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[PMID]:27773473
[Au] Autor:Levinson KJ; Baranova DE; Mantis NJ
[Ad] Endereço:Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY 12208, United States; Department of Biomedical Sciences, University at Albany, Albany, NY 12208, United States.
[Ti] Título:A monoclonal antibody that targets the conserved core/lipid A region of lipopolysaccharide affects motility and reduces intestinal colonization of both classical and El Tor Vibrio cholerae biotypes.
[So] Source:Vaccine;34(48):5833-5836, 2016 11 21.
[Is] ISSN:1873-2518
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Vibrio cholerae is the causative agent of cholera, an acute diarrheal disease that remains endemic in many parts of the world. The mechanisms underlying immunity to cholera remain poorly defined, though it is increasingly clear that protection is associated with antibodies against lipopolysaccharide (LPS). Here we report that ZAC-3, a monoclonal antibody against the core/lipid A region of V. cholerae LPS is a potent inhibitor of V. cholerae flagellum-based motility in viscous and liquid environments. ZAC-3 arrested motility of the classical Ogawa strain O395, as well as the El Tor Inaba strain C6706. In addition, we demonstrate, in the neonatal mouse model, that ZAC-3 IgG and Fab fragments significantly reduced the ability of both V. cholerae strains O395 and C6706 to colonize the intestinal epithelium, revealing the potential of antibodies against the core/lipid A to contribute to immunity across biotypes, possibly through a mechanism involving motility arrest.
[Mh] Termos MeSH primário: Anticorpos Monoclonais/imunologia
Cólera/microbiologia
Cólera/prevenção & controle
Lipídeo A/imunologia
Vibrio cholerae/imunologia
[Mh] Termos MeSH secundário: Animais
Animais Recém-Nascidos
Anticorpos Antibacterianos/imunologia
Anticorpos Monoclonais/administração & dosagem
Antígenos de Bactérias/imunologia
Técnicas de Tipagem Bacteriana
Modelos Animais de Doenças
Flagelos/efeitos dos fármacos
Flagelos/fisiologia
Fragmentos Fab das Imunoglobulinas/administração & dosagem
Fragmentos Fab das Imunoglobulinas/imunologia
Imunoglobulina G/administração & dosagem
Imunoglobulina G/imunologia
Mucosa Intestinal/imunologia
Mucosa Intestinal/microbiologia
Lipídeo A/química
Camundongos
Movimento
Vibrio cholerae/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Antibodies, Bacterial); 0 (Antibodies, Monoclonal); 0 (Antigens, Bacterial); 0 (Immunoglobulin Fab Fragments); 0 (Immunoglobulin G); 0 (Lipid A)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:180206
[Lr] Data última revisão:
180206
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161025
[St] Status:MEDLINE


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[PMID]:29239606
[Au] Autor:Fan L; Xie P; Wang Y; Huang Z; Zhou J
[Ad] Endereço:Institute of Agro-product Processing , Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China.
[Ti] Título:Biosurfactant-Protein Interaction: Influences of Mannosylerythritol Lipids-A on ß-Glucosidase.
[So] Source:J Agric Food Chem;66(1):238-246, 2018 Jan 10.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this work, the influences of a biosurfactant, mannosylerythritol lipids-A (MEL-A) toward ß-glucosidase activity and their molecular interactions were studied by using differential scanning calorimetry (DSC), circular dichroism spectroscopy (CD), isothermal titration calorimetry (ITC), and docking simulation. The enzyme inhibition kinetics data showed that MEL-A at a low concentration (< critical micelle concentration (CMC), 20.0 ± 5.0 µM) enhanced ß-glucosidase activity, whereas it inhibited the enzyme activity at higher concentrations more than 20.0 µM, followed by a decreased V and K of ß-glucosidase. The thermodynamics and structural data demonstrated that the midpoint temperature (T ) and unfolding enthalpy (ΔH) of ß-glucosidase was shifted to high values (76.6 °C, 126.3 J/g) in the presence of MEL-A, and the secondary structure changes of ß-glucosidase, including the increased α-helix, ß-turn, or random coil contents, and a decreased ß-sheet content were caused by MEL-A at a CMC concentration. The further ITC and docking simulations suggested the bindings of MEL-A toward ß-glucosidase were driven by weak hydrophobic interactions happened between the amino acid residues of ß-glucosidase and the fatty acid residues of MEL-A, in addition to hydrogen bonds between amino acids and hydroxyl in glycosyl residues of this biosurfactant.
[Mh] Termos MeSH primário: Glicolipídeos/química
Lipídeo A/química
Tensoativos/química
beta-Glucosidase/química
[Mh] Termos MeSH secundário: Interações Hidrofóbicas e Hidrofílicas
Cinética
Ligação Proteica
Estrutura Secundária de Proteína
Temperatura Ambiente
Termodinâmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Glycolipids); 0 (Lipid A); 0 (Surface-Active Agents); 0 (mannosylerythritol lipid); EC 3.2.1.21 (beta-Glucosidase)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180205
[Lr] Data última revisão:
180205
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171215
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b04469


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[PMID]:28464026
[Au] Autor:Diemert DJ; Freire J; Valente V; Fraga CG; Talles F; Grahek S; Campbell D; Jariwala A; Periago MV; Enk M; Gazzinelli MF; Bottazzi ME; Hamilton R; Brelsford J; Yakovleva A; Li G; Peng J; Correa-Oliveira R; Hotez P; Bethony J
[Ad] Endereço:Department of Microbiology, Immunology and Tropical Medicine, School of Medicine and Health Sciences, The George Washington University, Washington DC, United States of America.
[Ti] Título:Safety and immunogenicity of the Na-GST-1 hookworm vaccine in Brazilian and American adults.
[So] Source:PLoS Negl Trop Dis;11(5):e0005574, 2017 05.
[Is] ISSN:1935-2735
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Necator americanus Glutathione-S-Transferase-1 (Na-GST-1) plays a role in the digestion of host hemoglobin by adult N. americanus hookworms. Vaccination of laboratory animals with recombinant Na-GST-1 is associated with significant protection from challenge infection. Recombinant Na-GST-1 was expressed in Pichia pastoris and adsorbed to aluminum hydroxide adjuvant (Alhydrogel) according to current Good Manufacturing Practice. Two Phase 1 trials were conducted in 142 healthy adult volunteers in the United States and Brazil, first in hookworm-naïve individuals and then in residents of a N. americanus endemic area in Brazil. Volunteers received one of three doses of recombinant Na-GST-1 (10, 30, or 100 µg) adjuvanted with Alhydrogel, adjuvanted with Alhydrogel and co-administered with an aqueous formulation of Glucopyranosyl Lipid A (GLA-AF), or the hepatitis B vaccine. Vaccinations were administered via intramuscular injection on days 0, 56, and 112. Na-GST-1/Alhydrogel was well tolerated in both hookworm-naïve and hookworm-exposed adults, with the most common adverse events being mild to moderate injection site pain and tenderness, and mild headache and nausea; no vaccine-related severe or serious adverse events were observed. Antigen-specific IgG antibodies were induced in a dose-dependent fashion, with increasing levels observed after each vaccination in both trials. The addition of GLA-AF to Na-GST-1/Alhydrogel did not result in significant increases in specific IgG responses. In both the US and Brazil studies, the predominant IgG subclass induced against Na-GST-1 was IgG1, with lesser amounts of IgG3. Vaccination of both hookworm-naïve and hookworm-exposed adults with recombinant Na-GST-1 was safe, well tolerated, and resulted in significant antigen-specific IgG responses. Based on these results, this vaccine will be advanced into clinical trials in children and eventual efficacy studies. TRIAL REGISTRATION: ClinicalTrials.gov (NCT01261130 for the Brazil trial and NCT01385189 for the US trial).
[Mh] Termos MeSH primário: Ancylostomatoidea/imunologia
Antígenos de Helmintos/imunologia
Glutationa Transferase/imunologia
Infecções por Uncinaria/prevenção & controle
Vacinas Sintéticas/imunologia
[Mh] Termos MeSH secundário: Adjuvantes Imunológicos/administração & dosagem
Adolescente
Adulto
Hidróxido de Alumínio/administração & dosagem
Animais
Anticorpos Anti-Helmínticos/sangue
Brasil
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia
Feminino
Glucosídeos/administração & dosagem
Voluntários Saudáveis
Vacinas contra Hepatite B/administração & dosagem
Infecções por Uncinaria/imunologia
Seres Humanos
Imunoglobulina G/sangue
Injeções Intramusculares
Lipídeo A/administração & dosagem
Masculino
Meia-Idade
Resultado do Tratamento
Estados Unidos
Vacinas Sintéticas/administração & dosagem
Vacinas Sintéticas/efeitos adversos
Adulto Jovem
[Pt] Tipo de publicação:CLINICAL TRIAL, PHASE I; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Adjuvants, Immunologic); 0 (Antibodies, Helminth); 0 (Antigens, Helminth); 0 (Glucosides); 0 (Hepatitis B Vaccines); 0 (Immunoglobulin G); 0 (Lipid A); 0 (Vaccines, Synthetic); 0 (glucopyranosyl lipid-A); 5QB0T2IUN0 (Aluminum Hydroxide); EC 2.5.1.18 (Glutathione Transferase)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:180129
[Lr] Data última revisão:
180129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[Cl] Clinical Trial:ClinicalTrial
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pntd.0005574


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[PMID]:29020117
[Au] Autor:Matson JS; Livny J; DiRita VJ
[Ad] Endereço:Department of Medical Microbiology and Immunology, University of Toledo Medical School, Toledo, Ohio, United States of America.
[Ti] Título:A putative Vibrio cholerae two-component system controls a conserved periplasmic protein in response to the antimicrobial peptide polymyxin B.
[So] Source:PLoS One;12(10):e0186199, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The epidemic pathogen Vibrio cholerae senses and responds to different external stresses it encounters in the aquatic environment and in the human host. One stress that V. cholerae encounters in the host is exposure to antimicrobial peptides on mucosal surfaces. We used massively parallel cDNA sequencing (RNA-Seq) to quantitatively identify the transcriptome of V. cholerae grown in the presence and absence of sub-lethal concentrations of the antimicrobial peptide polymyxin B. We evaluated the transcriptome of both wild type V. cholerae and a mutant carrying a deletion of vc1639, a putative sensor kinase of an uncharacterized two-component system, under these conditions. In addition to many previously uncharacterized pathways responding with elevated transcript levels to polymyxin B exposure, we confirmed the predicted elevated transcript levels of a previously described LPS modification system in response to polymyxin B exposure. Additionally, we identified the V. cholerae homologue of visP (ygiW) as a regulatory target of VC1639. VisP is a conserved periplasmic protein implicated in lipid A modification in Salmonellae. This study provides the first systematic analysis of the transcriptional response of Vibrio cholerae to polymyxin B, raising important questions for further study regarding mechanisms used by V. cholerae to sense and respond to envelope stress.
[Mh] Termos MeSH primário: Peptídeos Catiônicos Antimicrobianos/farmacologia
Proteínas de Bactérias/metabolismo
Sequência Conservada
Proteínas Periplásmicas/metabolismo
Polimixina B/farmacologia
Transdução de Sinais
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Perfilação da Expressão Gênica
Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos
Lipídeo A/metabolismo
Proteínas Periplásmicas/genética
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
Análise de Sequência de RNA
Transdução de Sinais/efeitos dos fármacos
Transdução de Sinais/genética
Vibrio cholerae/efeitos dos fármacos
Vibrio cholerae/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antimicrobial Cationic Peptides); 0 (Bacterial Proteins); 0 (Lipid A); 0 (Periplasmic Proteins); 0 (RNA, Messenger); 1404-26-8 (Polymyxin B)
[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:171012
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0186199


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[PMID]:28987239
[Au] Autor:Hong SK; Choo EH; Ihm SH; Chang K; Seung KB
[Ad] Endereço:Division of Cardiology, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
[Ti] Título:Dipeptidyl peptidase 4 inhibitor attenuates obesity-induced myocardial fibrosis by inhibiting transforming growth factor-ßl and Smad2/3 pathways in high-fat diet-induced obesity rat model.
[So] Source:Metabolism;76:42-55, 2017 Nov.
[Is] ISSN:1532-8600
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Obesity-induced myocardial fibrosis may lead to diastolic dysfunction and ultimately heart failure. Activation of the transforming growth factor (TGF)-ßl and its downstream Smad2/3 pathways may play a pivotal role in the pathogenesis of obesity-induced myocardial fibrosis, and the antidiabetic dipeptidyl peptidase 4 inhibitors (DPP4i) might affect these pathways. We investigated whether DPP4i reduces myocardial fibrosis by inhibiting the TGF-ß1 and Smad2/3 pathways in the myocardium of a diet-induced obesity (DIO) rat model. Eight-week-old male spontaneously hypertensive rats (SHRs) were fed either a normal fat diet (chow) or a high-fat diet (HFD) and then the HFD-fed SHRs were randomized to either the DPP4i (MK-0626) or control (distilled water) groups for 12weeks. At 20weeks old, all the rats underwent hemodynamic and metabolic studies and Doppler echocardiography. Compared with the normal fat diet (chow)-fed SHRs, the HFD-fed SHRs developed a more intense degree of hyperglycemia and dyslipidemia and showed a constellation of left ventricular (LV) diastolic dysfunction, and exacerbated myocardial fibrosis, as well as activation of the TGF-ß1 and Smad2/3 pathways. DPP4i significantly improved the metabolic and hemodynamic parameters. The echocardiogram showed that DPP4i improved the LV diastolic dysfunction (early to late ventricular filling velocity [E/A] ratio, 1.49±0.21 vs. 1.77±0.09, p<0.05). Furthermore, DPP4i significantly reduced myocardial fibrosis and collagen production by the myocardium and suppressed TGF-ß1 and phosphorylation of Smad2/3 in the heart. In addition, DPP4i decreased TGF-ß1-induced collagen production and TGF-ß1-mediated phosphorylation and nuclear translocation of Smad2/3 in rat cardiac fibroblasts. In conclusion, DPP4 inhibition attenuated myocardial fibrosis and improved LV diastolic dysfunction in a DIO rat model by modulating the TGF-ß1 and Smad2/3 pathways.
[Mh] Termos MeSH primário: Inibidores da Dipeptidil Peptidase IV/farmacologia
Miocárdio/patologia
Obesidade/metabolismo
Transdução de Sinais/efeitos dos fármacos
Proteína Smad2/metabolismo
Proteína Smad3/metabolismo
Fator de Crescimento Transformador beta1/metabolismo
Triazóis/farmacologia
[Mh] Termos MeSH secundário: Animais
Glicemia
Dieta Hiperlipídica
Inibidores da Dipeptidil Peptidase IV/uso terapêutico
Fibrose/tratamento farmacológico
Fibrose/etiologia
Fibrose/metabolismo
Fibrose/patologia
Insulina/sangue
Lipídeo A/sangue
Masculino
Miocárdio/metabolismo
Obesidade/complicações
Obesidade/patologia
Ratos
Ratos Endogâmicos SHR
Triazóis/uso terapêutico
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Blood Glucose); 0 (Dipeptidyl-Peptidase IV Inhibitors); 0 (Insulin); 0 (Lipid A); 0 (MK0626); 0 (Smad2 Protein); 0 (Smad3 Protein); 0 (Transforming Growth Factor beta1); 0 (Triazoles)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171009
[St] Status:MEDLINE


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[PMID]:28963929
[Au] Autor:Rostamian M; Niknam HM
[Ad] Endereço:Immunology Department, Pasteur Institute of Iran, Tehran, 13164, Iran.
[Ti] Título:Evaluation of the adjuvant effect of agonists of toll-like receptor 4 and 7/8 in a vaccine against leishmaniasis in BALB/c mice.
[So] Source:Mol Immunol;91:202-208, 2017 11.
[Is] ISSN:1872-9142
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:There is no effective vaccine against human leishmaniasis. Achieving successful vaccines seems to need powerful adjuvants. Separate or combined use of toll like receptor (TLR) agonists as adjuvant is a promising approach in Leishmania vaccine research. In present study, we evaluated adjuvant effect of separate or combined use of a TLR7/8 agonist, R848 and a TLR4 agonist, monophosphoryl lipid A (MPL) beside soluble Leishmania antigen (SLA) in BALB/c mice. Mice were vaccinated three times by SLA with separate or combined TLR7/8 and TLR4 agonists and were then challenged by Leishmania major. Delay type hypersensitivity, lesion development, parasite load, and cytokines (interferon gamma, and interleukin-10) response were assessed. Results showed: 1) MPL can slightly assist SLA in parasite load reduction, but it is not able to increase SLA ability in evoking DTH and cytokine responses or decreasing lesion diameter. 2) R848 does not affect the DTH response and parasite load of mice vaccinated with SLA, but it decreases/inhibits cytokine responses induced by SLA, leading to increase lesion diameter. 3) MPL neutralized inhibitory effect of R848. In overall, these data emphasize that MPL slightly assists SLA to make a more potent vaccine, but R848 is not a good adjuvant to induce T cell-dependent immune response in BALB/c mice, and therefore combination of these TLR agonists in the current formulation, is not recommended for making a more powerful adjuvant.
[Mh] Termos MeSH primário: Adjuvantes Imunológicos/farmacologia
Imidazóis/farmacologia
Leishmania major/imunologia
Vacinas contra Leishmaniose/farmacologia
Leishmaniose Cutânea/prevenção & controle
Lipídeo A/análogos & derivados
Glicoproteínas de Membrana/agonistas
Receptor 4 Toll-Like/agonistas
Receptor 7 Toll-Like/agonistas
Receptor 8 Toll-Like/agonistas
[Mh] Termos MeSH secundário: Animais
Antígenos de Protozoários/imunologia
Antígenos de Protozoários/farmacologia
Hipersensibilidade Tardia/imunologia
Hipersensibilidade Tardia/patologia
Imidazóis/imunologia
Interferon gama/imunologia
Interleucina-10/imunologia
Vacinas contra Leishmaniose/imunologia
Leishmaniose Cutânea/imunologia
Leishmaniose Cutânea/patologia
Lipídeo A/imunologia
Lipídeo A/farmacologia
Glicoproteínas de Membrana/imunologia
Camundongos
Camundongos Endogâmicos BALB C
Receptor 4 Toll-Like/imunologia
Receptor 7 Toll-Like/imunologia
Receptor 8 Toll-Like/imunologia
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Adjuvants, Immunologic); 0 (Antigens, Protozoan); 0 (IFNG protein, mouse); 0 (IL10 protein, mouse); 0 (Imidazoles); 0 (Leishmaniasis Vaccines); 0 (Lipid A); 0 (Membrane Glycoproteins); 0 (TLR8 protein, mouse); 0 (Tlr4 protein, mouse); 0 (Tlr7 protein, mouse); 0 (Toll-Like Receptor 4); 0 (Toll-Like Receptor 7); 0 (Toll-Like Receptor 8); 130068-27-8 (Interleukin-10); 82115-62-6 (Interferon-gamma); MWC0ET1L2P (monophosphoryl lipid A); V3DMU7PVXF (resiquimod)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171120
[Lr] Data última revisão:
171120
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171001
[St] Status:MEDLINE


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[PMID]:28874446
[Au] Autor:Harper M; Wright A; St Michael F; Li J; Deveson Lucas D; Ford M; Adler B; Cox AD; Boyce JD
[Ad] Endereço:Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash University, VIC, Australia marina.harper@monash.edu.
[Ti] Título:Characterization of Two Novel Lipopolysaccharide Phosphoethanolamine Transferases in Pasteurella multocida and Their Role in Resistance to Cathelicidin-2.
[So] Source:Infect Immun;85(11), 2017 Nov.
[Is] ISSN:1098-5522
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The lipopolysaccharide (LPS) produced by the Gram-negative bacterial pathogen has phosphoethanolamine (PEtn) residues attached to lipid A, 3-deoxy-d-manno-octulosonic acid (Kdo), heptose, and galactose. In this report, we show that PEtn is transferred to lipid A by the EptA homologue, PetL, and is transferred to galactose by a novel PEtn transferase that is unique to called PetG. Transcriptomic analyses indicated that expression was positively regulated by the global regulator Fis and negatively regulated by an Hfq-dependent small RNA. Importantly, we have identified a novel PEtn transferase called PetK that is responsible for PEtn addition to the single Kdo molecule (Kdo ), directly linked to lipid A in the glycoform A LPS. assays showed that the presence of a functional and , and therefore the presence of PEtn on lipid A and Kdo , was essential for resistance to the cationic, antimicrobial peptide cathelicidin-2. The importance of PEtn on Kdo and the identification of the transferase responsible for this addition have not previously been shown. Phylogenetic analysis revealed that PetK is the first representative of a new family of predicted PEtn transferases. The PetK family consists of uncharacterized proteins from a range of Gram-negative bacteria that produce LPS glycoforms with only one Kdo molecule, including pathogenic species within the genera , , and We predict that many of these bacteria will require the addition of PEtn to Kdo for maximum protection against host antimicrobial peptides.
[Mh] Termos MeSH primário: Proteínas de Bactérias/genética
Proteínas Sanguíneas/toxicidade
Farmacorresistência Bacteriana/genética
Etanolaminofosfotransferase/genética
Regulação Bacteriana da Expressão Gênica
Pasteurella multocida/genética
Pasteurella multocida/patogenicidade
Precursores de Proteínas/toxicidade
[Mh] Termos MeSH secundário: Animais
Proteínas de Bactérias/metabolismo
Galinhas
Biologia Computacional
Etanolaminofosfotransferase/metabolismo
Etanolaminas/química
Etanolaminas/metabolismo
Fator Proteico para Inversão de Estimulação/genética
Fator Proteico para Inversão de Estimulação/metabolismo
Galactose/química
Galactose/metabolismo
Perfilação da Expressão Gênica
Heptoses/química
Heptoses/metabolismo
Isoenzimas
Lipídeo A/química
Lipídeo A/metabolismo
Mutação
Proteínas Nucleares/genética
Proteínas Nucleares/metabolismo
Infecções por Pasteurella/microbiologia
Infecções por Pasteurella/patologia
Pasteurella multocida/classificação
Pasteurella multocida/efeitos dos fármacos
Filogenia
Açúcares Ácidos/química
Açúcares Ácidos/metabolismo
Transcriptoma
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Blood Proteins); 0 (Ethanolamines); 0 (Factor For Inversion Stimulation Protein); 0 (Heptoses); 0 (Isoenzymes); 0 (Lipid A); 0 (Nuclear Proteins); 0 (Protein Precursors); 0 (Sugar Acids); 0 (cathelicidin 2 protein, mammal); 1069-03-0 (2-keto-3-deoxyoctonate); 78A2BX7AEU (phosphorylethanolamine); EC 2.7.8.1 (Ethanolaminephosphotransferase); X2RN3Q8DNE (Galactose)
[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:170907
[St] Status:MEDLINE


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[PMID]:28719181
[Au] Autor:Rynkiewicz MJ; Wu H; Cafarella TR; Nikolaidis NM; Head JF; Seaton BA; McCormack FX
[Ad] Endereço:Department of Physiology and Biophysics, Boston University School of Medicine , Boston, Massachusetts 02118, United States.
[Ti] Título:Differential Ligand Binding Specificities of the Pulmonary Collectins Are Determined by the Conformational Freedom of a Surface Loop.
[So] Source:Biochemistry;56(31):4095-4105, 2017 Aug 08.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Lung surfactant proteins (SPs) play critical roles in surfactant function and innate immunity. SP-A and SP-D, members of the collectin family of C-type lectins, exhibit distinct ligand specificities, effects on surfactant structure, and host defense functions despite extensive structural homology. SP-A binds to dipalmitoylphosphatidylcholine (DPPC), the major surfactant lipid component, but not phosphatidylinositol (PI), whereas SP-D shows the opposite preference. Additionally, SP-A and SP-D recognize widely divergent pathogen-associated molecular patterns. Previous studies suggested that a ligand-induced surface loop conformational change unique to SP-A contributes to lipid binding affinity. To test this hypothesis and define the structural features of SP-A and SP-D that determine their ligand binding specificities, a structure-guided approach was used to introduce key features of SP-D into SP-A. A quadruple mutant (E171D/P175E/R197N/K203D) that introduced an SP-D-like loop-stabilizing calcium binding site into the carbohydrate recognition domain was found to interconvert SP-A ligand binding preferences to an SP-D phenotype, exchanging DPPC for PI specificity, and resulting in the loss of lipid A binding and the acquisition of more avid mannan binding properties. Mutants with constituent single or triple mutations showed alterations in their lipid and sugar binding properties that were intermediate between those of SP-A and SP-D. Structures of mutant complexes with inositol or methyl-mannose revealed an attenuation of the ligand-induced conformational change relative to wild-type SP-A. These studies suggest that flexibility in a key surface loop supports the distinctive lipid binding functions of SP-A, thus contributing to its multiple functions in surfactant structure and regulation, and host defense.
[Mh] Termos MeSH primário: Modelos Moleculares
Proteína A Associada a Surfactante Pulmonar/metabolismo
Proteína D Associada a Surfactante Pulmonar/metabolismo
[Mh] Termos MeSH secundário: 1,2-Dipalmitoilfosfatidilcolina/química
1,2-Dipalmitoilfosfatidilcolina/metabolismo
Substituição de Aminoácidos
Animais
Sítios de Ligação
Cristalografia por Raios X
Cinética
Lectinas Tipo C/química
Lectinas Tipo C/metabolismo
Ligantes
Lipídeo A/química
Lipídeo A/metabolismo
Lipossomos
Mutagênese Sítio-Dirigida
Mutação
Fosfatidilinositóis/química
Fosfatidilinositóis/metabolismo
Conformação Proteica
Domínios e Motivos de Interação entre Proteínas
Redobramento de Proteína
Estabilidade Proteica
Proteína A Associada a Surfactante Pulmonar/química
Proteína A Associada a Surfactante Pulmonar/genética
Proteína D Associada a Surfactante Pulmonar/química
Proteína D Associada a Surfactante Pulmonar/genética
Ratos
Proteínas Recombinantes de Fusão/química
Proteínas Recombinantes de Fusão/metabolismo
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lectins, C-Type); 0 (Ligands); 0 (Lipid A); 0 (Liposomes); 0 (Phosphatidylinositols); 0 (Pulmonary Surfactant-Associated Protein A); 0 (Pulmonary Surfactant-Associated Protein D); 0 (Recombinant Fusion Proteins); 2644-64-6 (1,2-Dipalmitoylphosphatidylcholine)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170719
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.6b01313


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[PMID]:28652313
[Au] Autor:Mills G; Dumigan A; Kidd T; Hobley L; Bengoechea JA
[Ad] Endereço:Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, United Kingdom.
[Ti] Título:Identification and Characterization of Two Klebsiella pneumoniae Lipid A Late Acyltransferases and Their Role in Virulence.
[So] Source:Infect Immun;85(9), 2017 Sep.
[Is] ISSN:1098-5522
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:causes a wide range of infections, from urinary tract infections to pneumonia. The lipopolysaccharide is a virulence factor of this pathogen, although there are gaps in our understanding of its biosynthesis. Here we report on the characterization of , which encodes one of the enzymes responsible for the late secondary acylation of immature lipid A molecules. Analysis of the available genomes revealed that this pathogen's genome encodes two orthologues of LpxL. Using genetic methods and mass spectrometry, we demonstrate that LpxL1 catalyzes the addition of laureate and LpxL2 catalyzes the addition of myristate. Both enzymes acylated lipid A, whereas only LpxL2 mediated lipid A acylation. We show that LpxL1 is negatively regulated by the two-component system PhoPQ. The lipid A produced by the mutant lacked the 2-hydroxymyristate, palmitate, and 4-aminoarabinose decorations found in the lipid A synthesized by the wild type. The lack of 2-hydroxymyristate was expected since LpxO modifies the myristate transferred by LpxL2 to the lipid A. The absence of the other two decorations is most likely caused by the downregulation of and expression. LpxL2-dependent lipid A acylation protects from polymyxins, mediates resistance to phagocytosis, limits the activation of inflammatory responses by macrophages, and is required for pathogen survival in the wax moth ( ). Our findings indicate that the LpxL2 contribution to virulence is dependent on LpxO-mediated hydroxylation of the LpxL2-transferred myristate. Our studies suggest that LpxL2 might be a candidate target in the development of anti- drugs.
[Mh] Termos MeSH primário: Aciltransferases/genética
Aciltransferases/metabolismo
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Klebsiella pneumoniae/enzimologia
Lipídeo A/metabolismo
Fatores de Virulência/genética
Fatores de Virulência/metabolismo
[Mh] Termos MeSH secundário: Animais
Células Cultivadas
Modelos Animais de Doenças
Deleção de Genes
Regulação Bacteriana da Expressão Gênica
Infecções por Klebsiella/microbiologia
Klebsiella pneumoniae/genética
Klebsiella pneumoniae/patogenicidade
Lepidópteros
Macrófagos/microbiologia
Espectrometria de Massas
Camundongos
Fagocitose
Virulência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Lipid A); 0 (Virulence Factors); EC 2.3.- (Acyltransferases); EC 2.3.- (LpxL protein, bacteria)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170906
[Lr] Data última revisão:
170906
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170628
[St] Status:MEDLINE


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[PMID]:28650563
[Au] Autor:Casillo A; Ziaco M; Lindner B; Parrilli E; Schwudke D; Holgado A; Verstrepen L; Sannino F; Beyaert R; Lanzetta R; Tutino ML; Corsaro MM
[Ad] Endereço:Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126, Naples, Italy.
[Ti] Título:Unusual Lipid A from a Cold-Adapted Bacterium: Detailed Structural Characterization.
[So] Source:Chembiochem;18(18):1845-1854, 2017 Sep 19.
[Is] ISSN:1439-7633
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Colwellia psychrerythraea 34H is a Gram-negative cold-adapted microorganism that adopts many strategies to cope with the limitations associated with the low temperatures of its habitat. In this study, we report the complete characterization of the lipid A moiety from the lipopolysaccharide of Colwellia. Lipid A and its partially deacylated derivative were completely characterized by high-resolution mass spectrometry, NMR spectroscopy, and chemical analysis. An unusual structure with a 3-hydroxy unsaturated tetradecenoic acid as a component of the primary acylation pattern was identified. In addition, the presence of a partially acylated phosphoglycerol moiety on the secondary acylation site at the 3-position of the reducing 2-amino-2-deoxyglucopyranose unit caused tremendous natural heterogeneity in the structure of lipid A. Biological-activity assays indicated that C. psychrerythraea 34H lipid A did not show an agonistic or antagonistic effect upon testing in human macrophages.
[Mh] Termos MeSH primário: Alteromonadaceae/metabolismo
Lipídeo A/química
[Mh] Termos MeSH secundário: Temperatura Baixa
Cromatografia Gasosa-Espectrometria de Massas
Lipídeo A/metabolismo
Espectroscopia de Ressonância Magnética
Espectrometria de Massas por Ionização por Electrospray
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lipid A)
[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:170627
[St] Status:MEDLINE
[do] DOI:10.1002/cbic.201700287



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