BackgroundCampylobacters are an unwelcome member of the poultry gut microbiota in terms of food safety. The objective of this study was to compare the microbiota, inflammatory responses, and zootechnical parameters of broiler chickens not exposed to Campylobacter jejuni with those exposed either early at 6 days old or at the age commercial broiler chicken flocks are frequently observed to become colonized at 20 days old.ResultsBirds infected with Campylobacter at 20 days became cecal colonized within 2 days of exposure, whereas birds infected at 6 days of age did not show complete colonization of the sample cohort until 9 days post-infection. All birds sampled thereafter were colonized until the end of the study at 35 days (mean 6.1 log10 CFU per g of cecal contents). The cecal microbiota of birds infected with Campylobacter were significantly different to age-matched non-infected controls at 2 days post-infection, but generally, the composition of the cecal microbiota were more affected by bird age as the time post infection increased. The effects of Campylobacter colonization on the cecal microbiota were associated with reductions in the relative abundance of OTUs within the taxonomic family Lactobacillaceae and the Clostridium cluster XIVa. Specific members of the Lachnospiraceae and Ruminococcaceae families exhibit transient shifts in microbial community populations dependent upon the age at which the birds become colonized by C. jejuni. Analysis of ileal and cecal chemokine/cytokine gene expression revealed increases in IL-6, IL-17A, and Il-17F consistent with a Th17 response, but the persistence of the response was dependent on the stage/time of C. jejuni colonization that coincide with significant reductions in the abundance of Clostridium cluster XIVa.ConclusionsThis study combines microbiome data, cytokine/chemokine gene expression with intestinal villus, and crypt measurements to compare chickens colonized early or late in the rearing cycle to provide insights into the process and outcomes of Campylobacter colonization. Early colonization results in a transient growth rate reduction and pro-inflammatory response but persistent modification of the cecal microbiota. Late colonization produces pro-inflammatory responses with changes in the cecal microbiota that will endure in market-ready chickens.Electronic supplementary materialThe online version of this article (10.1186/s40168-018-0477-5) contains supplementary material, which is available to authorized users.
An esterase was isolated from cultures of the filamentous fungus Penicillium funiculosum grown on sugar beet pulp as the sole carbon source. The enzyme (ferulic acid esterase B, FAEB) was shown to be a cinnamoyl esterase (CE), efficiently releasing hydroxycinnamic acids from synthetic ester substrates and plant cell walls, and bound strongly to microcrystalline cellulose. A gene fragment was obtained by PCR using partial amino-acid sequences obtained from the pure enzyme and used to a probe a P. funiculosum genomic DNA library. A clone containing a 1120-bp ORF, faeB, was obtained which encoded a putative 353-residue preprotein including an 18-residue signal peptide, which when expressed in Eschericia coli produced CE activity. Northern analysis showed that transcription of faeB was tightly regulated, being stimulated by growth of the fungus on sugar beet pulp but inhibited by free glucose. The faeB promoter sequence contains putative motifs for binding an activator protein, XLNR, and a carbon catabolite repressor protein, CREA. FAEB was comprised of two distinct domains separated by a 20 residue Thr/Ser/Pro linker region. The N-terminal domain comprised 276 amino acids, contained a G-X-S-X-G motif typical of serine esterases, and was shown to be a member of a family comprising serine esterases, including microbial acetyl xylan esterases, poly (3-hydroxyalkanoate) depolymerases and CEs, and proteins of unknown function from Mycobacterium spp. and plants. The C-terminal domain comprised 39 amino acids and closely resembled the family 1 cellulose binding carbohydrate-binding modules (CBM) of fungal glycosyl hydrolases. This is the first report of a fungal CE with a CBM.Keywords: Feruloyl esterase; cinnamoyl esterase; carbohydrate binding module; Penicillium funiculosum; ferulic acid.Plant cell walls are comprised of a heterogeneous mixture of polymers including cellulose and hemicellulose (e.g. arabinoxylans, pectins, galactomannans, b-glucans) and their biodegradation is a key component in the global cycling of photosynthetically fixed carbon. Hydroxycinnamates are increasingly recognized as important components in determining the physical and chemical properties of plant cell walls. Ferulates and p-coumarates are linked to cell wall polysaccharides through ester bonds (135 to arabinofuranose residues in heteroxylans of Graminaceous monocots such as wheat, barley, maize; 132 to arabinofuranose residues or 136 to galactopyranose residues in the pectins of Caryophylaceous dicots such as sugar beet and spinach). There is evidence to suggest that both the monomeric forms (e.g. ferulate and p-coumarate) and the various dehydrodimers (e.g. 5±5 diferulate) may act as nucleation sites during lignification in the latter stages of wall development [1], and it has been established that ferulates and p-coumarates are linked to lignin through ester and/or ether linkages [1±4]. There is also speculation that hydroxycinnamates serve to link cell wall proteins with other structural polymers. The presence of ferulates and dehydrod...
The territorial marking fluid of the male Bengal tiger, Panthera tigris, consists of a mixture of urine and a small quantity of lipid material that may act as a controlled-release carrier for the volatile constituents of the fluid. Using gas chromatography and gas chromatography-mass spectrometry, 98 volatile compounds and elemental sulfur were identified in the marking fluid. Another 16 volatiles were tentatively identified. The majority of these compounds were alkanols, alkanals, 2-alkanones, branched and unbranched alkanoic acids, dimethyl esters of dicarboxylic acids, γ-and δ-lactones, and compounds containing nitrogen or sulfur. Several samples of the marking fluid contained pure (R)-3-methyl-2-octanone, (R)-3-methyl-2-nonanone, and (R)-3-methyl-2-decanone, but these ketones were partly or completely racemized in other samples. The γ-lactone (S)-(+)-(Z)-6-dodecen-4-olide and the C8 to C16 saturated (R)-γ-lactones and (S)-δ-lactones were present in high enantiomeric purities.The chiral carboxylic acids, 2-methylnonanoic acid, 2-methyldecanoic acid, 2-methylundecanoic acid, and 2-ethylhexanoic acid were racemates. Cadaverine, putrescine, and 2-acetylpyrroline, previously reported as constituents of tiger urine, were not detected. The dominant contribution of some ketones, fatty acids, and lactones to the composition of the headspace of the marking fluid suggests that these compounds may be important constituents of the pheromone. Although it constitutes only a small proportion, the lipid fraction of the fluid contained larger quantities of the volatile organic compounds than the aqueous fraction (urine). The lipid derives its role as controlled-release carrier of the chemical message left by the tiger, from its affinity for the volatiles of the marking fluid. Six proteins with masses ranging from 16 to 69 kDa, inter alia, the carboxylesteraselike urinary protein known as cauxin, previously identified in the urine of the domestic cat and other felid species, were identified in the urine fraction of the marking fluid.
Improvements in growth performance and health are key goals in broiler chicken production. Inclusion of prebiotic galacto-oligosaccharides (GOS) in broiler feed enhanced the growth rate and feed conversion of chickens relative to those obtained with a calorie-matched control diet. Comparison of the cecal microbiota identified key differences in abundances of Lactobacillus spp. Increased levels of Lactobacillus johnsonii in GOS-fed juvenile birds at the expense of Lactobacillus crispatus were linked to improved performance (growth rate and market weight). Investigation of the innate immune responses highlighted increases of ileal and cecal interleukin-17A (IL-17A) gene expression counterposed to a decrease in IL-10. Quantification of the autochthonous Lactobacillus spp. revealed a correlation between bird performance and L. johnsonii abundance. Shifts in the cecal populations of key Lactobacillus spp. of juvenile birds primed intestinal innate immunity without harmful pathogen challenge. IMPORTANCE Improvements in the growth rate of broiler chickens can be achieved through dietary manipulation of the naturally occurring bacterial populations while mitigating the withdrawal of antibiotic growth promoters. Prebiotic galacto-oligosaccharides (GOS) are manufactured as a by-product of dairy cheese production and can be incorporated into the diets of juvenile chickens to improve their health and performance. This study investigated the key mechanisms behind this progression and pinpointed L. johnsonii as a key species that facilitates the enhancements in growth rate and gut health. The study identified the relationships between the GOS diet, L. johnsonii intestinal populations, and cytokine immune effectors to improve growth.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.