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[PMID]:29458539
[Au] Autor:Ma ST; Ding GJ; Huang XW; Wang ZW; Wang L; Yu ML; Shi W; Jiang YP; Tang LJ; Xu YG; Li YJ
[Ad] Endereço:College of Veterinary Medicine, Northeast Agricultural University, Mu Cai Street No. 59, Xiang Fang District, Harbin, PR China.
[Ti] Título:Immunogenicity in chickens with orally administered recombinant chicken-borne Lactobacillus saerimneri expressing FimA and OmpC antigen of O78 avian pathogenic Escherichia coli.
[So] Source:J Med Microbiol;67(3):441-451, 2018 Mar.
[Is] ISSN:1473-5644
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:PURPOSE: Avian colibacillosis is responsible for economic losses to poultry producers worldwide. To combat this, we aimed to develop an effective oral vaccine for chicken against O78 avian pathogenic Escherichia coli (APEC) infection through a Lactobacillus delivery system. METHODOLOGY: Eight Lactobacillus strains isolated from the intestines of broiler chickens were evaluated based on their in vitro adherence ability to assess their potential as a delivery vector. Fimbrial subunit A (FimA) and outer-membrane protein C (OmpC) of APEC with and without fusion to dendritic cell-targeting peptide (DCpep) and microfold cell-targeting peptide (Co1) were displayed on the surface of Lactobacillus saerimneri M-11 and yielded vaccine groups (pPG-ompC-fimA/M-11 and pPG-ompC-fimA-Co1-DCpep/M-11, respectively). The colonization of the recombinant strains in vivo was assessed and the immunogenicity and protective efficacy of orally administered recombinant strains in chickens were evaluated. RESULTS: The colonization of the recombinant strains in vivo revealed no significant differences between the recombinant and wild-type strains. Chickens orally administered with vaccine groups showed significantly higher levels of OmpC/FimA-specific IgG in serum and mucosal IgA in cecum lavage, nasal lavage and stool compared to the pPG/M-11 group. After challenge with APEC CVCC1553, better protective efficacy was observed in chickens orally immunized with pPG-ompC-fimA/M-11 and pPG-ompC-fimA-Co1-DCpep/M-11, but no significant differences were observed between the two groups. CONCLUSIONS: Recombinant chicken-borne L. saerimneri M-11 showed good immunogenicity in chickens, suggesting that it may be a promising vaccine candidate against APEC infections. However, the activity of mammalian DCpep and Co1 was not significant in chickens.
[Mh] Termos MeSH primário: Infecções por Escherichia coli/veterinária
Vacinas contra Escherichia coli/imunologia
Proteínas de Fímbrias/imunologia
Imunogenicidade da Vacina
Lactobacillus/genética
Porinas/imunologia
Doenças das Aves Domésticas/imunologia
[Mh] Termos MeSH secundário: Administração Oral
Animais
Anticorpos Antibacterianos/sangue
Antígenos de Bactérias/genética
Antígenos de Bactérias/imunologia
Ceco/imunologia
Galinhas
Escherichia coli/imunologia
Escherichia coli/patogenicidade
Infecções por Escherichia coli/imunologia
Infecções por Escherichia coli/prevenção & controle
Proteínas de Fímbrias/genética
Imunoglobulina A/sangue
Imunoglobulina G/sangue
Intestinos/microbiologia
Lactobacillus/crescimento & desenvolvimento
Lactobacillus/imunologia
Lactobacillus/isolamento & purificação
Porinas/genética
Doenças das Aves Domésticas/prevenção & controle
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Bacterial); 0 (Antigens, Bacterial); 0 (Escherichia coli Vaccines); 0 (Immunoglobulin A); 0 (Immunoglobulin G); 0 (OmpC protein); 0 (Porins); 0 (fimbrillin); 147680-16-8 (Fimbriae Proteins)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180221
[St] Status:MEDLINE
[do] DOI:10.1099/jmm.0.000679


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[PMID]:29247504
[Au] Autor:Gallegos-Tabanico A; Sarabia-Sainz JA; Sarabia-Sainz HM; Carrillo Torres R; Guzman-Partida AM; Monfort GR; Silva-Campa E; Burgara-Estrella AJ; Angulo-Molina A; Acosta-Elias M; Pedroza-Montero M; Vazquez-Moreno L
[Ad] Endereço:Departamento de Física, Universidad de Sonora, Hermosillo, Sonora, 83000, México.
[Ti] Título:Molecular recognition of glyconanoparticles by RCA and E. coli K88 - designing transports for targeted therapy.
[So] Source:Acta Biochim Pol;64(4):671-677, 2017.
[Is] ISSN:1734-154X
[Cp] País de publicação:Poland
[La] Idioma:eng
[Ab] Resumo:The targeted drug delivery has been studied as one of the main methods in medicine to ensure successful treatments of diseases. Pharmaceutical sciences are using micro or nano carriers to obtain a controlled delivery of drugs, able to selectively interact with pathogens, cells or tissues. In this work, we modified bovine serum albumin (BSA) with lactose, obtaining a neoglycan (BSA-Lac). Subsequently, we synthesized glyconanoparticles (NPBSA-Lac) with the premise that it would be recognized by microbial galactose specific lectins. NPBSA-Lac were tested for bio-recognition with adhesins of E. coli K88 and Ricinus communis agglutinin I (RCA). Glycation of BSA with lactose was analyzed by electrophoresis, infrared spectroscopy and fluorescence. Approximately 41 lactoses per BSA molecule were estimated. Nanoparticles were obtained using water in oil emulsion method and spheroid morphology with a range size of 300-500 nm was observed. Specific recognition of NPBSA-Lac by RCA and E. coli K88 was displayed by aggregation of nanoparticles analyzed by dynamic light scattering and atomic force microscopy. The results indicate that the lactosylated nanovectors could be targeted at the E. coli K88 adhesin and potentially could be used as a transporter for an antibacterial drug.
[Mh] Termos MeSH primário: Antígenos de Bactérias/metabolismo
Portadores de Fármacos/metabolismo
Proteínas de Escherichia coli/metabolismo
Proteínas de Fímbrias/metabolismo
Nanopartículas/química
Lectinas de Plantas/metabolismo
[Mh] Termos MeSH secundário: Portadores de Fármacos/química
Eletroforese em Gel de Poliacrilamida
Escherichia coli/metabolismo
Lactose/química
Microscopia de Força Atômica
Peso Molecular
Tamanho da Partícula
Soroalbumina Bovina/química
Espectrofotometria Infravermelho
Espectroscopia de Infravermelho com Transformada de Fourier
Triptofano/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antigens, Bacterial); 0 (Drug Carriers); 0 (Escherichia coli Proteins); 0 (K88 antigen, E coli); 0 (Plant Lectins); 0 (Ricinus communis agglutinin-1); 147680-16-8 (Fimbriae Proteins); 27432CM55Q (Serum Albumin, Bovine); 8DUH1N11BX (Tryptophan); J2B2A4N98G (Lactose)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171217
[St] Status:MEDLINE
[do] DOI:10.18388/abp.2017_1639


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[PMID]:29176857
[Au] Autor:Pan S; Liu Y; Si Y; Zhang Q; Wang L; Liu J; Wang C; Xiao S
[Ad] Endereço:Department of Orthodontics, School of Stomatology, Shandong University, Jinan, China.
[Ti] Título:Prevalence of fimA genotypes of Porphyromonas gingivalis in adolescent orthodontic patients.
[So] Source:PLoS One;12(11):e0188420, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The placement of fixed orthodontic appliances may alter the composition of oral microbiota and has the potential risk of periodontal complication. Porphyromonas gingivalis fimbriae play a critical role in colonization of P. gingivalis in subgingival regions. In this study, we investigated the association between the prevalence of P. gingivalis-specific fimA genotypes and periodontal health status in adolescent orthodontic patients, to identify the pathogencity of P. gingivalis during orthodontic therapy. METHODS: Sixty-one adolescent orthodontic patients were enrolled in the case group, while the control group consisted of 56 periodontally healthy adolescents. At baseline (T0), clinical parameter (gingival index) was tested, and subgingival plaque samples were obtained from the lower incisors. The incidences of P. gingivalis and fimA genotypes were detected by polymerase chain reaction. All parameters were reassessed after 1 month (T1), 2 months (T2), 3 months (T3), and 6 months (T4) in the case group and then compared with those of the controls. RESULTS: Both microbiological and clinical parameters from orthodontic patients started to increase after placement of fixed appliances. Maximum values were reached at 3 months after placement and followed by their decreases at six months. However, the microbiological and clinical parameters in the case group were significantly higher than those of the control group. The GI of fimA II, IV-positive samples was significantly higher than that of negative samples. CONCLUSION: P. gingivalis carrying fimA II or IV was closely related to orthodontic gingivitis. In addition, proper oral hygiene control could lead to little increase in dental plaque accumulation, and exert a beneficial effect to periodontal tissues.
[Mh] Termos MeSH primário: Proteínas de Fímbrias/genética
Aparelhos Ortodônticos/microbiologia
Porphyromonas gingivalis/genética
[Mh] Termos MeSH secundário: Adolescente
Estudos de Casos e Controles
Feminino
Genótipo
Seres Humanos
Masculino
Índice Periodontal
Reação em Cadeia da Polimerase
Prevalência
RNA Ribossômico 16S/genética
Reprodutibilidade dos Testes
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Ribosomal, 16S); 147680-16-8 (Fimbriae Proteins)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171219
[Lr] Data última revisão:
171219
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171128
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0188420


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[PMID]:29016622
[Au] Autor:Lamb JJ; Hohmann-Marriott MF
[Ad] Endereço:Department of Biotechnology & PhotoSynLab, NTNU, Trondheim, Norway.
[Ti] Título:Manganese acquisition is facilitated by PilA in the cyanobacterium Synechocystis sp. PCC 6803.
[So] Source:PLoS One;12(10):e0184685, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Manganese is an essential element required by cyanobacteria, as it is an essential part of the oxygen-evolving center of photosystem II. In the presence of atmospheric oxygen, manganese is present as manganese oxides, which have low solubility and consequently provide low bioavailability. It is unknown if cyanobacteria are able to utilize these manganese sources, and what mechanisms may be employed to do so. Recent evidence suggests that type IV pili in non-photosynthetic bacteria facilitate electron donation to extracellular electron acceptors, thereby enabling metal acquisition. Our present study investigates whether PilA1 (major pilin protein of type IV pili) enables the cyanobacterium Synechocystis PCC 6808 to access to Mn from manganese oxides. We present physiological and spectroscopic data, which indicate that the presence of PilA1 enhances the ability of cyanobacteria to grow on manganese oxides. These observations suggest a role of PilA1-containing pili in cyanobacterial manganese acquisition.
[Mh] Termos MeSH primário: Cianobactérias/genética
Proteínas de Fímbrias/genética
Fímbrias Bacterianas/metabolismo
Manganês/metabolismo
[Mh] Termos MeSH secundário: Cianobactérias/crescimento & desenvolvimento
Cianobactérias/metabolismo
Proteínas de Fímbrias/metabolismo
Fímbrias Bacterianas/genética
Compostos de Manganês/metabolismo
Óxidos/metabolismo
Oxigênio/metabolismo
Complexo de Proteína do Fotossistema II/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Manganese Compounds); 0 (Oxides); 0 (Photosystem II Protein Complex); 147680-16-8 (Fimbriae Proteins); 42Z2K6ZL8P (Manganese); 64J2OA7MH3 (manganese oxide); S88TT14065 (Oxygen)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171011
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0184685


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[PMID]:28808163
[Au] Autor:Poole NM; Green SI; Rajan A; Vela LE; Zeng XL; Estes MK; Maresso AW
[Ad] Endereço:Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA.
[Ti] Título:Role for FimH in Extraintestinal Pathogenic Escherichia coli Invasion and Translocation through the Intestinal Epithelium.
[So] Source:Infect Immun;85(11), 2017 Nov.
[Is] ISSN:1098-5522
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The translocation of bacteria across the intestinal epithelium of immunocompromised patients can lead to bacteremia and life-threatening sepsis. Extraintestinal pathogenic (ExPEC), so named because this pathotype infects tissues distal to the intestinal tract, is a frequent cause of such infections, is often multidrug resistant, and chronically colonizes a sizable portion of the healthy population. Although several virulence factors and their roles in pathogenesis are well described for ExPEC strains that cause urinary tract infections and meningitis, they have not been linked to translocation through intestinal barriers, a fundamentally distant yet important clinical phenomenon. Using untransformed human intestinal enteroids and transformed Caco-2 cells, we report that ExPEC strain CP9 binds to and invades the intestinal epithelium. ExPEC harboring a deletion of the gene encoding the mannose-binding type 1 pilus tip protein FimH demonstrated reduced binding and invasion compared to strains lacking known virulence factors. Furthermore, in a murine model of chemotherapy-induced translocation, ExPEC lacking colonized at levels comparable to that of the wild type but demonstrated a statistically significant reduction in translocation to the kidneys, spleen, and lungs. Collectively, this study indicates that FimH is important for ExPEC translocation, suggesting that the type 1 pilus is a therapeutic target for the prevention of this process. Our study also highlights the use of human intestinal enteroids in the study of enteric diseases.
[Mh] Termos MeSH primário: Adesinas de Escherichia coli/genética
Translocação Bacteriana/genética
Células Epiteliais/microbiologia
Infecções por Escherichia coli/microbiologia
Escherichia coli Extraintestinal Patogênica/patogenicidade
Proteínas de Fímbrias/genética
Fímbrias Bacterianas/fisiologia
[Mh] Termos MeSH secundário: Animais
Células CACO-2
Células Epiteliais/patologia
Infecções por Escherichia coli/patologia
Escherichia coli Extraintestinal Patogênica/fisiologia
Feminino
Proteínas de Fímbrias/deficiência
Expressão Gênica
Seres Humanos
Jejuno/microbiologia
Jejuno/patologia
Rim/microbiologia
Rim/patologia
Pulmão/microbiologia
Pulmão/patologia
Masculino
Camundongos Endogâmicos BALB C
Cultura Primária de Células
Esferoides Celulares/microbiologia
Esferoides Celulares/patologia
Baço/microbiologia
Baço/patologia
Virulência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Adhesins, Escherichia coli); 0 (fimH protein, E coli); 147680-16-8 (Fimbriae Proteins)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170816
[St] Status:MEDLINE


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[PMID]:28771515
[Au] Autor:Leong CG; Bloomfield RA; Boyd CA; Dornbusch AJ; Lieber L; Liu F; Owen A; Slay E; Lang KM; Lostroh CP
[Ad] Endereço:Department of Molecular Biology, Colorado College, Colorado Springs, Colorado, United States of America.
[Ti] Título:The role of core and accessory type IV pilus genes in natural transformation and twitching motility in the bacterium Acinetobacter baylyi.
[So] Source:PLoS One;12(8):e0182139, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Here we present an examination of type IV pilus genes associated with competence and twitching in the bacterium Acinetobacter baylyi (strain ADP1, BD413). We used bioinformatics to identify potential competence and twitching genes and their operons. We measured the competence and twitching phenotypes of the bioinformatically-identified genes. These results demonstrate that competence and twitching in A. baylyi both rely upon a core of the same type IV pilus proteins. The core includes the inner membrane assembly platform (PilC), a periplasmic assemblage connecting the inner membrane assembly platform to the secretin (ComM), a secretin (ComQ) and its associated pilotin (PilF) that assists with secretin assembly and localization, both cytoplasmic pilus retraction ATPases (PilU, PilT), and pilins (ComP, ComB, PilX). Proteins not needed for both competence and twitching are instead found to specialize in either of the two traits. The pilins are varied in their specialization with some required for either competence (FimT) and others for twitching (ComE). The protein that transports DNA across the inner membrane (ComA) specializes in competence, while signal transduction proteins (PilG, PilS, and PilR) specialize in twitching. Taken together our results suggest that the function of accessory proteins should not be based on homology alone. In addition the results suggest that in A. baylyi the mechanisms of natural transformation and twitching are mediated by the same set of core Type IV pilus proteins with distinct specialized proteins required for each phenotype. Finally, since competence requires multiple pilins as well as both pilus retraction motors PilU and PilT, this suggests that A. baylyi employs a pilus in natural transformation.
[Mh] Termos MeSH primário: Acinetobacter/genética
Acinetobacter/metabolismo
Proteínas de Fímbrias/metabolismo
Transformação Bacteriana/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
DNA Bacteriano/isolamento & purificação
DNA Bacteriano/metabolismo
Proteínas de Fímbrias/química
Proteínas de Fímbrias/genética
Fímbrias Bacterianas/genética
Teste de Complementação Genética
Proteínas de Membrana Transportadoras/química
Proteínas de Membrana Transportadoras/genética
Proteínas de Membrana Transportadoras/metabolismo
Fenótipo
Alinhamento de Sequência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (DNA, Bacterial); 0 (Membrane Transport Proteins); 147680-16-8 (Fimbriae Proteins)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170804
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0182139


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[PMID]:28762293
[Au] Autor:Sivignon A; Bouckaert J; Bernard J; Gouin SG; Barnich N
[Ad] Endereço:a M2iSH, UMR 1071 Inserm, INRA USC-2018 , Institut Universitaire Technologique, Université Clermont Auvergne , Clermont-Ferrand 63001 , France.
[Ti] Título:The potential of FimH as a novel therapeutic target for the treatment of Crohn's disease.
[So] Source:Expert Opin Ther Targets;21(9):837-847, 2017 Sep.
[Is] ISSN:1744-7631
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:INTRODUCTION: Crohn's disease (CD) is a life-long chronic disorder characterized by intestinal inflammation. Current treatments for CD are directed towards abnormal immune responses rather than the intestinal bacteria that trigger intestinal inflammation. Areas covered: Adherent-Invasive Escherichia coli (AIEC) bacteria abnormally colonize the ileal mucosa in a subgroup of CD patients. They can promote or perpetuate chronic inflammation and are therefore an interesting therapeutic target. Various strategies that target these E. coli strains have been developed to promote their intestinal clearance. Here, we review current AIEC-targeted strategies, especially anti-adhesive strategies, that are based on the development of FimH antagonists. We discuss their potential as personalized microbiota-targeted treatments for CD patients abnormally colonized by AIEC. Expert opinion: A large panel of mannose-derived FimH antagonists were tested for their ability to inhibit E. coli adhesion to host cells. Documented reports suggest that monovalent mannosides are promising candidates that could represent a complementary therapeutic strategy to prevent intestinal inflammation in the E. coli-colonized CD patient subgroup. Ongoing research continues to improve the pharmacokinetic properties of mannosides, and hopefully, clinical trials will be performed in CD patients in the near future.
[Mh] Termos MeSH primário: Doença de Crohn/tratamento farmacológico
Infecções por Escherichia coli/tratamento farmacológico
Proteínas de Fímbrias/antagonistas & inibidores
[Mh] Termos MeSH secundário: Adesinas de Escherichia coli
Animais
Doença de Crohn/microbiologia
Doença de Crohn/patologia
Desenho de Drogas
Escherichia coli/isolamento & purificação
Infecções por Escherichia coli/fisiopatologia
Seres Humanos
Inflamação/tratamento farmacológico
Inflamação/microbiologia
Inflamação/patologia
Manosídeos/administração & dosagem
Manosídeos/farmacocinética
Terapia de Alvo Molecular
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Adhesins, Escherichia coli); 0 (Mannosides); 0 (fimH protein, E coli); 147680-16-8 (Fimbriae Proteins)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170904
[Lr] Data última revisão:
170904
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170802
[St] Status:MEDLINE
[do] DOI:10.1080/14728222.2017.1363184


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[PMID]:28739804
[Au] Autor:Pilipczuk J; Zalewska-Piatek B; Bruzdziak P; Czub J; Wieczór M; Olszewski M; Wanarska M; Nowicki B; Augustin-Nowacka D; Piatek R
[Ad] Endereço:From the Departments of Molecular Biotechnology and Microbiology and.
[Ti] Título:Role of the disulfide bond in stabilizing and folding of the fimbrial protein DraE from uropathogenic .
[So] Source:J Biol Chem;292(39):16136-16149, 2017 Sep 29.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Dr fimbriae are homopolymeric adhesive organelles of uropathogenic composed of DraE subunits, responsible for the attachment to host cells. These structures are characterized by enormously high stability resulting from the structural properties of an Ig-like fold of DraE. One feature of DraE and other fimbrial subunits that makes them peculiar among Ig-like domain-containing proteins is a conserved disulfide bond that joins their A and B strands. Here, we investigated how this disulfide bond affects the stability and folding/unfolding pathway of DraE. We found that the disulfide bond stabilizes self-complemented DraE (DraE-sc) by ∼50 kJ mol in an exclusively thermodynamic manner, by lowering the free energy of the native state and with almost no effect on the free energy of the transition state. This finding was confirmed by experimentally determined folding and unfolding rate constants of DraE-sc and a disulfide bond-lacking DraE-sc variant. Although the folding of both proteins exhibited similar kinetics, the unfolding rate constant changed upon deletion of the disulfide bond by 10 orders of magnitude, from ∼10 s to 10 s Molecular simulations revealed that unfolding of the disulfide bond-lacking variant is initiated by strands A or G and that disulfide bond-mediated joining of strand A to the core strand B cooperatively stabilizes the whole protein. We also show that the disulfide bond in DraE is recognized by the DraB chaperone, indicating a mechanism that precludes the incorporation of less stable, non-oxidized DraE forms into the fimbriae.
[Mh] Termos MeSH primário: Adesinas Bacterianas/metabolismo
Cistina/química
Proteínas de Escherichia coli/metabolismo
Proteínas de Fímbrias/metabolismo
Modelos Moleculares
Escherichia coli Uropatogênica/fisiologia
[Mh] Termos MeSH secundário: Adesinas Bacterianas/química
Adesinas Bacterianas/genética
Sequência de Aminoácidos
Substituição de Aminoácidos
Aderência Bacteriana
Linhagem Celular Tumoral
Sequência Conservada
Cisteína/química
Transferência de Energia
Proteínas de Escherichia coli/química
Proteínas de Escherichia coli/genética
Proteínas de Fímbrias/química
Proteínas de Fímbrias/genética
Seres Humanos
Cinética
Simulação de Dinâmica Molecular
Mutação
Oxirredução
Conformação Proteica
Dobramento de Proteína
Redobramento de Proteína
Estabilidade Proteica
Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Adhesins, Bacterial); 0 (DraE protein, E coli); 0 (Escherichia coli Proteins); 0 (Recombinant Proteins); 147680-16-8 (Fimbriae Proteins); 48TCX9A1VT (Cystine); K848JZ4886 (Cysteine)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170726
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.785477


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[PMID]:28732013
[Au] Autor:Luo M; Yang S; Li X; Liu P; Xue J; Zhou X; Su K; Xu X; Qing Y; Qiu J; Li Y
[Ad] Endereço:School of Public Health and Management, Chongqing Medical University, Chongqing, China.
[Ti] Título:The KP1_4563 gene is regulated by the cAMP receptor protein and controls type 3 fimbrial function in Klebsiella pneumoniae NTUH-K2044.
[So] Source:PLoS One;12(7):e0180666, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Klebsiella pneumoniae (K. pneumoniae) is an opportunistic pathogen that can adhere to host cells or extracellular matrix via type 1 and type 3 fimbriae. KP1_4563 is a gene encoding a hypothetical protein in K. pneumoniae NTUH-K2044. KP1_4563 is located between the type 1 and type 3 fimbrial gene clusters and is likely associated with fimbrial function given its putative conserved domains of unknown function (DUF1471). Cyclic AMP receptor protein (CRP) regulates virulence-related gene expression and is a crucial transcriptional regulator in many bacteria. The predicted DNA recognition motif of CRP is present in the KP1_4563 promoter region. This study aimed to investigate the function of KP1_4563 in fimbriae and its transcriptional regulation mechanism by CRP. We generated Kp-Δ4563 mutant and complementation strains. We utilized phenotype and adhesion assays to evaluate the role of KP1_4563 in fimbriae. We conducted quantitative RT-PCR (qRT-PCR), LacZ fusion, electrophoretic mobility shift, and DNase I footprinting assays to study the transcriptional regulation of KP1_4563 gene by CRP. We found that KP1_4563 negatively regulates the function of type 3 fimbriae. Compared with NTUH-K2044, the absence of KP1_4563 enhanced the ability of Kp-Δ4563 to adhere to A549 cells. CRP negatively regulates KP1_4563 by directly binding to its promoter region. KP1_4563 plays an important role in type 3 fimbrial function. This novel insight will assist in the development of strategies for preventing K. pneumoniae infection.
[Mh] Termos MeSH primário: Proteína Receptora de AMP Cíclico/metabolismo
Proteínas de Fímbrias/metabolismo
Klebsiella pneumoniae/genética
Klebsiella pneumoniae/metabolismo
[Mh] Termos MeSH secundário: Aderência Bacteriana/fisiologia
Pegada de DNA
Desoxirribonuclease I/metabolismo
Ensaio de Desvio de Mobilidade Eletroforética
Escherichia coli
Regulação da Expressão Gênica/fisiologia
Testes de Hemaglutinação
Óperon Lac
Mananas/química
Fenótipo
Reação em Cadeia da Polimerase em Tempo Real
Saccharomyces cerevisiae
Deleção de Sequência
Transcrição Genética/fisiologia
beta-Galactosidase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cyclic AMP Receptor Protein); 0 (Mannans); 147680-16-8 (Fimbriae Proteins); EC 3.1.21.1 (Deoxyribonuclease I); EC 3.2.1.23 (beta-Galactosidase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170927
[Lr] Data última revisão:
170927
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170722
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0180666


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[PMID]:28716396
[Au] Autor:Darsouei R; Karimi J; Dunphy GB
[Ad] Endereço:Biocontrol and Insect Pathology Laboratory, Department of Plant Protection, School of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran.
[Ti] Título:The role of pilin protein of Xenorhabdus nematophila against immune defense reactions of insects.
[So] Source:J Insect Physiol;101:82-90, 2017 Aug.
[Is] ISSN:1879-1611
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Xenorhabdus nematophila is a symbiotic bacterium of the entomopathogenic nematode Steinernema carpocapsae (Weiser). It produces several toxic proteins which interfere with the immune system of insects. The current study shows that purified pilin protein could be a virulence trait of X. nematophila. The fifth instar larvae of Spodoptera exigua (Hübner) was injected with purified pilin. Changes in the cellular defenses in terms of total haemocyte counts and granulocyte percentage and humoral factors including total protease, phospholipase A , and phenoloxidase activities (humoral defense) as well as the expression of the three main antimicrobial peptides attacin, cecropin, and spodoptericin were measured at specific times. The level of THC and granulocytes in larvae with different concentrations of pilin protein were less than the negative control. Also agglutination of haemocytes was observed 8-16h post-injection. The pilin protein activated phenoloxidase in the initial hour post-injection, by 2hpi, activity was stable. The activities of phospholipase A2 and protease activities reached maximum levels at 12 and 4hpi, respectively, and then decreased. The expressions of attacin, cecropin, and spodoptericin in larvae treated with pilin protein were up-regulated above that of the normal sample. The overexpression of cecropin was greater than the other antimicrobial protein mRNA transcripts. The spodoptericin expression had an irregular trend while expressions of attacin and cecropin reached maximum levels at 4hpi and then decreased. Generally, after the injection of pilin protein, the cellular and humoral immune system of S. exigua is activated but this toxin was able to inhibit them. This is the first report of the role of pilin protein when the bacterial symbiont of S. carpocapsae encounters the humoral defense of an insect.
[Mh] Termos MeSH primário: Peptídeos Catiônicos Antimicrobianos/genética
Proteínas de Fímbrias/genética
Imunidade Inata
Spodoptera/imunologia
Spodoptera/microbiologia
Xenorhabdus/fisiologia
[Mh] Termos MeSH secundário: Animais
Peptídeos Catiônicos Antimicrobianos/metabolismo
Proteínas de Fímbrias/metabolismo
Larva/crescimento & desenvolvimento
Larva/imunologia
Larva/microbiologia
Análise de Sequência de DNA
Spodoptera/crescimento & desenvolvimento
Xenorhabdus/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antimicrobial Cationic Peptides); 147680-16-8 (Fimbriae Proteins)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170719
[St] Status:MEDLINE



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