Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
1.
J Aquat Anim Health ; 30(1): 50-56, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29595885

RESUMEN

Edwardsiella ictaluri is a facultative, intracellular, gram-negative bacterium that causes enteric septicemia of catfish (ESC). Edwardsiella ictaluri is known to be resistant to defense mechanisms present in catfish serum, which might aid in its use of a host's bloodstream to become septicemic. However, the precise mechanisms of the survival of E. ictaluri in host serum are not known. Analysis of the response of E. ictaluri to the host serum treatment at a proteomic level might aid in the elucidation of its adaptation mechanisms against defense mechanisms present in catfish serum. Thus, the objective of this study was to identify differentially regulated proteins of E. ictaluri upon exposure to naïve catfish serum. Two-dimensional difference gel electrophoresis (2D-DIGE) followed by in-gel trypsin digestion and MALDI-TOF/TOF analysis were used for identification of differentially expressed E. ictaluri proteins. A total of 19 differentially regulated proteins (7 up- and 12 downregulated) were identified. Among those were four putative immunogenic proteins, two chaperones and eight proteins involved in the translational process, two nucleic acid degradation and integration proteins, two intermediary metabolism proteins, and one iron-ion-binding protein. Further research focusing on the functions of these differentially expressed proteins may reveal their roles in host adaptation by E. ictaluri.


Asunto(s)
Proteínas Bacterianas/análisis , Bagres/sangre , Edwardsiella ictaluri/fisiología , Animales , Bagres/microbiología , Edwardsiella ictaluri/química , Edwardsiella ictaluri/metabolismo , Infecciones por Enterobacteriaceae , Enfermedades de los Peces/microbiología , Regulación Bacteriana de la Expresión Génica/fisiología , Interacciones Microbiota-Huesped , Proteómica
2.
PLoS One ; 10(7): e0132504, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26168192

RESUMEN

Edwardsiella ictaluri is a Gram-negative facultative anaerobe intracellular bacterium that causes enteric septicemia in channel catfish. Iron is an essential inorganic nutrient of bacteria and is crucial for bacterial invasion. Reduced availability of iron by the host may cause significant stress for bacterial pathogens and is considered a signal that leads to significant alteration in virulence gene expression. However, the precise effect of iron-restriction on E. ictaluri protein abundance is unknown. The purpose of this study was to identify differentially abundant proteins of E. ictaluri during in vitro iron-restricted conditions. We applied two-dimensional difference in gel electrophoresis (2D-DIGE) for determining differentially abundant proteins and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF/TOF MS) for protein identification. Gene ontology and pathway-based functional modeling of differentially abundant proteins was also conducted. A total of 50 unique differentially abundant proteins at a minimum of 2-fold (p ≤ 0.05) difference in abundance due to iron-restriction were detected. The numbers of up- and down-regulated proteins were 37 and 13, respectively. We noted several proteins, including EsrB, LamB, MalM, MalE, FdaA, and TonB-dependent heme/hemoglobin receptor family proteins responded to iron restriction in E. ictaluri.


Asunto(s)
Proteínas Bacterianas/análisis , Edwardsiella ictaluri/fisiología , Deficiencias de Hierro , Proteínas Bacterianas/aislamiento & purificación , Edwardsiella ictaluri/química , Edwardsiella ictaluri/metabolismo , Electroforesis en Gel Bidimensional , Regulación Bacteriana de la Expresión Génica/fisiología , Ontología de Genes , Técnicas In Vitro
3.
Microbiology (Reading) ; 158(Pt 2): 474-487, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22135098

RESUMEN

Bacteriophages ΦeiAU and ΦeiDWF are lytic to the catfish pathogen Edwardsiella (Edw.) ictaluri. The Edw. ictaluri host factors that modulate phage-host interactions have not been described previously. This study identified eleven unique Edw. ictaluri host factors essential for phage infection by screening a transposon mutagenized library of two Edw. ictaluri strains for phage-resistant mutants. Two mutants were isolated with independent insertions in the ompLC gene that encodes a putative outer membrane porin. Phage binding and efficiency of plaquing assays with Edw. ictaluri EILO, its ompLC mutant and a complemented mutant demonstrated that OmpLC serves as a receptor for phage ΦeiAU and ΦeiDWF adsorption. Comparison of translated OmpLCs from 15 Edw. ictaluri strains with varying degrees of phage susceptibility revealed that amino acid variations were clustered on the predicted extracellular loop 8 of OmpLC. Deletion of loop 8 of OmpLC completely abolished phage infectivity in Edw. ictaluri. Site-directed mutagenesis and transfer of modified ompLC genes to complement the ompLC mutants demonstrated that changes in ompLC sequences affect the degree of phage susceptibility. Furthermore, Edw. ictaluri strain Alg-08-183 was observed to be resistant to ΦeiAU, but phage progeny could be produced if phage DNA was electroporated into this strain. A host-range mutant of ΦeiAU, ΦeiAU-183, was isolated that was capable of infecting strain Alg-08-183 by using OmpLC as a receptor for adsorption. The results of this study identified Edw. ictaluri host factors required for phage infection and indicated that OmpLC is a principal molecular determinant of phage susceptibility in this pathogen.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/metabolismo , Bacteriófagos/fisiología , Bagres/microbiología , Edwardsiella ictaluri/metabolismo , Edwardsiella ictaluri/virología , Enfermedades de los Peces/microbiología , Especificidad del Huésped , Porinas/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/genética , Bacteriófagos/genética , Edwardsiella ictaluri/química , Edwardsiella ictaluri/genética , Datos de Secuencia Molecular , Porinas/química , Porinas/genética , Alineación de Secuencia
4.
Proteomics ; 9(5): 1353-63, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19253294

RESUMEN

Edwardsiella ictaluri is a facultative intracellular Gram-negative bacterium causing enteric septicemia of catfish (ESC), the most prevalent disease affecting farm-raised channel catfish in the United States. Despite its economic importance, studies addressing high-throughput proteomics were not possible because of lack of comprehensive protein database. Here, we report the first high-throughput proteomics analysis of E. ictaluri using 2-D LC ESI MS/MS and 2-DE MALDI TOF/TOF MS. Proteins identified in this study and predicted from the whole E. ictaluri genome were clustered into functional groups using clusters of orthologous groups (COG), and their subcellular locations were predicted. Possible functional relationships among proteins were determined using pathway analysis. The total number of unique E. ictaluri proteins identified using both 2-D LC and 2-DE approaches was 788, of which 15.48% (122) were identified by both methods while 78.43% (618) and 6.09% (48) were unique in 2-D LC and 2-DE, respectively. COG groupings and subcellular localizations were quite similar between our data set and proteins predicted from the whole genome. Twelve pathways were significantly represented in our dataset (p <0.05). Results from this study provided experimental evidence for many proteins that were predicted from the E. ictaluri genome annotation, and they should accelerate future functional and comparative studies aimed at understanding virulence mechanisms of this important pathogen.


Asunto(s)
Proteínas Bacterianas/análisis , Edwardsiella ictaluri/química , Proteoma/análisis , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Fenómenos Bioquímicos , Cromatografía Liquida , Edwardsiella ictaluri/citología , Edwardsiella ictaluri/genética , Edwardsiella ictaluri/patogenicidad , Electroforesis en Gel Bidimensional , Genoma , Proteoma/genética , Proteoma/aislamiento & purificación , Proteoma/metabolismo , Proteómica/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masas en Tándem
5.
Carbohydr Res ; 340(8): 1509-13, 2005 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-15882848

RESUMEN

The structural characterization of the antigenic O-polysaccharide component of the lipopolysaccharide produced by the fish pathogenic bacterium Edwardsiella ictaluri MT104 was undertaken by the application of NMR spectroscopy and chemical analysis. The O-chain was found to be a linear polymer of a repeating tetrasaccharide unit composed of D-glucose, 2-acetamido-2-deoxy-D-galactose, and D-galactose in a 1:2:1 ratio having the structure: [carbohydrate structure]; see text.


Asunto(s)
Edwardsiella ictaluri/química , Edwardsiella ictaluri/clasificación , Antígenos O/química , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular
6.
J Fish Dis ; 26(7): 415-21, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12946011

RESUMEN

The biological properties of Edwardsiella ictaluri RE-33 rifampicin-mutant and its parent strain EILO were analysed. RE-33 is an avirulent isolate used as a modified live vaccine against enteric septicaemia of catfish. Electrophoretic analysis of lipopolysaccharide (LPS) patterns showed high homology between both isolates. Further characterization of LPS by immunoblotting revealed the main differences in LPS composition. The RE-33 isolate lacks the high molecular weight bands of LPS (HMW-LPS). Outer membrane protein analysis also showed some immunological differences between RE-33 and the EILO parent strain. Only two fingerprinting techniques, fatty acid composition analysis and Biolog phenotypic profiles, were able to discriminate between both isolates.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/análisis , Edwardsiella ictaluri/genética , Edwardsiella ictaluri/fisiología , Ácidos Grasos/análisis , Genoma Bacteriano , Lipopolisacáridos/análisis , Rifampin/farmacología , Animales , Farmacorresistencia Bacteriana/genética , Edwardsiella ictaluri/química , Edwardsiella ictaluri/efectos de los fármacos , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Infecciones por Enterobacteriaceae/microbiología , Enfermedades de los Peces/tratamiento farmacológico , Enfermedades de los Peces/microbiología , Ictaluridae/microbiología , Mutación/genética , Fenotipo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA