title: Identification of Differentially Abundant Proteins of Edwardsiella ictaluri during Iron Restriction.
abstract: 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.
authors.affiliation: The Rogosin Institute, Xenia Division, Xenia, Ohio, United States of America.
authors.forename: Pradeep R
authors.initials: PR
authors.lastname: Dumpala
authors.affiliation: USDA ARS Warmwater Aquaculture Research Unit, Thad Cochran National Warmwater Aquaculture Center, Stoneville, Mississippi, United States of America.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Peterson
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, United States of America.
authors.forename: Mark L
authors.initials: ML
authors.lastname: Lawrence
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, United States of America.
authors.forename: Attila
authors.initials: A
authors.lastname: Karsi
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis* / Q000302:isolation & purification; D020610:Edwardsiella ictaluri / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D015180:Electrophoresis, Gel, Two-Dimensional; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D063990:Gene Ontology; D066298:In Vitro Techniques; D000090463:Iron Deficiencies
chemical_list: D001426:Bacterial Proteins