-
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 -
Heliyon Jun 2024, an aquatic bacterium belonging to the Enterobacteriaceae family, is a frequent cause of gastroenteritis with diarrhea and gastrointestinal severe disease. Despite...
, an aquatic bacterium belonging to the Enterobacteriaceae family, is a frequent cause of gastroenteritis with diarrhea and gastrointestinal severe disease. Despite decades of research, discovering a licensed and globally accessible vaccine is still years away. Developing a putative vaccine that can combat the infection by boosting population immunity against is direly needed. In the framework of the current study, the entire proteome of was explored using subtractive genomics integrated with the immunoinformatics approach for designing an effective vaccine construct against . The overall stability of the vaccine construct was evaluated using molecular docking, which demonstrated that MEV showed higher binding affinities with toll-like receptors (TLR4: 51.5 ± 10.3, TLR2: 60.5 ± 9.2) and MHC receptors(MHCI: 79.7 ± 11.2 kcal/mol, MHCII: 70.4 ± 23.7). Further, the therapeutic efficacy of the vaccine construct for generating an efficient immune response was evaluated by computational immunological simulation. Finally, computer-based cloning and improvement in codon composition without altering amino acid sequence led to the development of a proposed vaccine. In a nutshell, the findings of this study add to the existing knowledge about the pathogenesis of this infection. The schemed MEV can be a possible prophylactic agent for individuals infected with . Nevertheless, further authentication is required to guarantee its safeness and immunogenic potential.
PubMed: 38845922
DOI: 10.1016/j.heliyon.2024.e31304 -
Virulence Dec 2023spp. are the causative agent of shigellosis (or bacillary dysentery), a diarrhoeal disease characterized for the bacterial invasion of gut epithelial cells. Among the 4... (Review)
Review
spp. are the causative agent of shigellosis (or bacillary dysentery), a diarrhoeal disease characterized for the bacterial invasion of gut epithelial cells. Among the 4 species included in the genus, is principally responsible for the disease in the developing world while is the main causative agent in high-income countries. Remarkably, as more countries improve their socioeconomic conditions, we observe an increase in the relative prevalence of . To date, the reasons behind this change in aetiology depending on economic growth are not understood. has been widely used as a model to study the pathogenesis of the genus, but as more research data are collected, important discrepancies with have come to light. In comparison to can be differentiated in numerous aspects; it presents a characteristic O-antigen identical to that of one serogroup of the environmental bacterium , a group 4 capsule, antibacterial mechanisms to outcompete and displace gut commensal bacteria, and a poorer adaptation to an intracellular lifestyle. In addition, the World Health Organization (WHO) have recognized the significant threat posed by antibiotic-resistant strains of , demanding new approaches. This review gathers knowledge on what is known about within the context of other spp. and aims to open the door for future research on understanding the increasing spread of this pathogen.
Topics: Humans; Shigella sonnei; Virulence; Prevalence; Anti-Bacterial Agents; Cell Differentiation; Dysentery, Bacillary
PubMed: 37994877
DOI: 10.1080/21505594.2023.2280838 -
PloS One 2024This study aimed to investigate the cause of a foodborne disease outbreak in Huzhou on August 14, 2023. Multiple enteropathogens were detected using FilmArray, and the...
This study aimed to investigate the cause of a foodborne disease outbreak in Huzhou on August 14, 2023. Multiple enteropathogens were detected using FilmArray, and the pathogen was subsequently isolated and cultured from anal swabs of the cases and stream water. The isolated strains were identified using VITEK MS, and antimicrobial susceptibility test, pulsed field gel electrophoresis (PFGE) molecular typing, and whole genome sequencing (WGS) were performed on the isolates of Plesiomonas shigelloides. Gene annotation and sequence alignment were used to analyze the virulence genes and drug resistance genes of the strains. A phylogenetic tree was constructed based on single nucleotide polymorphism (SNP), and homology analysis was conducted to trace the origin of P. shigelloides. A total of 7 strains of P.shigelloides were isolated, with 3 from stream water and 4 from anal swabs. All 7 strains exhibited the same PFGE pattern and showed resistance to amikacin, trimethoprim-sulfamethoxazole, chloramphenicol, tetracycline, cefazolin, streptomycin, and florfenicol. The isolated strains carried the same resistance genes and virulence factors. In the sequences of the isolated strains from this outbreak, 11 mutation sites were detected. The phylogenetic tree based on SNP sites showed that these strains were homologous. This foodborne disease outbreak caused by P.shigelloides was the first reported in Huzhou. WGS can be used as a complementary method to PFGE for epidemiological investigations of disease outbreaks.
Topics: Humans; Plesiomonas; Rivers; Phylogeny; Diarrhea; Foodborne Diseases; Water
PubMed: 38574097
DOI: 10.1371/journal.pone.0301623 -
Aquaculture Nutrition 2023Citric acid is an organic acid extensively used in feed industry, and AZOMITE is a hydrated aluminosilicate compound rich in rare earth elements and trace mineral...
Citric acid is an organic acid extensively used in feed industry, and AZOMITE is a hydrated aluminosilicate compound rich in rare earth elements and trace mineral elements. This study investigated the supplemental effects of AZOMITE and citric acid individual or in combination on the growth performance, intestinal microbiota, morphology, digestive enzyme activity, serum indexes, and disease resistance of juvenile largemouth bass. Six diets were designed, including the control diet (CON) and the five additive-supplemented diets with the addition of 4 or 8 g/kg citric acid (CA4, CA8), 3 g/kg AZOMITE (A3), and their combined addition as 4 g/kg citric acid + 1.5 g/kg AZOMITE) (C4A1.5) and 8 g/kg citric acid + 3 g/kg AZOMITE (C8A3). Juvenile largemouth bass with initial body weight of 22.01 ± 0.09 g were fed the six diets for 56 days. The results revealed that the combined addition of 4 g/kg citric acid and 1.5 g/kg AZOMITE (C4A1.5) increased weight gain by 7.99% ( < 0.05), and decreased feed conversion ratio by 0.07 ( < 0.05). The protein retention in the C4A1.5 group and the lipid retention in all additive-supplemented groups were significantly higher than those in the control group ( < 0.05). In serum, all additive-supplemented groups showed significantly higher glutathione peroxidase activity than the control group ( < 0.05). The activities of superoxide dismutase and catalase in the CA8, A3, C4A1.5, and C8A3 groups were significantly higher ( < 0.05), while the concentration of malondialdehyde was significantly lower than those in the control group ( < 0.05). Moreover, the total antioxidant capacity in the A3 and C4A1.5 groups, and lysozyme activity in the A3, C4A1.5, and C8A3 groups were significantly increased when compared to the control group ( < 0.05). In digestive enzyme, the protease activity in the A3, C4A1.5 groups, and amylase activity in the CA4, CA8, and C4A1.5 groups were significantly higher than those in the control group ( < 0.05). In intestinal microbiota, abundance was elevated in all additive groups, while the and abundance were decreased. In the intestinal histology, the CA8, A3, and C4A1.5 groups showed significantly higher villus height than the control group ( < 0.05). After the infection with , the cumulative mortality of all additive-supplemented groups was significantly lower ( < 0.05), and the C4A1.5 group demonstrated the lowest mortality. In conclusion, the combined supplementation of 4 g/kg citric acid + 1.5 g/kg AZOMITE increased the growth, antioxidant, immune capacity, improved the intestinal morphology and microbial flora of juvenile largemouth bass, and promoted the resistance against infection.
PubMed: 37881475
DOI: 10.1155/2023/5022456 -
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 -
Antioxidants (Basel, Switzerland) Dec 2023A 10-week growth experiment was conducted to assess the physiological response of spotted seabass () raised at moderate (27 °C) and high temperatures (33 °C) to...
Physiological Response of Spotted Seabass () to Different Dietary Available Phosphorus Levels and Water Temperature: Changes in Growth, Lipid Metabolism, Antioxidant Status and Intestinal Microbiota.
A 10-week growth experiment was conducted to assess the physiological response of spotted seabass () raised at moderate (27 °C) and high temperatures (33 °C) to different dietary available phosphorus (P) levels. Five diets with available P levels of 0.35, 0.55, 0.71, 0.82 and 0.92% were formulated, respectively. A water temperature of 33 °C significantly decreased growth performance and feed utilization, and increased oxidative stress and lipid deposition of spotted seabass compared with 27 °C. A second-order polynomial regression analysis based on weight gain (WG) showed that the available P requirement of spotted seabass raised at 27 °C and 33 °C was 0.72% and 0.78%, respectively. The addition of 0.71-0.82% P to the diet improved the growth performance, feed utilization, and antioxidant capacity of spotted seabass and alleviated the excessive lipid deposition compared with the low-P diet (0.35% P). Moreover, the addition of 0.71-0.92% P to diets increased the diversity of intestinal microbiota and the relative abundance of and decreased the relative abundance of compared with the low-P diet. Thus, dietary supplementation with 0.71-0.82% P improved the growth performance, antioxidant capacity and microbial composition of spotted seabass, and alleviated the disturbance of lipid metabolism caused by high temperature or low-P diet.
PubMed: 38136247
DOI: 10.3390/antiox12122128 -
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 -
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 -
Ecotoxicology and Environmental Safety Mar 2024The mechanism by which Y. ruckeri infection induces enteritis in Chinese sturgeon remains unclear, and the efficacy of drug prevention and control measures is not only...
The mechanism by which Y. ruckeri infection induces enteritis in Chinese sturgeon remains unclear, and the efficacy of drug prevention and control measures is not only poor but also plagued with numerous issues. We conducted transcriptomic and 16 S rRNA sequencing analyses to examine the differences in the intestinal tract of hybrid sturgeon before and after Y. ruckeri infection and florfenicol intervention. Our findings revealed that Y. ruckeri induced the expression of multiple inflammatory factors, including il1β, il6, and various chemokines, as well as casp3, casp8, and multiple tumor necrosis factor family members, resulting in pathological injury to the body. Additionally, at the phylum level, the relative abundance of Firmicutes and Bacteroidota increased, while the abundance of Plesiomonas and Cetobacterium decreased at the genus level, altering the composition of the intestinal flora. Following florfenicol intervention, the expression of multiple apoptosis and inflammation-related genes was down-regulated, promoting tissue repair. However, the flora became further dysregulated, increasing the risk of infection. In conclusion, our analysis of the transcriptome and intestinal microbial composition demonstrated that Y. ruckeri induces intestinal pathological damage by triggering apoptosis and altering the composition of the intestinal microbiota. Florfenicol intervention can repair pathological damage, but it also exacerbates flora imbalance, leading to a higher risk of infection. These findings help elucidate the molecular mechanism of Y. ruckeri-induced enteritis in sturgeon and evaluate the therapeutic effect of drugs on intestinal inflammation in sturgeon.
Topics: Animals; Yersinia ruckeri; Yersinia Infections; Fish Diseases; Fishes; Enteritis; Inflammation; Oncorhynchus mykiss; Thiamphenicol
PubMed: 38394759
DOI: 10.1016/j.ecoenv.2024.116138