Publications by authors named "Huahai Chen"

Introduction: Segmented filamentous bacteria (SFB) colonization dynamics are crucial for host immune regulation. Given this, the present study specifically examined the functions of SFB flagellin in bacterial adhesion, cellular internalization, and immune modulation.

Methods: and were engineered to express murine and rat SFB flagellin genes.

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Pneumonia caused by Mesomycoplasma hyopneumoniae (Mhp) is a respiratory disease with high morbidity and low mortality that typically presents in growing pigs. Although often subclinical, the disease can significantly affect the pig farming industry economically due to decreased growth rates and inefficient feed conversion. Effective control of Mhp depends on the detection of dominant strains prevalent in infected animals, which vary in virulence.

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Unlabelled: With its estrogenic activity, ()-equol plays an important role in maintaining host health and preventing estrogen-related diseases. Exclusive production occurs through the transformation of soy isoflavones by intestinal bacteria, but the reasons for variations in ()-equol production among different individuals and species remain unclear. Here, fecal samples from humans, pigs, chickens, mice, and rats were used as research objects.

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This work was performed on commercially purchased CVCC519 originally isolated from chicken intestinal content. The Sanguinarine-resistant strain XM3104 was isolated from Sanguinarine-induced CVCC519. To identify possible mechanisms underlying resistance, the complete genomes of CVCC519 and XM3104 were sequenced using PromethION and next-generation sequencing.

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Lactobacillus amylovorus has been reported to reduce weight and fat content in humans. To identify and understand the mechanism underlying this process, the complete genome of CICC 6090, which was isolated from pig intestines, was sequenced using PromethION and next-generation sequencing.

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Genome sequences of 4 644 representative strains from human gut microbiota were analyzed to mine gene clusters for biosynthesis of novel secondary metabolites, as well as genes encoding antibiotic resistance and virulence factors. AntiSMASH analysis showed that more than 60% of the representative strains encoded at least one secondary metabolite gene cluster, and 8 potential novel secondary metabolite gene clusters were identified from 8 unculturable bacteria. The secondary metabolite gene clusters in human intestine are mainly composed of nonribosomal peptide synthetase (NRPS), bacteriocin, arylpolyene, terpene, betalactone and NRPS like gene clusters distributed in Clostridia, Bacilli, Gammaproteobacteria, Bacteroidia, Actinobacteria and Negativicutes.

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Esophageal microbiota plays important roles in esophageal squamous cell carcinoma (ESCC). The aims of this study were to clarify the changes in the bacterial community during ESCC development and identify latent pathogenic bacteria which may contribute to esophageal carcinogenesis and progression. Fresh tumor and nontumor esophageal mucosal samples were collected from 31 men with ESCC.

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Article Synopsis
  • ()-equol (EQ) is an isoflavone with significant estrogen-like effects produced only by certain gut bacteria, essential for health, but its production has been limited due to a lack of resources.
  • Researchers identified a novel functional gene, K-07020, from a specific gut bacterium that can convert daidzein into dihydrodaidzein and can also reverse this process without cofactors.
  • The study found that K-07020 potentially enhances EQ production and is widely distributed in human and animal guts, indicating promising avenues for understanding and manipulating EQ-producing bacteria.
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Antibiotic resistance is a serious medical issue driven by antibiotic misuse. Bifidobacteria may serve as a reservoir for antibiotic resistance genes (ARGs) that have the potential risk of transfer to pathogens. The erythromycin resistance gene (X) is an ARG with high abundance in bifidobacteria, especially in Bifidobacterium longum species.

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The research on the relationship between gut microbiota and human health continues to be a hot topic in the field of life science. Culture independent 16S rRNA gene high-throughput sequencing is the current main research method. However, with the reduction of sequencing cost and the maturity of data analysis methods, shotgun metagenome sequencing is gradually becoming an important method for the study of gut microbiome due to its advantages of obtaining more information.

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A stable intestinal microflora is an essential prerequisite for human health. This study investigated the interaction between exopolysaccharides (named EPS-m2) and the human gut microbiota (HGM) . The EPS-m2 was produced by .

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Bifidobacteria are typical commensals inhabiting the human intestine and are beneficial to the host because of their probiotic properties. One of the risks concerning probiotics is the potential of introducing antibiotic resistance genes (ARGs) to the host gut pathogens. This study was aimed to depict the general antibiotic resistance characteristics of the genus Bifidobacterium by combining the reported phenotype dataset and in silico genotype prediction.

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Statins, a class of drugs that can effectively remove cholesterol from serum, are used to regulate plasma total cholesterol and reduce the risk of cardiovascular diseases, but it is still unclear whether the drug are modulated by gut microbiota or the structures of gut microbiota are shaped by statins. We investigated the interactions between statins and the human gut microbiota during the in vitro fermentation process by 16S rRNA gene sequencing, gas chromatography (GC), and high-performance liquid chromatography (HPLC) analyses. The presence of fluvastatin (FLU2) specifically promoted the growth of Escherichia/Shigella, Ruminococcaceae UCG 014, and Sutterella.

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T-helper-17 (Th17) cells are a subset of CD4+ T cells that can produce the cytokine interleukin (IL)-17 and play vital roles in protecting the host from bacterial and fungal infections, especially at the mucosal surface. These are abundant in the small intestinal lamina propria (SILP) and their differentiation are associated with the colonization of the intestinal flora. Segmented filamentous bacteria (SFB) drew the attention of researchers due to their unique ability to drive the accumulation of Th17 cells in the SI LP of mice.

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In this study, an exopolysaccharide (EPS) named EPS-RB was produced when the gene cluster ycjD-fabI-yciW-rnb were overexpressed in E. coli. Monosaccharide composition analysis revealed that EPS-RB is a novel EPS that consisted of L-fucose, L-arabinose, D-galactose/N-acetyl glucosamine, D-glucose, D-xylose, D-ribose, and D-glucuronic acid, and their molecular ratio was approximately 80:3:53:69:1:2:64.

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Segmented filamentous bacteria (SFB) are well known for their functions in the immunoregulation of hosts including the promotion of Th17 cell differentiation, B cell maturation, and immune system development. However, most analyses of SFB have focused on animal models, and thus, investigation of SFB prevalence in humans and their roles in human immunoregulation and health is needed. Although little is known overall of SFB prevalence in humans, they are characteristically abundant in animals during weaning.

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Human intestinal microorganisms have recently become an important target of research in promoting human health and preventing diseases. Consequently, investigations of interactions between endobiotics (e.g.

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To further investigate the bacterial community and identify the bacterial biomarkers between venom secretion and non-venom secretion snakes, 50 intestinal samples (25 large intestine, 25 small intestine) were obtained from 29 snakes (13 gut samples from Deinagkistrodon, 26 from Naja and 11 from Ptyas mucosa). 16S rDNA high-throughput sequencing results showed that 29 bacterial phyla, 545 bacterial genera, and 1,725 OTUs (operational taxonomic units) were identified in these samples. OTU numbers and the Ace, Chao, Shannon, and Simpson indexes were very similar among the three breeds of snakes included in this study.

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Exopolysaccharides (EPSs) are carbohydrate polymers that are synthesized and present on the surface of bifidobacteria. Due to their potential applications in diverse sectors, such as food, biotechnology, cosmetics, and medicine, EPSs synthesized by bifidobacteria have recently attracted more attention. EPS production not only has benefits in food and health but also has effects on probiotics in the microbial ecosystem.

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The surface exopolysaccharide of Bifidobacterium spp. was found to be involved in many processes, including bacterial colonization and host immune modulation. Here, we report the draft genome sequence of an exopolysaccharide-producing strain of Bifidobacterium longum, BB-79.

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Antimicrobial resistance is on the rise while the number of antibiotics being brought to market continues to drop. Drug-resistant genes and drug-resistant bacteria infection have seriously threatened human health. Therefore, antimicrobial resistance presents an ongoing challenge that requires multifaceted approaches including: biomedical innovation; improved surveillance of antibiotic consumption and antimicrobial resistance generated rates; prevention of health-care-associated infections and transmission of multidrug-resistant bacteria and environmental dissemination; rapid microbiological diagnosis; and curtailed clinical and veterinary misuse.

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Segmented filamentous bacteria (SFB) are commensal organisms that grow by anchoring a specialized holdfast structure to the intestinal walls of a variety of animals. Interaction of SFB with Peyer's patches in mice promotes the post-natal maturation of the immune system. We previously reported that the colonization of SFB in humans mainly occurs by 36 months of age, and is difficult to be detected afterward.

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()-equol is one of the major metabolites of daidzein that is produced by human and animal gut bacteria. Most of the physiological functions of soybean isoflavones, such as anti-oxidative activity, anti-cancer activity, and cardiovascular protection have been ascribed to ()-equol. However, only 30-50% people contain this kind of equol-producing bacteria, and therefore are able to convert daidzein to ()-equol.

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