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International Journal of Molecular... Sep 2023The pyruvate dehydrogenase complex regulator (PdhR) was originally identified as a repressor of the operon, which encodes the pyruvate dehydrogenase complex (PDHc) and...
The pyruvate dehydrogenase complex regulator (PdhR) was originally identified as a repressor of the operon, which encodes the pyruvate dehydrogenase complex (PDHc) and PdhR itself. According to previous reports, PdhR plays a regulatory role in the physiological and metabolic pathways of bacteria. At present, the function of PdhR in is still poorly understood. In this study, RNA sequencing (RNA-Seq) of the wild-type strain and the Δ mutant strains was performed for comparison to identify the PdhR-controlled pathways, revealing that PdhR regulates ~7.38% of the transcriptome. We found that the deletion of resulted in the downregulation of practically all polar and lateral flagella genes in ; meanwhile, motility assay and transmission electron microscopy (TEM) confirmed that the Δ mutant was non-motile and lacked flagella. Moreover, the results of RNA-seq and quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) showed that PdhR positively regulated the expression of the T3SS cluster, and the Δ mutant significantly reduced the ability of to infect Caco-2 cells compared with the WT. Consistent with previous research, pyruvate-sensing PdhR directly binds to its promoter and inhibits -- operon expression. In addition, we identified two additional downstream genes, and , that are directly negatively regulated by PdhR. Furthermore, we also demonstrated that ArcA was identified as being located upstream of and and directly negatively regulating their expression. Overall, we revealed the function and regulatory pathway of PdhR, which will allow for a more in-depth investigation into pathogenicity as well as the complex regulatory network.
Topics: Humans; Pyruvate Dehydrogenase Complex; Escherichia coli Proteins; Plesiomonas; Escherichia coli; Repressor Proteins; Caco-2 Cells; Gene Expression Profiling
PubMed: 37833920
DOI: 10.3390/ijms241914473 -
Fish Physiology and Biochemistry Dec 2023The primary organ for absorbing dietary fat is the gut. High dietary lipid intake negatively affects health and absorption by causing fat deposition in the intestine....
The primary organ for absorbing dietary fat is the gut. High dietary lipid intake negatively affects health and absorption by causing fat deposition in the intestine. This research explores the effect of a high-fat diet (HFD) on intestinal microbiota and its connections with endoplasmic reticulum stress and inflammation. 60 fish (average weight: 45.84 ± 0.07 g) were randomly fed a control diet (6% fat) and a high-fat diet (12 % fat) in four replicates for 12 weeks. From the result, hepatosomatic index (HSI), Visceralsomatic index (VSI), abdominal fat (ADF), Intestosomatic index (ISI), mesenteric fat (MFI), Triglycerides (TG), total cholesterol (TC), non-esterified fatty acid (NEFA) content were substantially greater on HFD compared to the control diet. Moreover, fish provided the HFD significantly obtained lower superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities. In contrast, an opposite result was seen in malondialdehyde (MDA) content in comparison to the control. HFD significantly altered intestinal microbiota in blunt snout bream, characterized by an increased abundance of Aeromonas, Plesiomonas proteobacteria, and firmicutes with a reduced abundance of Cetobacterium and ZOR0006. The transcriptional levels of glucose-regulated protein 78 (grp78), inositol requiring enzyme 1 (ire1), spliced X box-binding protein 1 (xbp1), DnaJ heat shock protein family (Hsp40) member B9 (dnajb9), tumor necrosis factor alpha (tnf-α), nuclear factor-kappa B (nf-κb), monocyte chemoattractant protein-1 (mcp-1), and interleukin-6 (il-6) in the intestine were markedly upregulated in fish fed HFD than the control group. Also, the outcome was similar in bax, caspases-3, and caspases-9, ZO-1, Occludin-1, and Occludin-2 expressions. In conclusion, HFD could alter microbiota and facilitate chronic inflammatory signals via activating endoplasmic reticulum stress.
Topics: Animals; Diet, High-Fat; Gastrointestinal Microbiome; Occludin; Cyprinidae; Inflammation; Antioxidants; Cypriniformes; Apoptosis; Endoplasmic Reticulum Stress; Caspases
PubMed: 37831370
DOI: 10.1007/s10695-023-01240-2 -
New Zealand Veterinary Journal Mar 2024Two clusters of mortality among endangered tūturuatu/tchūriwat'/shore plover () have occurred at captive breeding facilities around New Zealand in recent years. In the...
CASE HISTORY
Two clusters of mortality among endangered tūturuatu/tchūriwat'/shore plover () have occurred at captive breeding facilities around New Zealand in recent years. In the first, four chicks died at Pūkaha National Wildlife Centre (Mount Bruce, NZ) in February 2016, and in the second five adult birds at the Cape Sanctuary (Cape Kidnappers, NZ) died in 2022.
CLINICAL FINDINGS
In 2016, four chicks were noted to become weak, have increased vocalisations and closed eyes prior to death. The remaining chicks were treated for 5 days with amoxycillin/clavulanate orally twice daily. Water containers and brooders were cleaned and disinfected with chlorhexidine. No further mortality was seen.In the 2022 cluster, three adult breeding birds died acutely and five others showed inappetence, weight loss and diarrhoea approximately 10 days after heavy rains flooded the local river. The five birds were treated with amoxycillin/clavulanate orally twice daily and oral fluids for 5 days. Two birds died and three survived. No breeding occurred in the aviaries in the following season.
PATHOLOGICAL FINDINGS
In 2016, the chicks showed pulmonary changes ranging from congestion and oedema to heterophilic inflammation consistent with septicaemia.In 2022, the adult birds showed proliferation of bacteria in the distal small intestine associated with mucosal ulceration and heterophilic infiltration. Acid-fast staining of the caecal contents in one bird showed organisms consistent with spp.
LABORATORY FINDINGS
Aerobic bacterial cultures of the lung and liver of two affected chicks carried out in 2016 showed heavy growth of The same organism was cultured from water trays and holding tanks containing water boatmen () on which the chicks were fed.In 2022, cultures from the livers of three dead birds each showed a mixed bacterial growth with differing dominant organisms (, , and an sp.). PCR and sequencing confirmed in the caecum of one bird Fresh faeces from 24 breeding birds from the captive breeding facilities were negative by PCR for spp.The captive breeding facilities obtain water for the aviaries and aquatic invertebrates to feed to the chicks from local freshwater sources. Water quality testing at the Cape Sanctuary revealed concentrations of faecal indicator bacteria in excess of safe drinking water guidelines, with peaks following heavy rainfall.
CLINICAL RELEVANCE
Fluctuations in water quality associated with mammalian faecal bacteria can adversely affect bird health and impact on captive rearing of endangered wildlife.
Topics: Animals; Cryptosporidiosis; Water Quality; New Zealand; Cryptosporidium; Chickens; Amoxicillin; Clavulanic Acid; Mammals
PubMed: 37752889
DOI: 10.1080/00480169.2023.2263425 -
Environmental Pollution (Barking, Essex... Nov 2023Chronic kidney disease of unknown etiology (CKDu) is an endemic disease in the dry zone of farming communities, Sri Lanka. The drinking water in a CKDu prevalent area...
Chronic kidney disease of unknown etiology (CKDu) is an endemic disease in the dry zone of farming communities, Sri Lanka. The drinking water in a CKDu prevalent area contains a high concentration of F, hardness and other environmental pollutants, including heavy metals and microcystin, which are considered possible etiology of CKDu in these areas. Here, multi-omics data with host transcriptome, metabolome and gut microbiomes were obtained using simulated local drinking water of Sri Lanka after their exposure to adult zebrafish. Based on an integrated multi-omics analysis in the context of host physiology in the kidney injury samples with different pathologic grades, two common pathways necroptosis and purine metabolism were identified as potentially important pathways that affect kidney injury. The key metabolite acetyl adenylate in the purine metabolism pathway was significantly positively correlated with Comamonas (rho = 0.72) and significantly negatively correlated with Plesiomonas (rho = -0.58). This crucial metabolite and two key gut bacteria genera may not only be potential markers but also potential therapeutic targets in the uric acid metabolic pathway, which is an important factor in the pathogenesis of acute kidney injury (AKI) in general, as well as of chronic kidney disease (CKD). Based on this, we revealed the urea metabolism pathway of kidney injury in zebrafish and provided a new avenue for the treatment of CKDu in Sri Lanka.
Topics: Animals; Drinking Water; Zebrafish; Chronic Kidney Diseases of Uncertain Etiology; Multiomics; Renal Insufficiency, Chronic; Sri Lanka; Purines
PubMed: 37683759
DOI: 10.1016/j.envpol.2023.122524 -
European Journal of Medical Research Sep 2023Gallstone disease is a prevalent biliary disease worldwide, and bacteria play vital roles in the disease development and progression, as well as the prognosis after...
Gallstone disease is a prevalent biliary disease worldwide, and bacteria play vital roles in the disease development and progression, as well as the prognosis after endoscopic surgery. However, there have been limited studies to explore the key taxa involved. In this study, bile samples from healthy controls (HCs, liver donors without hepatobiliary disease) and three diseased groups, namely patients with gallbladder stones (GBS), patients with common bile duct stones (CBDS), and patients with stricture in the common bile duct (SCBD), were collected and analyzed. Bacterial community characterization based on 16S rRNA amplicon sequencing showed that bacterial diversities did not change significantly alongside gallstone disease development and progression. The predominant phyla in each group were Proteobacteria, Firmicutes, Bacteroidota, and Fusobacteriota, representing over 80% in abundance of the biliary bacteria community. Specifically, the abundance of Proteobacteria decreased greatly while that of Firmicutes and Bacteroidota increased greatly in the diseased groups when compared to that in HCs. Moreover, linear discriminant analysis identified several genera highly represented in the diseased groups. Among them, Klebsiella, Prevotella, Pseudomonas and Veillonella are persistent in both the HCs group and the diseased groups, indicating an enrichment of local bile bacteria in the diseased bile; while Lachnoanerobaculum, Atopobium, Oribacterium, and Stomatobaculum, those aligned to oral cavity taxa, are persistent in the diseased groups but are transient in the HCs group, and their abundances sequentially increased with the disease development and progression (HCs→GBS→CBDS→SCBD), implying a translocation and colonization of the oral cavity bacteria in the diseased bile. Moreover, co-occurrence network analysis revealed that bacterial infection (e.g., Photobacterium and Plesiomonas) from the intestine was developed during endoscopic surgery with reduced bile bacteria diversity. The results of this study revealed that the bile bacterial community is relatively stable and dominated by a few persistent taxa. Moreover, we hypothesized that translocation and colonization of specific bacteria from the oral cavity happens alongside gallstone disease development and progression, and bacterial infection from the intestinal tract results in poor outcomes after endoscopic surgery.
Topics: Humans; Gallstones; Bile; RNA, Ribosomal, 16S; Bacteria; Constriction, Pathologic; Disease Progression
PubMed: 37660138
DOI: 10.1186/s40001-023-01308-y -
PeerJ 2023The Andean condor () is the largest scavenger in South America. This predatory bird plays a crucial role in their ecological niche by removing carcasses. We report the...
BACKGROUND
The Andean condor () is the largest scavenger in South America. This predatory bird plays a crucial role in their ecological niche by removing carcasses. We report the first metagenomic analysis of the Andean condor gut microbiome.
METHODS
This work analyzed shotgun metagenomics data from a mixture of fifteen captive Chilean Andean condors. To filter eukaryote contamination, we employed BWA-MEM v0.7. Taxonomy assignment was performed using Kraken2 and MetaPhlAn v2.0 and all filtered reads were assembled using IDBA-UD v1.1.3. The two most abundant species were used to perform a genome reference-guided assembly using MetaCompass. Finally, we performed a gene prediction using Prodigal and each gene predicted was functionally annotated. InterproScan v5.31-70.0 was additionally used to detect homology based on protein domains and KEGG mapper software for reconstructing metabolic pathways.
RESULTS
Our results demonstrate concordance with the other gut microbiome data from New World vultures. In the Andean condor, Firmicutes was the most abundant phylum present, with , a potentially pathogenic bacterium for other animals, as dominating species in the gut microbiome. We assembled all reads corresponding to the top two species found in the condor gut microbiome, finding between 94% to 98% of completeness for and , respectively. Our work highlights the ability of the Andean condor to act as an environmental reservoir and potential vector for critical priority pathogens which contain relevant genetic elements. Among these genetic elements, we found 71 antimicrobial resistance genes and 1,786 virulence factors that we associated with several adaptation processes.
Topics: Animals; Gastrointestinal Microbiome; Metagenomics; Falconiformes; Acclimatization; Chile; Clostridium perfringens
PubMed: 37434868
DOI: 10.7717/peerj.15235 -
The Journal of Maternal-fetal &... Dec 2023The consumption of raw seafood, generally considered to be a healthy food, has greatly increased worldwide. Pathogens of fish can cause foodborne illnesses in humans,...
The consumption of raw seafood, generally considered to be a healthy food, has greatly increased worldwide. Pathogens of fish can cause foodborne illnesses in humans, especially following the consumption of raw seafood from contaminated water.Foodborne illness in pregnant women is seldom the cause of neonatal infection, but, as in the reported cases, it has been associated with a high degree of morbidity and mortality.We present the case of a newborn with septicemia and meningitis caused by Plesiomonas shigelloides acquired the transplacental route. There was a maternal history of ingestion of raw seafood 1 week prior to delivery. A few similar cases are described in the existing literature, which reports 7 neonatal deaths.Therefore, the primary objective of this paper is to highlight the fact that the popularity of raw seafood such as sushi, sashimi, and oysters, requires an improvement in dietary advice regarding unsafe choices in pregnancy in order to avoid preventable foodborne diseases, sometimes fatal for the newborn.
Topics: Infant, Newborn; Animals; Humans; Female; Pregnancy; Plesiomonas; Dietary Exposure; Sepsis; Meningitis; Seafood
PubMed: 37271970
DOI: 10.1080/14767058.2023.2220061