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Journal of the Formosan Medical... Jan 2021Rosacea has been linked to inflammatory bowel disease and small bowel bacterial overgrowth. We aimed to investigate the fecal microbial profiling and the potential gene...
BACKGROUND/PURPOSE
Rosacea has been linked to inflammatory bowel disease and small bowel bacterial overgrowth. We aimed to investigate the fecal microbial profiling and the potential gene functions between rosacea and non-rosacea subjects.
METHODS
A case-control study. Fecal microbiome and predicted genetic function inferred from high-throughput 16S ribosomal RNA sequencing were analyzed between rosacea (n = 11) and age-, gender- and body mass index-matched non-rosacea subjects (n=110). The correlation between altered microbiome as well as lifestyle and diet were also investigated.
RESULTS
A significant reduction of fecal microbial richness was found in rosacea patients. A distinct fecal microbial community structure was demonstrated in rosacea patients. The discriminating enriched genera in rosacea patients included Rhabdochlamydia, CF231, Bifidobacterium, Sarcina, Ruminococcus, belonging to the phylum of Chlamydiae, Bacteroidetes, Actinobacteria, and Lentisphaerae. The discriminating reduced abundant genera included Lactobacillus, Megasphaerae, Acidaminococcus, Hemophilus, Roseburia, Clostridium, belong to the phylum of Firmicutes; and Citrobacter, belonging to the phylum of Proteobacteria. The distinct fecal microbial composition might be related to sulfur metabolism, cobalamin, and carbohydrate transport.
CONCLUSION
An altered fecal microbial richness and composition were observed in rosacea patients. The distinct microbial composition might be related to sulfur metabolism, cobalamin and carbohydrate transport.
Topics: Case-Control Studies; Feces; Gastrointestinal Microbiome; Humans; RNA, Ribosomal, 16S; Rosacea
PubMed: 32446756
DOI: 10.1016/j.jfma.2020.04.034 -
Nature Biotechnology Aug 2017The RNA-guided endonuclease Cpf1 is a promising tool for genome editing in eukaryotic cells. However, the utility of the commonly used Acidaminococcus sp. BV3L6 Cpf1...
The RNA-guided endonuclease Cpf1 is a promising tool for genome editing in eukaryotic cells. However, the utility of the commonly used Acidaminococcus sp. BV3L6 Cpf1 (AsCpf1) and Lachnospiraceae bacterium ND2006 Cpf1 (LbCpf1) is limited by their requirement of a TTTV protospacer adjacent motif (PAM) in the DNA substrate. To address this limitation, we performed a structure-guided mutagenesis screen to increase the targeting range of Cpf1. We engineered two AsCpf1 variants carrying the mutations S542R/K607R and S542R/K548V/N552R, which recognize TYCV and TATV PAMs, respectively, with enhanced activities in vitro and in human cells. Genome-wide assessment of off-target activity using BLISS indicated that these variants retain high DNA-targeting specificity, which we further improved by introducing an additional non-PAM-interacting mutation. Introducing the identified PAM-interacting mutations at their corresponding positions in LbCpf1 similarly altered its PAM specificity. Together, these variants increase the targeting range of Cpf1 by approximately threefold in human coding sequences to one cleavage site per ∼11 bp.
Topics: Acidaminococcus; Bacterial Proteins; Endonucleases; Genetic Engineering; Genetic Variation; HEK293 Cells; Humans; Mutagenesis, Site-Directed
PubMed: 28581492
DOI: 10.1038/nbt.3900 -
Applied Microbiology and Biotechnology Jan 2019Unabsorbed copper accumulates in the hindgut of pigs that consume high levels of dietary copper, which enhances the coselection of antibiotic-resistant bacteria and is...
Unabsorbed copper accumulates in the hindgut of pigs that consume high levels of dietary copper, which enhances the coselection of antibiotic-resistant bacteria and is considered detrimental to the environment and to porcine health. In our study, a combination of 16S rRNA pyrosequencing and nontargeted metabolomics was used to investigate the microbiome-metabolome responses to dietary copper levels in the hindgut of suckling piglets. The results showed that the dietary copper level affected the abundance of several Clostridia genera and that the relative abundance of butyrate-producing bacteria, such as Coprococcus, Roseburia, and Acidaminococcus, was reduced in the 300 mg kg (high) Cu group. Metabolomic analysis revealed that dietary copper levels affected protein and carbohydrate metabolites, protein biosynthesis, the urea cycle, galactose metabolism, gluconeogenesis, and amino acid metabolism (including the metabolism of arginine, proline, β-alanine, phenylalanine, tyrosine, and methionine). Furthermore, Pearson's correlation analysis showed that the abundance levels of Coprococcus (family Lachnospiraceae) and operational taxonomic unit (OTU) 18 (family Ruminococcaceae) were positively correlated with energy metabolism pathways (gluconeogenesis, glycolysis, and the pentose phosphate pathway). The abundance of Streptococcus was negatively correlated with amino acid metabolism pathways (protein biosynthesis, glycine, serine, threonine, methionine, phenylalanine, and tyrosine metabolism), and OTU583 and OTU1067 (family Rikenellaceae) were positively correlated with amino acid metabolism pathways. These results suggest that the copper levels consumed by LC (low-copper group) versus HC (high-copper group) animals alter the composition of the gut microbiota and modulate microbial metabolic pathways, which may further affect the health of suckling piglets.
Topics: Animals; Animals, Newborn; Blood Chemical Analysis; Copper; Diet; Feces; Gas Chromatography-Mass Spectrometry; Gastrointestinal Microbiome; High-Throughput Nucleotide Sequencing; Metabolome; Metabolomics; Metagenomics; RNA, Ribosomal, 16S; Swine; Trace Elements
PubMed: 30535578
DOI: 10.1007/s00253-018-9533-0 -
MSystems Mar 2020Type 2 diabetes (T2D) is a complex metabolic syndrome characterized by insulin dysfunction and abnormalities in glucose and lipid metabolism. The gut microbiome has been...
Type 2 diabetes (T2D) is a complex metabolic syndrome characterized by insulin dysfunction and abnormalities in glucose and lipid metabolism. The gut microbiome has been recently identified as an important factor for development of T2D. In this study, a total of 102 subjects were recruited, and we have looked at the gut microbiota of prediabetics (PreDMs) ( = 17), newly diagnosed diabetics (NewDMs) ( = 11), and diabetics on antidiabetic treatment (KnownDMs) ( = 39) and compared them with healthy nondiabetics (ND) ( = 35). Twenty-five different serum biomarkers were measured to assess the status of diabetes and their association with gut microbiota. Our analysis revealed nine different genera as differentially abundant in four study groups. Among them, and were found to be significantly ( < 0.05) decreased, while was increased in NewDMs compared to ND and recovered in KnownDMs. was inversely correlated with HbA1c and positively correlated with total antioxidants. Compared to ND, there was increased abundance of , , and and decreased abundance of in KnownDMs. Among many taxa known to act as community drivers during disease progression, we observed genus as a common driver taxon among all diabetic groups. On the basis of the results of random forest analysis, we found that the genera and and that the serum metabolites fasting glucose, HbA1c, methionine, and total antioxidants were highly discriminative factors among studied groups. Taken together, our data revealed that gut microbial diversity of NewDMs but not of PreDMs is significantly different from that of ND. Interestingly, after antidiabetic treatment, the microbial diversity of KnownDMs tends to recover toward that of ND. Gut microbiota is considered to play a role in disease progression, and previous studies have reported an association of microbiome dysbiosis with T2D. In this study, we have attempted to investigate gut microbiota of ND, PreDMs, NewDMs, and KnownDMs. We found that the genera and decreased significantly ( < 0.05) in treatment-naive diabetics and were restored in KnownDMs on antidiabetic treatment. To the best of our knowledge, comparative studies on shifts in the microbial community in individuals of different diabetic states are lacking. Understanding the transition of microbiota and its association with serum biomarkers in diabetics with different disease states may pave the way for new therapeutic approaches for T2D.
PubMed: 32234773
DOI: 10.1128/mSystems.00578-19 -
ELife Aug 2019CRISPR-Cas systems provide bacteria and archaea with programmable immunity against mobile genetic elements. Evolutionary pressure by CRISPR-Cas has driven bacteriophage...
CRISPR-Cas systems provide bacteria and archaea with programmable immunity against mobile genetic elements. Evolutionary pressure by CRISPR-Cas has driven bacteriophage to evolve small protein inhibitors, anti-CRISPRs (Acrs), that block Cas enzyme function by wide-ranging mechanisms. We show here that the inhibitor AcrVA4 uses a previously undescribed strategy to recognize the Cas12a (LbCas12a) pre-crRNA processing nuclease, forming a Cas12a dimer, and allosterically inhibiting DNA binding. The Cas12a (AsCas12a) enzyme, widely used for genome editing applications, contains an ancestral helical bundle that blocks AcrVA4 binding and allows it to escape anti-CRISPR recognition. Using biochemical, microbiological, and human cell editing experiments, we show that Cas12a orthologs can be rendered either sensitive or resistant to AcrVA4 through rational structural engineering informed by evolution. Together, these findings explain a new mode of CRISPR-Cas inhibition and illustrate how structural variability in Cas effectors can drive opportunistic co-evolution of inhibitors by bacteriophage.
Topics: Acidaminococcus; Bacteriophages; CRISPR-Cas Systems; Clostridiales; Enzyme Inhibitors; Evolution, Molecular; Host-Parasite Interactions; Viral Proteins
PubMed: 31397669
DOI: 10.7554/eLife.49110 -
Applied and Environmental Microbiology Jul 1994Mixed ruminal bacteria convert trans-aconitate to tricarballylate, a tricarboxylic acid which chelates blood divalent cations and decreases their availability (J. B....
Mixed ruminal bacteria convert trans-aconitate to tricarballylate, a tricarboxylic acid which chelates blood divalent cations and decreases their availability (J. B. Russell and P. J. Van Soest, Appl. Environ. Microbiol. 47:155-159, 1984). Decreases in blood magnesium in turn cause a potentially fatal disease known as grass tetany. trans-Aconitate was stoichiometrically reduced to tricarballylate by Selenomonas ruminantium, a common ruminal bacterium in grass-fed ruminants (J. B. Russell, Appl. Environ. Microbiol. 49:120-126, 1985). When mixed ruminal bacteria were enriched with trans-aconitate, a trans-aconitate-oxidizing bacterium was also isolated (G. M. Cook, F. A. Rainey, G. Chen, E. Stackebrandt, and J. B. Russell, Int. J. Syst. Bacteriol. 44:576-578, 1994). The trans-aconitate-oxidizing bacterium was identified as Acidaminococcus fermentans, and it converted trans-aconitate to acetate, a nontoxic end product of ruminal fermentation. When S. ruminantium and A. fermentans were cocultured with trans-aconitate and glucose, tricarballylate never accumulated and all the trans-aconitate was converted to acetate. Continuous-culture studies (dilution rate, 0.1 h-1) likewise indicated that A. fermentans could outcompete S. ruminantium for trans-aconitate. When mixed ruminal bacteria were incubated in vitro with 10 mM trans-aconitate for 24 h, 45% of the trans-aconitate was converted to tricarballylate. Tricarballylate production decreased 50% if even small amounts of A. fermentans were added to the incubation mixes (0.01 mg of protein per mg of mixed bacterial protein). When A. fermentans (2 g of bacterial protein) was added directly to the rumen, the subsequent conversion of trans-aconitate to tricarballylate decreased 50%, but this effect did not persist for more than 18 h.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Aconitic Acid; Animals; Cattle; Cattle Diseases; Female; Fermentation; Gram-Negative Anaerobic Bacteria; In Vitro Techniques; Oxidation-Reduction; Poaceae; Rumen; Tetany; Tricarboxylic Acids; Veillonellaceae
PubMed: 8074529
DOI: 10.1128/aem.60.7.2533-2537.1994 -
Frontiers in Microbiology 2016Understanding the relationship between ingested plant material and the attached microbiome is essential for developing methodologies to improve ruminant nutrient use...
Understanding the relationship between ingested plant material and the attached microbiome is essential for developing methodologies to improve ruminant nutrient use efficiency. We have previously shown that perennial ryegrass (PRG) rumen bacterial colonization events follow a primary (up to 4 h) and secondary (after 4 h) pattern based on the differences in diversity of the attached bacteria. In this study, we investigated temporal niche specialization of primary and secondary populations of attached rumen microbiota using metagenomic shotgun sequencing as well as monitoring changes in the plant chemistry using mid-infrared spectroscopy (FT-IR). Metagenomic Rapid Annotation using Subsystem Technology (MG-RAST) taxonomical analysis of shotgun metagenomic sequences showed that the genera , and dominated the attached microbiome irrespective of time. MG-RAST also showed that , and rDNA increased in read abundance during secondary colonization, whilst decreased in read abundance. MG-RAST Clusters of Orthologous Groups (COG) functional analysis also showed that the primary function of the attached microbiome was categorized broadly within "metabolism;" predominantly amino acid, carbohydrate, and lipid metabolism and transport. Most sequence read abundances (51.6, 43.8, and 50.0% of COG families pertaining to amino acid, carbohydrate and lipid metabolism, respectively) within these categories were higher in abundance during secondary colonization. Kyoto encyclopedia of genes and genomes (KEGG) pathways analysis confirmed that the PRG-attached microbiota present at 1 and 4 h of rumen incubation possess a similar functional capacity, with only a few pathways being uniquely found in only one incubation time point only. FT-IR data for the plant residues also showed that the main changes in plant chemistry between primary and secondary colonization was due to increased carbohydrate, amino acid, and lipid metabolism. This study confirmed primary and secondary colonization events and supported the hypothesis that functional changes occurred as a consequence of taxonomical changes. Sequences within the carbohydrate metabolism COG families contained only 3.2% of cellulose activities, on average across both incubation times (1 and 4 h), suggesting that degradation of the plant cell walls may be a key rate-limiting factor in ensuring the bioavailability of intra-plant nutrients in a timely manner to the microbes and ultimately the animal. This suggests that a future focus for improving ruminant nutrient use efficiency should be altering the recalcitrant plant cell wall components and/or improving the cellulolytic capacity of the rumen microbiota.
PubMed: 27917166
DOI: 10.3389/fmicb.2016.01854 -
Nature Communications Aug 2019Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the CFTR gene. The 3272-26A>G and 3849+10kbC>T CFTR mutations alter the correct splicing...
Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the CFTR gene. The 3272-26A>G and 3849+10kbC>T CFTR mutations alter the correct splicing of the CFTR gene, generating new acceptor and donor splice sites respectively. Here we develop a genome editing approach to permanently correct these genetic defects, using a single crRNA and the Acidaminococcus sp. BV3L6, AsCas12a. This genetic repair strategy is highly precise, showing very strong discrimination between the wild-type and mutant sequence and a complete absence of detectable off-targets. The efficacy of this gene correction strategy is verified in intestinal organoids and airway epithelial cells derived from CF patients carrying the 3272-26A>G or 3849+10kbC>T mutations, showing efficient repair and complete functional recovery of the CFTR channel. These results demonstrate that allele-specific genome editing with AsCas12a can correct aberrant CFTR splicing mutations, paving the way for a permanent splicing correction in genetic diseases.
Topics: Acidaminococcus; Alleles; Bacterial Proteins; Biopsy; CRISPR-Associated Proteins; Cell Culture Techniques; Cell Line; Cystic Fibrosis; Cystic Fibrosis Transmembrane Conductance Regulator; Endonucleases; Gene Editing; Humans; Intestines; Organoids; Point Mutation; RNA Splice Sites; RNA Splicing
PubMed: 31391465
DOI: 10.1038/s41467-019-11454-9 -
Applied and Environmental Microbiology Jul 1994Acidaminococcus fermentans utilized citrate or the citrate analog aconitate as an energy source for growth, and these tricarboxylates were used simultaneously. Citrate...
Acidaminococcus fermentans utilized citrate or the citrate analog aconitate as an energy source for growth, and these tricarboxylates were used simultaneously. Citrate utilization and uptake showed biphasic kinetics. High-affinity citrate uptake had a K(t) of 40 muM, but the V(max) was only 25 nmol/mg of protein per min. Low-affinity citrate utilization had a 10-fold higher V(max), but the K(s) was greater than 1.0 mM. Aconitate was a competitive inhibitor (K(i) = 34muM) of high-affinity citrate uptake, but low-affinity aconitate utilization had a 10-fold-lower requirement for sodium than did low-affinity citrate utilization. On the basis of this large difference in sodium requirements, it appeared that A. fermentans probably has two systems of tricarboxylate uptake: (i) a citrate/aconitate carrier with a low affinity for sodium and (ii) an aconitate carrier with a high affinity for sodium. Citrate was catabolized by a pathway involving a biotin-requiring, avidin-sensitive, sodium-dependent, membrane-bound oxaloacetate decarboxylase. The cells also had aconitase, but this enzyme was unable to convert citrate to isocitrate. Since cell-free extracts converted either aconitate or glutamate to 2-oxoglutarate, it appeared that aconitate was being catabolized by the glutaconyl-CoA decarboxylase pathway. Exponentially growing cultures on citrate or citrate plus aconitate were inhibited by the sodium/proton antiporter, monensin. Because monensin had no effect on cultures growing with aconitate alone, it appeared that citrate metabolism was acting as an inducer of monensin sensitivity. A. fermentans cells always had a low proton motive force (<50 mV), and cells treated with the protonophore TCS (3,3',4',5-tetrachlorosalicylanide) grew even though the proton motive force was less than 20 mV. On the basis of these results, it appeared that A. fermentans was depending almost exclusively on a sodium motive force for its membrane energetics.
PubMed: 16349331
DOI: 10.1128/aem.60.7.2538-2544.1994 -
Applied Microbiology and Biotechnology Apr 2024The rumen microbiota is important for energy and nutrient acquisition in cattle, and therefore its composition may also affect carcass merit and meat quality attributes....
The rumen microbiota is important for energy and nutrient acquisition in cattle, and therefore its composition may also affect carcass merit and meat quality attributes. In this study, we examined the associations between archaeal and bacterial taxa in the rumen microbiota of beef cattle and 12 different attributes, including hot carcass weight (HCW), dressing percentage, ribeye area (REA), intramuscular fat content, marbling score, fat thickness, yield grade, moisture content, purge loss, and shear force. There were significant correlations between the relative abundance of certain archaeal and bacterial genera and these attributes. Notably, Selenomonas spp. were positively correlated with live weight and HCW, while also being negatively correlated with purge loss. Members of the Christensenellaceae R-7, Moryella, and Prevotella genera exhibited positive and significant correlations with various attributes, such as dressing percentage and intramuscular fat content. Ruminococcaceae UCG-001 was negatively correlated with live weight, HCW, and dressing percentage, while Acidaminococcus and Succinivibrionaceae UCG-001 were negatively correlated with intramuscular fat content, moisture content, and marbling score. Overall, our findings suggest that specific changes in the rumen microbiota could be a valuable tool to improve beef carcass merit and meat quality attributes. Additional research is required to better understand the relationship between the rumen microbiota and these attributes, with the potential to develop microbiome-targeted strategies for enhancing beef production. KEY POINTS: • Certain rumen bacteria were associated with carcass merit and meat quality • Moryella was positively correlated with intramuscular fat in beef carcasses • Acidaminococcus spp. was negatively correlated with marbling and intramuscular fat.
Topics: Cattle; Animals; Body Composition; Rumen; Meat; Microbiota; Bacteria; Archaea
PubMed: 38581592
DOI: 10.1007/s00253-024-13126-1