundance of some members of the gut microbiome and its fermentation products. In mice, several of the bacteria that respond most positively are classified in the family Muribaculaceae, members of which produce propionate as a primary fermentation product. Propionate has been associated with gut health and increased longevity in mice. We found that genomes of the most responsive Muribaculaceae showed signs of specialization for starch fermentation, presumably providing them a competitive advantage in the large intestine of animals consuming acarbose. Comparisons among genomes enhance existing models for the ecological niches occupied by members of this family. In addition, genes encoding one type of enzyme known to participate in starch breakdown were found in all three genomes from responding species, but none of the other genomes.

scholarly journals Food Starch Structure Impacts Gut Microbiome Composition

mSphere ◽  
2018 ◽  
Vol 3 (3) ◽  
Author(s):  
Frederick J. Warren ◽  
Naoki M. Fukuma ◽  
Deirdre Mikkelsen ◽  
Bernadine M. Flanagan ◽  
Barbara A. Williams ◽  
...  
Keyword(s):  
Small Intestine ◽  
Microbial Community ◽  
Gut Microbiome ◽  
Nutritive Value ◽  
Human Diet ◽  
Fermentation Products ◽  
Microbiome Composition ◽  
Starch Fermentation ◽  
Starch Structure

ABSTRACT Starch is a major source of energy in the human diet and is consumed in diverse forms. Resistant starch (RS) escapes small intestinal digestion and is fermented in the colon by the resident microbiota, with beneficial impacts on colonic function and host health, but the impacts of the micro- and nanoscale structure of different physical forms of food starch on the broader microbial community have not been described previously. Here, we use a porcine in vitro fermentation model to establish that starch structure dramatically impacts microbiome composition, including the key amylolytic species, and markedly alters both digestion kinetics and fermentation outcomes. We show that three characteristic food forms of starch that survive digestion in the small intestine each give rise to substantial and distinct changes in the microbiome and in fermentation products. Our results highlight the complexity of starch fermentation processes and indicate that not all forms of RS in foods are degraded or fermented in the same way. This work points the way for the design of RS with tailored degradation by defined microbial communities, informed by an understanding of how substrate structure influences the gut microbiome, to improve nutritive value and/or health benefits. IMPORTANCE Dietary starch is a major component in the human diet. A proportion of the starch in our diet escapes digestion in the small intestine and is fermented in the colon. In this study, we use a model of the colon, seeded with porcine feces, in which we investigate the fermentation of a variety of starches with structures typical of those found in foods. We show that the microbial community changes over time in our model colon are highly dependent on the structure of the substrate and how accessible the starch is to colonic microbes. These findings have important implications for how we classify starches reaching the colon and for the design of foods with improved nutritional properties.

A curious case of nematode parasitism in a West African Hadada, Gevonticus hagedash

1945 ◽  
Vol 21 (2-3) ◽  
pp. 99-103 ◽  
Author(s):  
Phyllis A. Clapham
Keyword(s):  
Small Intestine ◽  
West Africa ◽  
West Coast ◽  
West African ◽  
The West ◽  
The Family ◽  
Nematode Parasitism

In the following article is described an interesting parasitic condition which is difficult to interpret. The small intestine of an Hadada, Geronticus hagedash, was brought back from the West Coast of Africa by Major T. A. Cockburn, M.D., R.A.M.C, who kindly passed it to me for further examination. The bird is a member of the family Plataleidae, living in wooded districts in West Africa in the neighbourhood of water and feeding on invertebrates, mainly annelids and small crustaceans which it finds at the bottom of ponds and streams in the mud.

On the Anatomy of the Trematode Petasiger exaeretus Dietz 1909, from the Intestine of Phalacrocorax Carbo

Parasitology ◽  
1934 ◽  
Vol 26 (1) ◽  
pp. 133-137 ◽  
Author(s):  
Evan Davies
Keyword(s):  
Small Intestine ◽  
Type Species ◽  
Detailed Account ◽  
Serial Sections ◽  
Phalacrocorax Carbo ◽  
The Family ◽  
Whole Mounts

The genus Petasiger which belongs to the family Echinostomidae was proposed by Dietz in 1909, with Petasiger exaeretus as the type species. The description given by Dietz of this species is incomplete and it is proposed therefore to present below a more detailed account of the anatomy, based on an examination of whole mounts and serial sections. The material was obtained from the small intestine of cormorants shot on the coast of Cardigan Bay between Aberystwyth and Llanrhystyd. Five cormorants were shot in July, and of these two contained a large number of Petasiger exaeretus in the small intestine.

scholarly journals 11β-hydroxysteroid dehydrogenase-1 deficiency alters the gut microbiome response to Western diet

2017 ◽  
Vol 232 (2) ◽  
pp. 273-283 ◽  
Author(s):  
Jethro S Johnson ◽  
Monica N Opiyo ◽  
Marian Thomson ◽  
Karim Gharbi ◽  
Jonathan R Seckl ◽  
...  
Keyword(s):  
Relative Abundance ◽  
Gut Microbiome ◽  
Inflammatory Responses ◽  
Hydroxysteroid Dehydrogenase ◽  
Western Diet ◽  
Metabolic Effects ◽  
Chow Diet ◽  
The Family ◽  
The Impact

The enzyme 11β-hydroxysteroid dehydrogenase (11β-HSD) interconverts active glucocorticoids and their intrinsically inert 11-keto forms. The type 1 isozyme, 11β-HSD1, predominantly reactivates glucocorticoids in vivo and can also metabolise bile acids. 11β-HSD1-deficient mice show altered inflammatory responses and are protected against the adverse metabolic effects of a high-fat diet. However, the impact of 11β-HSD1 on the composition of the gut microbiome has not previously been investigated. We used high-throughput 16S rDNA amplicon sequencing to characterise the gut microbiome of 11β-HSD1-deficient and C57Bl/6 control mice, fed either a standard chow diet or a cholesterol- and fat-enriched ‘Western’ diet. 11β-HSD1 deficiency significantly altered the composition of the gut microbiome, and did so in a diet-specific manner. On a Western diet, 11β-HSD1 deficiency increased the relative abundance of the family Bacteroidaceae, and on a chow diet, it altered relative abundance of the family Prevotellaceae. Our results demonstrate that (i) genetic effects on host–microbiome interactions can depend upon diet and (ii) that alterations in the composition of the gut microbiome may contribute to the aspects of the metabolic and/or inflammatory phenotype observed with 11β-HSD1 deficiency.

Notes on New Aspidogastrid Species, with a Consideration of the Phylogeny of the Group

Parasitology ◽  
1936 ◽  
Vol 28 (4) ◽  
pp. 487-501 ◽  
Author(s):  
Ernest Carroll Faust ◽  
Chung-Chang Tang
Keyword(s):  
Small Intestine ◽  
New Species ◽  
New Family ◽  
Spiral Valve ◽  
New Subgenus ◽  
The Family ◽  
A New Species

1. Cotylaspis sinensis and Lophotaspis orientalis are described as new species of trematodes from the small intestine of the turtle, Amyda tuberculata, from Foochow, Fukien Province, China.2. Stichocotyle cristata is described as a new species from the spiral valve of the cow-nosed ray, Rhinoptera quadriloba, from Biloxi Bay, Mississippi.3. A new subgenus, Multicalyx, is created for the species Stichocotyle cristata, while the species S. nephropis appropriately belongs to a new subgenus Stichocotyle.4. Evidence is provided that aspidogastrid worms are referable neither to the Monogenea nor the Digenea, but belong to an intermediate subclass group, Aspidogastrea, n.n.5. The genus Stichocotyle has been removed from the family Aspidogastridae Poche, 1907, and placed in a new family, Stichocotylidae.

A new species of Neoascaris from Rattus assimilis, with a redefinition of the genus

Parasitology ◽  
1957 ◽  
Vol 47 (3-4) ◽  
pp. 350-360 ◽  
Author(s):  
J. F. A. Sprent
Keyword(s):  
Small Intestine ◽  
New Species ◽  
Ventral Surface ◽  
Unequal Distribution ◽  
Oesophageal Gland ◽  
The Family ◽  
Primitive Species ◽  
A New Species

Neoascaris mackerrasae from the small intestine of the Australian allied rat (Rattus assimilis) is described. It is compared with Neoascaris vitulorum and found to differ as follows:(1) It is a considerably smaller species.(2) The vulva is situated more posteriorly.(3) The nucleus of the dorsal oesophageal gland is oval and situated in the dorsal sector of the ventriculus, whereas in N. vitulorum it is elongate and is situated in the sub ventral sectors.(4) The eggs are more coarsely pitted.(5) The spicules have two flanges which form a gutter on the ventral surface, whereas in N. vitulorum they are almost cylindrical.The genus Neoascaris is redefined so as to include the presence of rudimentary cervical alae and the unequal distribution of the oesophageal glands. The genus is placed in the family Toxocaridae Hartwich, 1954.Other ascaridoid parasites occurring in rodents are listed and differentiated from N. mackerrasae. It is suggested that on account of the arrangement in the ventriculus of the nuclei of the oesophageal glands, N. mackerrasae may represent a primitive species among the ascaridoid parasites of mammals.

scholarly journals Mangroviflexus xiamenensis gen. nov., sp. nov., a member of the family Marinilabiliaceae isolated from mangrove sediment

2012 ◽  
Vol 62 (Pt_8) ◽  
pp. 1819-1824 ◽  
Author(s):  
Chao Zhao ◽  
Zhaoming Gao ◽  
Qiwei Qin ◽  
Lingwei Ruan
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Phylogenetic Analyses ◽  
Mangrove Sediment ◽  
Rrna Gene ◽  
Major Polar Lipid ◽  
Fermentation Products ◽  
Content Type ◽  
Link Type ◽  
The Family

A Gram-negative, obligately anaerobic, non-spore-forming, long rod-shaped bacterium strain P2T was isolated from the offshore mangrove sediment of the South China Sea. Growth was observed at between 22 and 39 °C, with an optimum at 35 °C. The pH range for growth was 5.0–8.5, with an optimum around pH 7.0–7.5. Salt tolerance was determined between 0.2 and 3.5 % (w/v), optimum at 0.5–1.0 %. Catalase and oxidase activities were negative. Strain P2T utilized cysteine, lactate, pyruvate, yeast extract or H2/CO2+acetate as electron donors, and sulfate or sulfite as electron acceptors. Metabolism was strictly fermentative. The main organic fermentation products were propionate, acetate and succinate. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain P2T formed a distinct evolutionary lineage within the family Marinilabiliaceae . Strain P2T was most closely related to members of the genera Alkaliflexus (92.0 % 16S rRNA gene sequence similarity), Marinilabilia (91.7 %) and Anaerophaga (89.9 %) of the family Marinilabiliaceae . The DNA G+C content of the novel strain was 44.2±1.0 mol%. The dominant fatty acids of strain P2T were iso-C15 : 0 (33.5 %), anteiso-C15 : 0 (18.9 %), C16 : 0 (5.4 %), C16 : 0 3-OH (7.7 %) and iso-C17 : 0 3-OH (13.3 %). The respiratory quinone was menaquinone 7 (100 % of total quinone) and the major polar lipid was phosphatidylethanolamine. Strain P2T was distinguishable from members of phylogenetically related genera by differences in several phenotypic properties. On the basis of phylogenetic, phenotypic and physiological evidence, a novel genus, Mangroviflexus, is proposed to harbour strain P2T ( = CGMCC 1.5167T = DSM 24214T) which is described as the type strain of a novel species, Mangroviflexus xiamenensis gen. nov., sp. nov.

Enhancing Antioxidant Activity of Soluble Polysaccharide from the Submerged Fermentation Product of Cordyceps sinensis by Using Cellulase

2013 ◽  
Vol 641-642 ◽  
pp. 975-978 ◽  
Author(s):  
Xiao Lei Li ◽  
Dan Li
Keyword(s):  
Antioxidant Activity ◽  
Free Radicals ◽  
Submerged Fermentation ◽  
Untreated Control ◽  
Reducing Power ◽  
Cordyceps Sinensis ◽  
Fermentation Products ◽  
Fermentation Product ◽  
Soluble Polysaccharide ◽  
Free Radicals Scavenging

Soluble polysaccharide is a main bioactive composition of Cordyceps sinensis. To increase its antioxidant activity, 500 mg of submerged fermentation products of C. sinensis was incubated with 7.5 U or 375 U of cellulase in 50 mL of water at 50°C for 2 h. The content of soluble polysaccharide of submerged fermentation products of C. sinensis increased from 30.28% to 33.23~38.10%. At the same concentration, the DPPH free radicals scavenging capability and reducing power of cellulase-treated soluble polysaccharide were higher than those of untreated control.

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