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Rational protein engineering of thermostable heparinase I from Bacteroides thetaiotaomicron for highly efficient heparin degradation
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作者 Chuan Zhang Ruohan Zhao +6 位作者 Leilei Yu Qixiao Zhai Jianxin Zhao Hao Zhang Xuegang Luo Fengwei Tian Wei Chen 《Food Science and Human Wellness》 2025年第6期2161-2171,共11页
Heparin,a glycosaminoglycan,is a stable source of carbon that supports the growth of microorganisms in the human intestine.It is also a commonly used anticoagulant drug in clinical practice,with significant therapeuti... Heparin,a glycosaminoglycan,is a stable source of carbon that supports the growth of microorganisms in the human intestine.It is also a commonly used anticoagulant drug in clinical practice,with significant therapeutic effects.Low molecular weight heparin(LMWH)is a highly active low molecular weight fragment obtained via enzymatic reaction or the chemical degradation of heparin.LMWH has been applied globally in the prevention and treatment of venous thromboembolism in thrombosis patients.Simultaneously,as a potential prebiotic,because of its low molecular weight,LMWH can be well degraded by the gut microbiota to maintain intestinal balance.Enzymatic heparin degradation has recently emerged as a viable disposal method for LMWH preparation;however,only very few benchmark enzymes have been thoroughly described and subjected to protein engineering to improve their properties over the past few years.The commercialization of enzymes will require the development of robustly engineered enzymes that meet the demands of industrial processes.Herein,we report a rational protein engineering strategy that includes molecular dynamic simulations of flexible amino acid mutations and disulfide bond screening.Several Bacteroides thetaiotaomicron heparanase I(Bt-HepI)mutants were obtained and screened for high thermal stability.We obtained the Bt-HepI^(D204C/K208C/H189W/Q198R)variant,which features a stabilized protein surface structure,with a 1.3-fold increase in catalytic constant/michaelis-menten constant(k_(cat)/K_(m)),a 2.44-fold increase in thermal stability at 50℃,and a 1.8-fold decrease in the average molecular weight of LMWH produced at 40℃compared with that seen with Bt-HepI^(WT).Our study establishes a strategy to engineer thermostable HepI to underpin its industrial applications. 展开更多
关键词 HEPARIN bacteroides thetaiotaomicron Heparinase I Rational protein engineering Thermostability
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Bacteroides vulgatus FTJS7K1胞外囊泡调控肠道屏障的体外研究
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作者 孙荣昕 蒋璐 +3 位作者 薛丽莹 曹佳媛 刘伊索 易华西 《中国乳品工业》 北大核心 2025年第4期13-19,共7页
普通拟杆菌是重要的肠道共生菌,胞外囊泡是普通拟杆菌分泌的胞外代谢产物,其生物活性和作用机制尚不明确。以源于健康人体肠道的普通拟杆菌FTJS7K1为研究对象,通过建立Caco-2/RAW264.7共培养细胞模型,体外探究普通拟杆菌FTJS7K1胞外囊... 普通拟杆菌是重要的肠道共生菌,胞外囊泡是普通拟杆菌分泌的胞外代谢产物,其生物活性和作用机制尚不明确。以源于健康人体肠道的普通拟杆菌FTJS7K1为研究对象,通过建立Caco-2/RAW264.7共培养细胞模型,体外探究普通拟杆菌FTJS7K1胞外囊泡对肠道屏障的保护作用。结果表明,普通拟杆菌FTJS7K1胞外囊泡能缓解LPS引起的Caco-2单层细胞跨膜电阻值下降,减少FITC-Dextran透过肠道屏障;促进Claudin-1、ZO-1、Occludin等紧密连接蛋白mRNA表达;普通拟杆菌FTJS7K1胞外囊泡干预后Caco-2/RAW264.7共培养体系后,TNF-α、INF-γ、IL-1β等促炎因子和NO的水平降低,抗炎因子IL-10水平升高。文章不仅为探索肠道菌群的健康功效机制提供新思路,而且为开发基于益生菌胞外囊泡的功能性膳食补充剂提供理论依据。 展开更多
关键词 肠道菌群 普通拟杆菌 胞外囊泡 肠道屏障 调控
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基于PCR-DGGE和拟杆菌(Bacteroides)16S rRNA的岩溶地下水粪便污染来源示踪研究:以重庆南山老龙洞地下河系统为例 被引量:3
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作者 张弘 蒋勇军 +3 位作者 张远瞩 段逸凡 吕现福 贺秋芳 《环境科学》 EI CAS CSCD 北大核心 2016年第5期1805-1813,共9页
岩溶地下水的微生物污染日益严重,其来源的研究得到国际学术界的广泛关注.本研究以重庆南山老龙洞岩溶地下河系统为对象,采用滤膜法监测地下水中的总细菌、大肠杆菌、粪大肠菌及粪链球菌等微生物指标,以拟杆菌(Bacteriodes)为指示细菌,... 岩溶地下水的微生物污染日益严重,其来源的研究得到国际学术界的广泛关注.本研究以重庆南山老龙洞岩溶地下河系统为对象,采用滤膜法监测地下水中的总细菌、大肠杆菌、粪大肠菌及粪链球菌等微生物指标,以拟杆菌(Bacteriodes)为指示细菌,采用PCR-DGGE示踪地下水中大肠杆菌/粪大肠杆菌的来源.结果表明,老龙洞地下河流域各类细菌含量严重超标,总细菌数为10~2.9×10~7CFU·m L^(-1),大肠菌群总数达4.3~4.0×10~5CFU·m L^(-1),其中粪大肠菌群(FC)和粪链球菌(FS)分别最高达到1.1×10~6CFU·(100 m L)^(-1)、1.1×10~5CFU·(100 m L)^(-1);FC/FS多数为2以上,暗示流域地下水受人类粪便影响为主.地下水样和粪便样品的拟杆菌群落的PCR-DGGE比对分析表明地下水与人粪之间相似性为7.1%~69.1%,其中地下河出口处达到69.1%.地下水与猪粪之间相似性为1.1%~53.4%,地下河出口处仅为1.5%.因此,人类粪便为地下河污染的主要来源,猪粪污染为动物粪便污染的一部分,还存在其他动物粪便污染来源.此外,PCR-DGGE产物切胶测序发现大部分Bacteroides为人类肠道或粪便来源的细菌. 展开更多
关键词 岩溶地下水 粪便污染 大肠菌群 拟杆菌 PCR-DGGE
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Bacteroides-derived isovaleric acid enhances mucosal immunity by facilitating intestinal IgA response in broilers 被引量:8
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作者 Xinkai Wang Yifan Hu +3 位作者 Xiaoyan Zhu Liyuan Cai Muhammad Zahid Farooq Xianghua Yan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1252-1273,共22页
Background:The interaction between nutrition and immunity plays a vital role in nutrient digestion,absorption,and metabolism during poultry production.Recent studies showed that the gut microbiota contributes to the d... Background:The interaction between nutrition and immunity plays a vital role in nutrient digestion,absorption,and metabolism during poultry production.Recent studies showed that the gut microbiota contributes to the development of intestinal mucosal immunity.However,the mechanisms by which gut microbes regulate this process remain unclear.Methods:We compared the intestinal mucosal immunity and gut microbiota of Arbor Acre broilers AA(lower mucosal immunity)and Chinese native Wuliang Mountain Black-bone chickens(WLMB)(higher mucosal immunity)using 16S rDNA sequencing,transcriptomic analysis,and immunoglobulin A(IgA)antibody repertoire sequencing.We then combined 16S rDNA sequencing with transcriptomics to identify the key microbes and found that they were positively correlated with IgA production.Next,we transplanted candidate microbes into 1-day-old broiler to explore their role in intestinal mucosal immunity.Finally,we verified the function of candidate microbial metabolites in regulating the immune function of macrophages and the intestinal-epithelial cells(IECs)using in vitro experiments.Results:WLMB performs stronger mucosal immunity than AA,including higher IgA levels,more diverse IgA antibody repertoire,and higher bacterial affinity.Bacteroides was identified as the key microbes related to the intestinal IgA response.Bacteroides transplantation could increase IgA concentration in the duodenal contents by enhancing the expression of IgA,polymeric immunoglobin receptor(PIgR),B cell-activating factor of the TNF family(BAFF),and activation-induced cytidine deaminase(AID)in the duodenum.Additionally,Bacteroides-derived isovaleric acid promoted M2 macrophage polarization of macrophage via mTOR/PPAR-γ/STAT3 signaling pathways and regulated the immunologic function of IECs to produce cytokines,including interleukin(IL)-10,IL-4,BAFF,and transforming growth factor-beta(TGF-β),thus promoting IgA production in B cells by facilitating AID expression.Conclusion:Our study revealed that Bacteroides modulate the intestinal IgA response and maintain gut health in broilers.Bacteroides may be a promising alternative as an immunomodulatory microbial agent for developing nextgeneration probiotics for broiler production. 展开更多
关键词 bacteroidES CHICKEN IGA Intestinal health Isovaleric acid MACROPHAGE
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Bacteroides utilization for dietary polysaccharides and their beneficial effects on gut health 被引量:12
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作者 Jiaobo Cheng Jielun Hu +1 位作者 Fang Geng Shaoping Nie 《Food Science and Human Wellness》 SCIE 2022年第5期1101-1110,共10页
Polysaccharide was a class of macromolecular substance with various bioactive functions.Gut symbiotic microorganisms could utilize the polysaccharides from various sources,thus have important impact on human health.Ba... Polysaccharide was a class of macromolecular substance with various bioactive functions.Gut symbiotic microorganisms could utilize the polysaccharides from various sources,thus have important impact on human health.Bacteroides represented one of the dominant colonizers in the human gut.The utilization of polysaccharide by Bacteroides was important for supporting the function and stability of gut microbiota.After the degradation of polysaccharides by Bacteroides,gut microbes could ferment the monosaccharides and oligosaccharides degraded from polysaccharides into some metabolites,such as short-chain fatty acids(SCFAs),amino acids,etc.Among the metabolites,the SCFAs could have beneficial effects on gut health.This review summarized the niches of Bacteroides among gut microbiota,and also described the gene clusters and membrane proteins involved in the utilization processes of polysaccharide by gut Bacteroides.SCFAs could act as energy substrates for intestinal epithelial cells,inhibit histone deacetylases and activate G protein-coupled receptors.In addition,the future perspectives in investigating new degradation pathways for polysaccharide,and using polysaccharides or their metabolites as therapeutic approaches for diseases mediated by the gut dysbiosis were also provided. 展开更多
关键词 bacteroidES POLYSACCHARIDES DEGRADATION Short-chain fatty acids Gut health
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Suppression of colorectal tumorigenesis by recombinant Bacteroides fragilis enterotoxin-2 in vivo 被引量:4
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作者 You Lv Tao Ye +6 位作者 Hui-Peng Wang Jia-Ying Zhao Wen-Jie Chen Xin Wang Chen-Xia Shen Yi-Bin Wu Yuan-Kun Cai 《World Journal of Gastroenterology》 SCIE CAS 2017年第4期603-613,共11页
AIM To evaluate the impact of recombinant Bacteroides fragilis enterotoxin-2 (BFT-2, or Fragilysin) on colorectal tumorigenesis in mice induced by azoxymethane/dextran sulfate sodium (AOM/DSS). METHODS Recombinant pro... AIM To evaluate the impact of recombinant Bacteroides fragilis enterotoxin-2 (BFT-2, or Fragilysin) on colorectal tumorigenesis in mice induced by azoxymethane/dextran sulfate sodium (AOM/DSS). METHODS Recombinant proBFT-2 was expressed in Escherichia coli strain Rosetta (DE3) and BFT-2 was obtained and tested for its biological activity via colorectal adenocarcinoma cell strains SW-480. Seventy C57BL/6J mice were randomly divided into a blank (BC; n = 10), model (AD; n = 20), model + low-dose toxin (ADLT; n = 20, 10 mu g), and a model + high-dose toxin (ADHT; n = 20, 20 mu g) group. Mice weight, tumor formation and pathology were analyzed. Immunohistochemistry determined Ki-67 and Caspase-3 expression in normal and tumor tissues of colorectal mucosa. RESULTS Recombinant BFT-2 was successfully obtained, along with its biological activity. The most obvious weight loss occurred in the AD group compared with the ADLT group (21.82 +/- 0.68 vs 23.23 +/- 0.91, P < 0.05) and the ADHT group (21.82 +/- 0.68 vs 23.57 +/- 1.06, P < 0.05). More tumors were found in the AD group than in the ADLT and ADHT groups (19.75 +/- 3.30 vs 6.50 +/- 1.73, P < 0.05; 19.75 +/- 3.30 vs 6.00 +/- 2.16, P < 0.05). Pathology showed that 12 mice had adenocarcinoma and 6 cases had adenoma in the AD group. Five mice had adenocarcinoma and 15 had adenoma in the ADLT group. Four mice had adenocarcinoma and 16 had adenoma in the ADHT group. The incidence of colorectal adenocarcinoma in both the ADHT group and the ADHT group was reduced compared to that in the AD group (P < 0.05, P < 0.05). The positive rate of Ki-67 in the ADLT group and the ADHT group was 50% and 40%, respectively, both of which were lower than that found in the AD group (94.44%, P < 0.05, P < 0.05). Caspase-3 expression in the ADLT group and the ADHT group was 45% and 55%, both of which were higher than that found in the BC group (16.67%, P < 0.05, P < 0.05). CONCLUSION Oral administration with lower-dose biologically active recombinant BFT-2 inhibited colorectal tumorigenesis in mice. 展开更多
关键词 Colorectal neoplasms bacteroides fragilis toxin Fragilysin Recombinant proteins MICE
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Bacteroides fragilis enterotoxin upregulates heme oxygenase-1 in dendritic cells via reactive oxygen species-,mitogen-activated protein kinase-,and Nrf2-dependent pathway 被引量:2
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作者 Su Hyuk Ko Jong Ik Jeon +1 位作者 Hyun Ae Woo Jung Mogg Kim 《World Journal of Gastroenterology》 SCIE CAS 2020年第3期291-306,共16页
BACKGROUND Enterotoxigenic Bacteroides fragilis(ETBF)causes colitis and diarrhea,and is considered a candidate pathogen in inflammatory bowel diseases as well as colorectal cancers.These diseases are dependent on ETBF... BACKGROUND Enterotoxigenic Bacteroides fragilis(ETBF)causes colitis and diarrhea,and is considered a candidate pathogen in inflammatory bowel diseases as well as colorectal cancers.These diseases are dependent on ETBF-secreted toxin(BFT).Dendritic cells(DCs)play an important role in directing the nature of adaptive immune responses to bacterial infection and heme oxygenase-1(HO-1)is involved in the regulation of DC function.AIM To investigate the role of BFT in HO-1 expression in DCs.METHODS Murine DCs were generated from specific pathogen-free C57BL/6 and Nrf2−/−knockout mice.DCs were exposed to BFT,after which HO-1 expression and the related signaling factor activation were measured by quantitative RT-PCR,EMSA,fluorescent microscopy,immunoblot,and ELISA.RESULTS HO-1 expression was upregulated in DCs stimulated with BFT.Although BFT activated transcription factors such as NF-κB,AP-1,and Nrf2,activation of NF-κB and AP-1 was not involved in the induction of HO-1 expression in BFT-exposed DCs.Instead,upregulation of HO-1 expression was dependent on Nrf2 activation in DCs.Moreover,HO-1 expression via Nrf2 in DCs was regulated by mitogenactivated protein kinases such as ERK and p38.Furthermore,BFT enhanced the production of reactive oxygen species(ROS)and inhibition of ROS production resulted in a significant decrease of phospho-ERK,phospho-p38,Nrf2,and HO-1 CONCLUSION These results suggest that signaling pathways involving ROS-mediated ERK and p38 mitogen-activated protein kinases-Nrf2 activation in DCs are required for HO-1 induction during exposure to ETBF-produced BFT. 展开更多
关键词 bacteroides fragilis enterotoxin Dendritic cells Heme oxygenase-1 Mitogen-activated protein kinases NRF2 SIGNALING
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Bacteroides forsythus ATCC43037菌体蛋白与人类唾液酸性富脯蛋白的相互作用
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作者 黄定明 周学东 天野敦雄 《口腔医学研究》 CAS CSCD 2003年第2期85-87,共3页
目的 :探讨福赛类杆菌与人类唾液富脯蛋白相互作用的蛋白分子。方法 :Western -blot方法。将人工合成唾液富脯蛋白用生物素标记 ,福赛类杆菌全菌蛋白凝胶电泳 ,半干转移至纤维膜上 ,观察二者的相互作用。结果 :富脯蛋白能与分子量为 85K... 目的 :探讨福赛类杆菌与人类唾液富脯蛋白相互作用的蛋白分子。方法 :Western -blot方法。将人工合成唾液富脯蛋白用生物素标记 ,福赛类杆菌全菌蛋白凝胶电泳 ,半干转移至纤维膜上 ,观察二者的相互作用。结果 :富脯蛋白能与分子量为 85KD、6 5KD、6 0KD、以及 49KD的福赛类杆菌蛋白发生结合。结论 :福赛类杆菌存在与人类唾液富脯蛋白相互结合的粘附素。 展开更多
关键词 牙周疾病 根尖周疾病 福赛类杆菌 富脯蛋白 WESTERN-BLOT法
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Extended role for insertion sequence elements in the antibiotic resistance of Bacteroides 被引量:1
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作者 József Sóki 《World Journal of Clinical Infectious Diseases》 2013年第1期1-12,共12页
The Bacteroides species are important micro-organisms, both in the normal physiology of the intestines and as frequent opportunistic anaerobic pathogens, with a deeply-rooted phylogenetic origin endowing them with som... The Bacteroides species are important micro-organisms, both in the normal physiology of the intestines and as frequent opportunistic anaerobic pathogens, with a deeply-rooted phylogenetic origin endowing them with some interesting biological features. Their prevalence in anaerobic clinical specimens is around 60%-80%, and they display the most numerous and highest rates of antibiotic resistance among all pathogenic anaerobes. In these antibiotic resistance mechanisms there is a noteworthy role for the insertion sequence(IS) elements, which are usually regarded as representatives of ‘selfish' genes; the IS elements of Bacteroides are usually capable of up-regulating the antibiotic resistance genes. These include the cep A(penicillin and cephalosporin), cfx A(cephamycin), cfi A(carbapenem), nim(metronidazole) and erm F(clindamycin) resistance genes. This is achieved by outwardoriented promoter sequences on the ISs. Although some representatives are well characterized, e.g., the resistance gene-IS element pairs in certain resistant strains, open questions remain in this field concerning a better understanding of the molecular biology of theantibiotic resistance mechanisms of Bacteroides, which will have clinical implications. 展开更多
关键词 Antibiotic resistance Antibiotic resistance genes bacteroides fragilis Insertion sequence elements
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Endophthalmitis caused by Bacteroides fragilis after pars plana vitrectomy and treatment approach
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作者 Hakan Yildirim Mehmet Balbaba +1 位作者 Turgut Yilmaz Zülal Asci Toraman 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2022年第1期44-46,共3页
Rationale:Endophthalmitis is an uncommon but serious ocular infection often resulting in probable visual loss.Bacteroides fragilis is a rare cause of endophthalmitis.Patient concerns:A 46-year-old male patient complai... Rationale:Endophthalmitis is an uncommon but serious ocular infection often resulting in probable visual loss.Bacteroides fragilis is a rare cause of endophthalmitis.Patient concerns:A 46-year-old male patient complained of eye pain and low vision after pars plana vitrectomy.Diagnosis:Bacteroides fragilis endophthalmitis after pars plana vitrectomy was diagnosed.Interventions:Pars plana vitrectomy and silicone oil implantation were performed.Outcomes:Early treatment and choice of tamponade in endophthalmitis after pars plana vitrectomy may possibly prevent evisceration and progression of endophthalmitis.Lessons:Bacteroides fragilis can be seen in cases of endophthalmitis after pars plana vitrectomy. 展开更多
关键词 bacteroides fragilis ENDOPHTHALMITIS Pars plana vitrectomy
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脆弱拟杆菌(Bacteroides fragilis)产肠毒素菌株和非产肠毒素菌株的抗原特性
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作者 Myers L.L. 胡贞延 《畜牧与饲料科学》 1989年第2期37-39,共3页
从腹泻犊牛(62株)、羔羊(2株)和猪(5株)的粪便中获得脆弱拟杆菌产肠毒素株(44株)和非产肠毒素株(25株)。利用微量全细胞凝集试验和凝胶双扩散试验检测,菌株对13株脆弱拟杆菌产肠毒素菌株制备的非吸收兔抗血清有反应。脆弱拟杆菌有多种... 从腹泻犊牛(62株)、羔羊(2株)和猪(5株)的粪便中获得脆弱拟杆菌产肠毒素株(44株)和非产肠毒素株(25株)。利用微量全细胞凝集试验和凝胶双扩散试验检测,菌株对13株脆弱拟杆菌产肠毒素菌株制备的非吸收兔抗血清有反应。脆弱拟杆菌有多种抗原。根据凝集反应,44株产肠毒素脆弱拟杆菌(ETBE)中有37株(84%)组成13个血清群、25株非产肠毒素脆弱拟杆菌(non—ETBF)中有14株(56%)组成13个血清群中的4个血清群。与凝胶扩散试验的结果比较,大部分菌株对13株抗血清有不同的凝集试验反应模式,从 non—ETBF 中不能区分ETBF。脆弱拟杆菌抗原的异源性促进了个别菌株的变异,这种能力对将来的流行病学和毒力研究是有益的。从腹泻犊牛、羔羊和猪的粪便中分离的ETBF,属于专性厌氧菌。利用肠结扎试验,证明脆弱拟杆菌在犊牛和羔羊中产生一种肠毒素,当给予新生羔羊口服时,证明 ETBF是腹泻病原。根据凝集和凝胶扩散分析,脆弱拟杆菌人株含有多种抗原,许多人株含有热稳定多糖荚膜抗原,可作为一种肠道外感染的毒力因子,有些脆弱拟杆菌人株也含有纤毛。本研究的目的,是根据抗原的不同,区分腹泻家畜的 ETBF 和 non—ETBF 的血清群,是否能从 non—ETBF 中区分 ETBF。 展开更多
关键词 脆弱拟杆菌 肠毒素 血清群 凝集试验 凝胶扩散试验 新生羔羊 bacteroidES 反应模式 凝集反应 肠道外感染
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Bacteroides fragilis Supernatant Extracts Enriched in Phenylacetic Acid Induce a Cytotoxic Effect in Mammalian Cells
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作者 Laís S.Falcao Eduardo N.F.Antunes +9 位作者 Eliane O.Ferreira Heidi Pauer Maria Teresa V.Romanos Rossiane C.Vommaro Sérgio H.Seabra Daniela S.Alviano Celuta S.Alviano Antonio Jorge R.da Silva Leandro A.Lobo Regina Maria C.P.Domingues 《Advances in Microbiology》 2015年第10期730-736,共7页
Bacteroides species are nearly half of the fecal flora community and some are host symbionts crucial to host nutrition and systemic immunity. Among Bacteroides species B. fragilis strains are considered to be the oppo... Bacteroides species are nearly half of the fecal flora community and some are host symbionts crucial to host nutrition and systemic immunity. Among Bacteroides species B. fragilis strains are considered to be the opportunistic ones, being the most isolated anaerobic bacteria in clinical samples. Cell-free supernatants of 65 B. fragilis strains were assayed and they were capable of inducing vacuolating phenotype on Vero cells lineage. The supernatant of the Bacteroides fragilis ATCC 23745 strain was elicited to have the strongest vacuolating effect on Vero cells monolayers and peritoneal macrophages. Some drastic cell alterations were observed, such as a general disorganization of cytoplasm and chromatin condensation, evidencing cell death. By transmission electron microscopy it was confirmed that the vacuoles observed were, in fact, swollen mitochondria. An immunocytochemical assay, TUNEL, was used to confirm this hypothesis and showed that Vero cells and peritoneal macrophages were dying by apoptotic process after exposition of B. fragilis cell-free supernatant. Physical analysis of the apoptotic factor has revealed properties similar to short-chain fatty acids. After gas chromatography and mass spectrometry analysis, phenylacetic acid (PA) was characterized as the major compound present in the most purified active fraction. We believe that the PA is responsible for the pro-apoptotic effect elicited by the supernatant of B. fragilis cultures. 展开更多
关键词 bacteroides fragilis Vacuolization APOPTOSIS Vero cells Lineage Peritoneal Macrophages Phenylacetic Acid
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Liquid chromatography-mass spectrometry analysis of major lipid species in Bacteroides thetaiotaomicron VPI 5482
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作者 Fenfang He Geer Liu +3 位作者 Danyang Huang Zhen Wang Aizhen Zhao Xiaoyuan Wang 《Systems Microbiology and Biomanufacturing》 2025年第1期409-420,共12页
Bacteroides thetaiotaomicron colonizes the human gastrointestinal tract and establishes a symbiotic relationship with the host,contributing to reducing intestinal inflammation and enhancing resistance against foreign ... Bacteroides thetaiotaomicron colonizes the human gastrointestinal tract and establishes a symbiotic relationship with the host,contributing to reducing intestinal inflammation and enhancing resistance against foreign pathogens.Recent reports have revealed that diverse lipid species such as glycerophospholipids,sphingolipids,and N-acyl amines exist in B.thetaiotaomicron and play essential roles in the immune process.In this research,total lipids obtained from B.thetaiotaomicron were purified via thin-layer chromatography,and the species and molecular structures of visible lipids in different hydrophobic regions were qualitatively characterized by high-performance liquid chromatography-mass spectrometry.The results indicated that seven lipid species were primarily displayed on the plate,including phosphatidylethanolamine,ethanolamine phosphoryl dihydroceramide,inositol phosphoryl dihydroceramide,glycyl-serine phosphoryl dihydroceramide,phosphatidylglycerol,cardiolipin,and glycyl-serine phosphoryl diacylglycerol.The phosphatidylethanolamine,ethanolamine phosphoryl dihydroceramide,and inositol phosphoryl dihydroceramide species corresponding to ion peaks at m/z 676.48,691.53,and 796.53 exhibited significantly high abundance compared to other species,suggesting their prevalent presence in total lipids.The molecular structures of phosphatidylethanolamine and ethanolamine phosphoryl dihydroceramide were derived from the modification of diacylglycerol and dihydroceramide with phosphoethanolamine,while the structure of inositol phosphoryl dihydroceramide was derived from the modification of dihydroceramide with phosphoinositol.The phosphatidylglycerol and cardiolipin species corresponding to m/z 721.51 and 1323.94 have been detected in the membrane lipids of B.thetaiotaomicron,although they were not mentioned in previous studies.These findings are important for understanding the molecular mechanisms of B.thetaiotaomicron colonization in mammalian gut. 展开更多
关键词 bacteroides thetaiotaomicron Sphingolipids Ceramide Phospholipid Lipid
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Essential roles of nodule cysteine-rich peptides in maintaining the viability of terminally differentiated bacteroids in legume-rhizobia symbiosis 被引量:1
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作者 Jian Yang Fengzhan Gao Huairong Pan 《Journal of Integrative Plant Biology》 2025年第4期1077-1085,共9页
Investigations into the nitrogen-fixing symbiosis between legumes and rhizobia can yield innovative strategies for sustainable agriculture.Legume species of the Inverted Repeat-Lacking Clade(IRLC)and the Dalbergioids,... Investigations into the nitrogen-fixing symbiosis between legumes and rhizobia can yield innovative strategies for sustainable agriculture.Legume species of the Inverted Repeat-Lacking Clade(IRLC)and the Dalbergioids,can utilize nodule cysteine-rich(NCR)peptides,a diverse family of peptides characterized by four or six highly conserved cysteine residues,to communicate with their microbial symbionts.These peptides,many of which exhibit antimicrobial properties,induce profound differentiation of bacteroids(semi-autonomous forms of bacteria)within nodule cells.This terminal differentiation endows the bacteroids with the ability to fix nitrogen,at the expense of their reproductive capacity.Notably,a significant number of NCR peptides is expressed in the nodule fixation zone,where the bacteroids have already reached terminal differentiation.Recent discoveries,through forward genetics approaches,have revealed that the functions of NCR peptides extend beyond antimicrobial effects and the promotion of differentiation.They also play a critical role in sustaining the viability of terminally differentiated bacteroids within nodule cells.These findings underscore the multifaceted functions of NCR peptides and highlight the importance of these peptides in mediating communications between host cells and the terminally differentiated bacteroids. 展开更多
关键词 legume-rhizobia symbiosis NCR peptides terminal bacteroid differentiation
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Bacteroides fragilis-derived succinic acid promotes the degradation of uric acid by inhibiting hepatic AMPD2:Insight into how plant-based berberine ameliorates hyperuricemia
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作者 Libin Pan Ru Feng +17 位作者 Jiachun Hu Hang Yu Qian Tong Xinyu Yang Jianye Song Hui Xu Mengliang Ye Zhengwei Zhang Jie Fu Haojian Zhang Jinyue Lu Zhao Zhai Jingyue Wang Yi Zhao Hengtong Zuo Xiang Hui Jiandong Jiang Yan Wang 《Acta Pharmaceutica Sinica B》 2025年第10期5244-5260,共17页
In recent decades,the prevalence of hyperuricemia and gout has increased dramatically due to lifestyle changes.The drugs currently recommended for hyperuricemia are associated with adverse reactions that limit their c... In recent decades,the prevalence of hyperuricemia and gout has increased dramatically due to lifestyle changes.The drugs currently recommended for hyperuricemia are associated with adverse reactions that limit their clinical use.In this study,we report that berberine(BBR)is an effective drug candidate for the treatment of hyperuricemia,with its mechanism potentially involving the modulation of gut microbiota and its metabolite,succinic acid.BBR has demonstrated good therapeutic effects in both acute and chronic animal models of hyperuricemia.In a clinical trial,oral administration of BBR for 6 months reduced blood uric acid levels in 22 participants by modulating the gut microbiota,which led to an increase in the abundance of Bacteroides and a decrease in Clostridium sensu stricto_1.Furthermore,Bacteroides fragilis was transplanted into ICR mice,and the results showed that Bacteroides fragilis exerted a therapeutic effect on uric acid similar to that of BBR.Notably,succinic acid,a metabolite of Bacteroides,significantly reduced uric acid levels.Subsequent cell and animal experiments revealed that the intestinal metabolite,succinic acid,regulated the upstream uric acid synthesis pathway in the liver by inhibiting adenosine monophosphate deaminase 2(AMPD2),an enzyme responsible for converting adenosine monophosphate(AMP)to inosine monophosphate(IMP).This inhibition resulted in a decrease in IMP levels and an increase in phosphate levels.The reduction in IMP led to a decreased downstream production of hypoxanthine,xanthine,and uric acid.BBR also demonstrated excellent renoprotective effects,improving nephropathy associated with hyperuricemia.In summary,BBR has the potential to be an effective treatment for hyperuricemia through the gut-liver axis. 展开更多
关键词 BERBERINE HYPERURICEMIA Gut microbiota AMPD2 Succinic acid Uric acid synthesis Gut-liver axis bacteroides fragilis
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Lower abundance of Bacteroides and metabolic dysfunction are highly associated with the post-weaning diarrhea in piglets 被引量:7
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作者 Wen Ren Bing Yu +9 位作者 Jie Yu Ping Zheng Zhiqing Huang Junqiu Luo Xiangbing Mao Jun He Hui Yan Jinlong Wu Daiwen Chen Yuheng Luo 《Science China(Life Sciences)》 SCIE CAS CSCD 2022年第10期2062-2075,共14页
Growing evidences show a direct link between diarrhea and disorders of gut microbiota in pigs.However,whether there are microbial markers associated with post-weaning diarrhea remains unknown.In the current study,we c... Growing evidences show a direct link between diarrhea and disorders of gut microbiota in pigs.However,whether there are microbial markers associated with post-weaning diarrhea remains unknown.In the current study,we compared the microbial community,functions and metabolites between healthy weaned piglets(group H,n=7)and piglets with post-weaning diarrhea(group D,n=7),in order to find out diarrhea associated microbial markers.Each of 7 fecal samples was collected from H and D piglets(weaned at 21 d and sampled at 26 d).The metagenomic and untargeted metabolomic analysis revealed that the microbial composition,function and metabolic profile in D pigs was considerably reshaped,including the reduced abundance and number of Bacteroides,which significantly correlated with the diarrhea status of host.The carbohydrate metabolism,biosynthesis and metabolism,lipid metabolism,amino acid metabolism,and the activity of glycan and carbohydrates digestion related enzymes showed extensively down-regulated in D pigs compared with H pigs.Diarrhea significantly changed the metabolic profiles of fecal microbiota,and most of the altered metabolites were negatively or positively correlated with the change in the abundance of Bacteroides.In conclusion,the lower abundance of Bacteroides and its associated metabolic dysfunction may be regarded as microbial markers of physiological post-weaning diarrhea in piglets. 展开更多
关键词 post-weaning piglet DIARRHEA bacteroidES metabolic dysfunction commensal microbiota
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Bacteroides ovatus-mediated CD27^(−)MAIT cell activation is associated with obesity-related T2D progression 被引量:2
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作者 Yue Li Yi Yang +18 位作者 Jin Wang Peihong Cai Mei Li Xixiang Tang Ying Tan Yuchan Wang Fan Zhang Xiaofeng Wen Qiaoxing Liang Yuanpeng Nie Tufeng Chen Xiang Peng Xuemin He Yanhua Zhu Guojun Shi Wai WCheung Lai Wei Yanming Chen Yan Lu 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2022年第7期791-804,共14页
Type 2 diabetes(T2D)is highly associated with obesity.However,the factors that drive the transition from excessive weight gain to glucose metabolism disruption are still uncertain and seem to revolve around systemic i... Type 2 diabetes(T2D)is highly associated with obesity.However,the factors that drive the transition from excessive weight gain to glucose metabolism disruption are still uncertain and seem to revolve around systemic immune disorder.Mucosal-associated invariant T(MAIT)cells,which are innate-like T cells that recognize bacterial metabolites,have been reported to be altered in obese people and to lead to metabolic dysfunction during obesity.By studying the immunophenotypes of blood MAIT cells from a cross-sectional cohort of obese participants with/without T2D,we found an elevation in CD27^(-)negative(CD27−)MAIT cells producing a high level of IL-17 under T2D obese conditions,which could be positively correlated with impaired glucose metabolism in obese people.We further explored microbial translocation caused by gut barrier dysfunction in obese people as a triggering factor of MAIT cell abnormalities.Specifically,accumulation of the bacterial strain Bacteroides ovatus in the peripheral blood drove IL-17^(-)producing CD27−MAIT cell expansion and could be associated with T2D risk in obese individuals.Overall,these results suggest that an aberrant gut microbiota–immune axis in obese people may drive or exacerbate T2D.Importantly,CD27−MAIT cell subsets and Bacteroides ovatus could represent targets for novel interventional strategies.Our findings extend current knowledge regarding the clinical relevance of body mass index(BMI)-associated variation in circulating MAIT cells to reveal the role of these cells in obesity-related T2D progression and the underlying cellular mechanisms. 展开更多
关键词 type 2 diabetes OBESITY MAIT cells bacteroides ovatus bacterial translocation
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Cryo-EM structure of L-fucokinase/GDP-fucose pyrophosphorylase(FKP)in Bacteroides fragilis 被引量:1
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作者 Ying Liu Huifang Hu +6 位作者 Jia Wang Qiang Zhou Peng Wu Nieng Yan Hong-Wei Wang Jia-Wei Wu Linfeng Sun 《Protein & Cell》 SCIE CAS CSCD 2019年第5期365-369,共5页
Dear Editor,L-Fucose(6-deoxy-L-galactose,fucose)is the basic compone nt of a variety of glyca n structures.The fucosylated oligosaccharides participate in a variety of cellular activities,like the cell-cell recognitio... Dear Editor,L-Fucose(6-deoxy-L-galactose,fucose)is the basic compone nt of a variety of glyca n structures.The fucosylated oligosaccharides participate in a variety of cellular activities,like the cell-cell recognition,selectin-mediated leukocyteendothelial adhesion and the formation of Lewis blood group antigens(Ma et al.,2006).GDP-fucose is an important fucose donor in the process of fucosylated oligosaccharides formation.Two pathways of GDP-fucose synthesis are present in the cytosol of mammalian cells,including the de novo pathway and the salvage pathway(Becker et al.,2003).In the salvage pathway,cells use fucose from the extracellular or lysosomal sources to synthesize GDP-fucose. 展开更多
关键词 CRYO-EM STRUCTURE PYROPHOSPHORYLASE bacteroidES fragilis
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A randomized trial of Bacteroides fragilis 839 on preventing chemotherapy-induced myelosuppression and gastrointestinal adverse effects in breast cancer patients 被引量:2
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作者 Ting Zeng Yu-hong Deng +7 位作者 Chu-hui Lin Xin-xin Chen Hai-xia Jia Xiao-wu Hu Ting Xia Yun Ling Le-hong Zhang Teng-fei Cao 《Asia Pacific Journal of Clinical Nutrition》 2024年第1期23-32,共10页
Background and Objectives:To evaluate the potential benefits of Bacteroides fragilis 839(BF839),a nextgeneration probiotics,in reducing myelosuppression and gastrointestinal toxicity associated with chemotherapy in br... Background and Objectives:To evaluate the potential benefits of Bacteroides fragilis 839(BF839),a nextgeneration probiotics,in reducing myelosuppression and gastrointestinal toxicity associated with chemotherapy in breast cancer patient.Methods and Study Design:40 women with early breast cancer were randomly assigned to the BF839(n=20)or placebo(n=20)during the administration of adjuvant chemotherapy(4 cycles of epirubicin 100mg/m^(2) and cyclophosphamide 600mg/m^(2)).Myelosuppression and gastrointestinal adverse effects were monitored in both groups.Results:Throughout the four treatment cycles,the percentage of patients experiencing myelosuppression was 42.5%in the BF839 group,significantly lower than the 66.3%observed in the control group(p=0.003).Two patients in the BF839 group and three patients in the placebo group received recombinant human granulocyte colony-stimulating factor(rhG-CSF)due to leukopenia/neutropenia.When considering an ITT analysis,which included all patients regardless of rhG-CSF treatment,the BF839 group exhibited less reduction from baseline in white blood cells(-0.31±1.19 vs-1.15±0.77,p=0.012)and neutrophils(0.06±1.00 vs-0.84±0.85,p=0.004)compared to the placebo group.The difference became even more significant when excluding the patients who received rhG-CSF injections.Throughout the four treatment cycles,compared to the placebo group,the BF839 group had significantly lower rates of 3-4 grade nausea(35.0%vs 71.3%,p=0.001),vomiting(20.0%vs 45.0%,p=0.001),and diarrhea(15.0%vs 30.0%,p=0.023).Conclusions:These findings suggest that BF839 has the potential to effectively mitigate myelosuppression and gastrointestinal toxicity associated with chemotherapy in breast cancer patients. 展开更多
关键词 bacteroides fragilis PREVENTION CHEMOTHERAPY MYELOSUPPRESSION
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Expression of enterotoxigenic Bacteroides fragilis and polyketide synthase gene-expressing Escherichiacoli in colorectal adenoma patients
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作者 解玲玲 《China Medical Abstracts(Internal Medicine)》 2016年第2期40-41,共2页
Objective To investigate the distribution of various bacteria in adenoma tissue of colorectal adenoma(T/CRA),normal colonic mucosa tissue adjacent to the adenoma(N/CRA),and healthy colonic mucosa tissue(N/H)by compari... Objective To investigate the distribution of various bacteria in adenoma tissue of colorectal adenoma(T/CRA),normal colonic mucosa tissue adjacent to the adenoma(N/CRA),and healthy colonic mucosa tissue(N/H)by comparing the number of total bacteria,Bacteroides fragilis(BF),enterotoxigenic Bacteroides 展开更多
关键词 bacteroidES ADENOMA colorectal MUCOSA colonic EXPRESSING colonoscopy Peking markedly tumorigenesis
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