effect of temperature on the immune system of channel catfish (ictalurus punctatus)--ii. adaptation of anterior kidney phagocytes to 10 degrees c.1. anterior kidney phagocytes from channel catfish (ictalurus punctatus) exposed to 10 and 24 degrees c from 1 day to 5 weeks were assayed for phagocytic ability and respiratory burst activity to aeromonas hydrophila and edwardsiella ictaluri. 2. the results of this study indicated that phagocytosis in channel catfish remained partially functional at low temperature without adaptation, although partial suppression was observed. 3. adaptation to low temperature did lead to an improvement in the r ...19911685385
outer membrane protein profiles of edwardsiella ictaluri from fish.outer membrane proteins (omp) prepared with sodium n-lauroyl sarcocinate (sls) from 33 edwardsiella ictaluri isolates from fish were examined by electrophoresis. twenty-eight isolates from channel catfish (ictalurus punctatus) had similar omp profiles. ten bands (71 kilodaltons [kd] to 19.5 kd) were identified in all isolates from channel catfish. one major 35-kd protein comprised most of the protein content of the outer membrane of isolates from channel catfish. differences existed among isolat ...19901689127
serological investigation of the fish pathogen edwardsiella ictaluri, cause of enteric septicemia of catfish.the serological relationships among 32 isolates of edwardsiella ictaluri obtained from fish were studied. the strains were extremely homogeneous in protein and lipopolysaccharide preparations as observed by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis. only minor variations were observed in the structural o-side chain subunits in three isolates; however, such variation did not preclude antigenic recognition by two e. ictaluri antisera in either microagglutination or western blot imm ...19901692595
pathogenic properties of edwardsiella species.the pathogenic characteristics of 35 edwardsiella strains from clinical and environmental sources were investigated. overall, most edwardsiella tarda strains were invasive in hep-2 cell monolayers, produced a cell-associated hemolysin and siderophores, and bound congo red; many strains also expressed mannose-resistant hemagglutination against guinea pig erythrocytes. edwardsiella hoshinae strains bound congo red and were variable in their invasive and hemolytic capabilities while edwardsiella ic ...19911774326
penetration and replication of edwardsiella spp. in hep-2 cells.the ability of 22 edwardsiella strains to penetrate and replicate in cultured epithelial cells was initially evaluated by light microscopy methods and by the recovery of gentamicin-resistant (gmr) bacteria from the triton x-100 cell lysates of hep-2-infected monolayers. giemsa-stained hep-2 cells revealed the presence of numerous internalized bacteria 3 h postinfection, often appearing as parallel rows of replicated bacteria within the cytosol and sometimes obliterating the cytoplasm because of ...19911987028
fish mortality in the mississippi catfish farming industry in 1988: causes and treatments.the 1988 fish mortality summary for the catfish (ictalurus punctatus) industry in mississippi is presented. in 1988, 2,456 cases were submitted to mississippi cooperative extension service fish disease laboratories at belzoni and stoneville. bacterial infection caused by edwardsiella ictaluri was the leading cause of catfish mortality. descriptions and treatments are presented for bacterial, parasitic, viral and other diseases affecting mississippi farm-raised catfish in 1988.19912023314
in vitro responses of channel catfish, ictalurus punctatus, neutrophils to edwardsiella ictaluri.the in vitro responses of channel catfish peripheral blood neutrophils to edwardsiella ictaluri were examined through the use of phagocytic, bactericidal, and chemiluminescent assays. evidence from both light and electron microscopy indicate that catfish neutrophils appeared to phagocytose e. ictaluri. although extracellular killing of e. ictaluri was observed, bactericidal assays did not demonstrate intracellular killing of e. ictaluri by neutrophils. catfish neutrophils mount a chemiluminescen ...19912050246
a medium for the selective isolation of edwardsiella ictaluri.a selective medium, called edwardsiella ictaluri medium (eim), has been formulated for the isolation of edwardsiella ictaluri. the medium inhibits the growth of most gram-negative bacteria, except proteus sp., serratia marcescens and some isolates of aeromonas hydrophila and yersinia ruckeri. the bacteria that grow on the eim are easily differentiated from e. ictaluri based on colony morphology. the eim inhibits gram-positive bacteria with the exception of enterococci. the addition of fungizone ...19902338726
differences in the phagocytosis of four bacteria by channel catfish neutrophils.the purpose of this study was to compare the phagocytosis of aeromonas hydrophila, edwardsiella ictaluri, edwardsiella tarda and micrococcus luteus by channel catfish neutrophils. various aspects of opsonization effect and bactericidal ability of channel catfish neutrophils were investigated. percent phagocytosis ranged from a low of 1% to a high of 91%. the highest percent phagocytosis and phagocytic indices routinely occurred with normal serum and were highest for m. luteus (91.78%, 55.25) and ...19902369968
plasmid homologies in edwardsiella ictaluri.plasmids from all available non-channel catfish isolates of edwardsiella ictaluri were classified by gel electrophoresis and hybridization methods. all isolates, regardless of source, contained classes of homologous plasmids with similar but not identical sizes.19892619312
automated biochemical identification of bacterial fish pathogens using the abbott quantum ii.the quantum ii, originally designed by abbott diagnostics for automated rapid identification of members of enterobacteriaceae, was adapted for the identification of bacterial fish pathogens. the instrument operates as a spectrophotometer at a wavelength of 492.600 nm. a sample cartridge containing 20 inoculated biochemical chambers is inserted in the path of the analyzing beam. reactions are converted into a 7-digit octal biocode, relayed via a sensor to the memory module, and compared to biocod ...19892644450
dietary influences on disease resistance factors in channel catfish.the effects of diet on selected disease resistance factors were studied in channel catfish (ictalurus punctatus). two commercial feeds and a "control," laboratory-prepared diet were compared. macrophage function (phagocytosis and intracellular killing) was used to assess nonspecific disease resistance and serum antibody was measured as an indication of specific immunity. we measured the immune response to edwardsiella ictaluri, a common bacterial pathogen of catfish, as well as the phagocytosis ...19892767308
rapid plasmid analysis for identification of edwardsiella ictaluri from infected channel catfish (ictalurus punctatus).eighteen different strains of edwardsiella ictaluri isolated from infected channel catfish (ictalurus punctatus) were screened to determine whether plasmid dna was present. two plasmids of 5,700 and 4,900 base pairs were identified. restriction enzyme analysis showed that each of the strains harbored these same two plasmids. restriction maps of the separated plasmids indicated that these plasmids were not closely related to each other. a rapid screening technique was developed that would allow t ...19873038017
chemical characterization of lipopolysaccharide from edwardsiella ictaluri, a fish pathogen.the chemical components of lipopolysaccharide (lps) from the fish pathogen edwardsiella ictaluri (ed. ictaluri) were analyzed by sds-page, gas chromatography, and spectrophotometry, and compared with those of salmonella typhimurium and escherichia coli 0111:b4. only four to five low molecular weight species of lps from ed. ictaluri were detected by silver staining after separation by polyacrylamide gel electrophoresis. the low molecular weight species, as well as a low sugar content, indicate th ...19883208199
isolation, characterization, and molecular cloning of cryptic plasmids isolated from edwardsiella ictaluri.fifty-five isolates of edwardsiella ictaluri were examined for the presence of plasmid dna by a rapid alkaline extraction procedure. all 49 isolates from channel catfish and a single isolate from bengal danio carried 2 plasmids with molecular masses of approximately 3.2 and 3.7 megadaltons (mdal). five e ictaluri isolates from other fish contained 1 to 3 plasmids, which had molecular masses ranging from 2.5 to 45 mdal. the 2 plasmids (3.2 and 3.7 mdal) from the type strain of e ictaluri (atcc 33 ...19883247906
effect of water temperature on the clinical outcome of infection with edwardsiella ictaluri in channel catfish fingerlings (mean body weight, 19 +/- 3 g each) were given intraperitoneal inoculations of edwardsiella ictaluri suspensions of 10(4), 10(5), or 10(6) bacteria. control fish were inoculated intraperitoneally with sterile 0.85% nacl solution. ten-day trials were conducted at water temperatures of 17, 21, 23, 25, 28, and 32 c. differences in mortality between e ictaluri-infected fish and fish used as controls were observed at water temperatures of 23, 25, and 28 c, but not at tempe ...19873692982
antimicrobial susceptibility of edwardsiella ictaluri.edwardsiella ictaluri isolates collected over the past 7 yr from outbreaks of disease in fish occurring in different geographic areas were screened against 37 antimicrobial agents. edwardsiella ictaluri were found to be susceptible to most agents active against gram negative bacteria such as aminoglycosides, cephalosporins, the "newer" penicillins, quinolones, tetracyclines, chloramphenicol, nitrofurantoin, and potentiated sulfonamides. resistance was observed against colistin, sulfonamides, and ...19863712643
modulary effects of temperature on antibody response and specific resistance to challenge of channel catfish, ictalurus punctatus, immunized against edwardsiella ictaluri.the effects of various temperature treatments on the level of the humoral antibody response in channel catfish immunized with formalin killed edwardsiella ictaluri was determined in laboratory controlled experiments. immunized fish that were held at 25 degrees c for 30 days and 12 degrees c for an additional 30 days had higher antibody titers, and were more protected upon challenge, than immunized fish held at 25 degrees c for 60 days. also immunized catfish held at 25 degrees c for 5 or 10 days ...19863765350
exotic bacterial pathogens edwardsiella tarda and edwardsiella ictaluri from imported ornamental fish betta splendens and puntius conchonius, respectively: isolation and quarantine significance. 19863827773
biochemical characteristics of edwardsiella ictaluri.a total of 119 isolates of edwardsiella ictaluri collected over the last 7 years from several states were biochemically characterized. although not very reactive biochemically, this bacterium shows a high degree of homogeneity. differences were found only in the production of gas from formate or from glucose at 37 degrees c and in the production of hydrogen sulfide as detected by lead acetate paper. analysis of e. ictaluri by year of geographic area indicated that some differences existed, but n ...19863954336
elevated levels of dietary ascorbic acid increase immune responses in channel catfish fingerlings were fed purified diets containing 0 to 3000 mg/kg of ascorbic acid until external signs of scurvy were seen in the fish fed the ascorbic acid-deficient diet. at this time, resistance to bacterial infection, antibody production, complement activity and phagocytic activity were assessed for fish from the various dietary treatments. mortality rates of fish experimentally infected with edwardsiella ictaluri, the bacterium causing enteric septicemia in channel catfish, de ...19853965664
chemiluminescence by peripheral blood phagocytes from channel catfish: function of opsonin and temperature.the ability of the peripheral blood phagocytes from channel catfish, ictalurus punctatus, to produce chemiluminescence (cl) following ingestion of the enteric pathogen edwardsiella ictaluri was evaluated under a variety of opsonic and temperature conditions. the cl response was influenced by the concentration of immune serum used to opsonize the bacteria as well as the presence of nonspecific, heat labile opsonins. peak light emissions were diminished and the time to peak response was increased ...19854018342
pathology associated with a natural edwardsiella ictaluri infection in channel catfish (ictalurus punctatus rafinesque). 19846530729
influence of edwardsiella ictaluri septicemia on nitrite-induced methemoglobinemia in channel catfish (ictalurus punctatus). 19846743856
plasmid and serological differences between edwardsiella ictaluri strains.several studies have shown that isolates of edwardsiella ictaluri obtained from infected channel catfish in the southeastern united states harbor two cryptic plasmids, designated pcl1 (5.7 kb) and pcl2 (4.9 kb). these isolates appear to be serologically homogeneous. to extend these studies, we focused our analyses on two isolates of nonictalurid origin. plasmid analyses of a danio isolate showed that it harbored plasmids which were similar if not identical to pcl1 and pcl2. this strain was also ...19937692817
immunotoxicity in channel catfish, ictalurus punctatus, following acute exposure to tributyltin.tributyltin (tbt) is a trialkylated organotin formulated for use primarily as a biocide for aquatic and agricultural industries. although macrophages isolated from toadfish (opsanus tau) are sensitive to exposure, very little is known about the effects of tbt on fish humoral immunity and non-specific cytotoxic cell (ncc) functions. to evaluate the effects of tbt on these parameters, channel catfish (ictalurus punctatus) were given a single intraperitoneal injection of corn oil with 0 (vehicle co ...19957755401
protection against enteric septicemia of catfish (ictalurus punctatus) by immunization with the r-mutant, escherichia coli (j5).the protective effects of immunization with the rough (r) mutant, escherichia coli (j5), were evaluated in an experimental model of edwardsiella ictaluri-induced enteric septicemia of catfish (ictalurus punctatus). groups of 18 to 25 fish were administered killed e coli (j5) with or without an aluminum hydroxide (alum) adjuvant by intraperitoneal (i.p.) or im route. vaccinated fish were experimentally infected with virulent ed ictaluri. fish were monitored to determine survival after ed ictaluri ...19947802393
opsonic effect of the alternative complement pathway on channel catfish peripheral blood phagocytes.this study determined the effect of the alternative complement pathway (acp) on neutrophil and monocyte phagocytes from peripheral blood of channel catfish, ictalurus punctatus. fluorescent-labeled latex microspheres, edwardsiella ictaluri and escherichia coli were used to quantify phagocytic attachment and ingestion. activation of the acp enhanced the attachment of bacteria and microspheres to neutrophils and monocytes. activation of the acp by serum opsonization of escherichia coli increased i ...19938116220
rapid enzyme-linked immunosorbent tests for detecting antibodies to edwardsiella ictaluri in channel catfish, ictalurus punctatus, using exoantigen.a rapid enzyme-linked immunosorbent assay (elisa) was developed to evaluate sera from channel catfish with and without edwardsiella ictaluri infection. anti-e. ictaluri antibodies were detected in the sera from 94 of 100 infected catfish. specific antibodies were not detected in the sera from 100 non-infected fish. the elisa was based on the falcon assay screening test (fast) and was performed in 30 min. an e. ictaluri exoantigen was used in the fast-elisa. the immunodominance of the exoantigen ...19938333144
immunization with bacterial antigens: edwardsiellosis.enteric septicaemia of catfish (esc), caused by edwardsiella ictaluri, is the most serious disease affecting commercial catfish culture in the united states. esc is generally an acute septicaemia that develops very quickly, especially in the temperature range of 22-28 degrees c, with a more chronic disease presentation outside this range. the ability of e. ictaluri to avoid the host's immune system and proliferate into a systemic infection is impressive. catfish kidney tissue cultured positive f ...19979270841
quantification of immunoglobulin in the serum and mucus of channel catfish at different ages and following infection with edwardsiella enzyme-linked immunosorbent assay was developed to quantify immunoglobulin (ig) in the serum and mucus of channel catfish (ictalurus punctatus). the capture antibody (ab) was a monoclonal ab to channel catfish ig and the detector was a polyclonal goat serum against channel catfish ig. detectable levels of channel catfish ig were 0.1 microgram ml-1 and coefficients of intra- and interassay variations were 20% and 15%, respectively. serum ig concentration was found to increase from 0.36 +/- 0.2 ...19979336885
killing of edwardsiella ictaluri by macrophages from channel catfish immune and susceptible to enteric septicemia of catfish.the role of peritoneal macrophages in immunity to enteric septicemia of catfish (esc) after infection with live edwardsiella ictaluri was investigated. channel catfish macrophage-mediated bacteriocidal activity was dependent on the macrophage:bacteria ratio. ratios of 1:1 to 1:12 exhibited significant differences (p < or = 0.05) in killing between macrophages from immune fish when compared to killing by macrophages from susceptible fish at 2.5 h. at 5 h, macrophages from immune fish were capable ...19979336886
attenuation, persistence, and vaccine potential of an edwardsiella ictaluri pura this study, an adenine-auxotrophic strain of edwardsiella ictaluri was constructed and its virulence, tissue persistence, and vaccine efficacy were evaluated. a clone containing the pura gene was isolated from an e. ictaluri genomic library, sequenced, and shown to have an overall sequence identity of 79.3% at the nucleotide level and 85.7% at the amino acid level with the escherichia coli pura gene. the cloned e. ictaluri pura gene was mutated by deleting a 598-bp segment of the gene and ins ...19979353045
in vivo modulation of innate resistance to edwardsiella ictaluri with a phosphatase inhibitor.catfish were treated with the protein phosphatase inhibitor sodium orthovanadate (vanadate) and challenged with the pathogen edwardsiella ictaluri to investigate the relationship between the in vivo immunoregulatory effects of tyrosine and serine phosphatases on nonspecific modulation of resistance to bacterial infections. two different infection protocols were used: fish were pretreated by immersion in vanadate and subsequently infected (by immersion) with 1 ld100 e. ictaluri, or fish were inje ...19989678967
pharmacokinetics of oxytetracycline in the red pacu (colossoma brachypomum) following different routes of administration.oxytetracycline (otc) pharmacokinetics were studied in the red pacu (colossoma brachypomum) following intravenous (i.v.) and intramuscular (i.m.) administration at a dose of 5 mg/kg body weight. otc plasma concentrations were determined by high-performance-liquid-chromatography (hplc). a non-compartmental model was used to describe plasma drug disposition after otc administration. following i.m. administration, the elimination half-life (t1/2) was 62.65 +/- 1.25 h and the bioavailability was 49. ...19989811436
development and use of modified live edwardsiella ictaluri vaccine against enteric septicemia of catfish.the present study showed that e. ictaluri re-33 vaccine does not cause esc but does stimulate protective immunity. the re-33 vaccinates were protected against esc for at least 4 months following a single bath immersion in a low number of e. ictaluri re-33 without booster vaccination. antibody responses are weak after re-33 vaccination. edwardsiella ictaluri re-33 vaccine presents no risk or hazard to catfish. re-33 vaccine will prevent esc caused by most isolates of e. ictaluri in catfish. we re ...19999890040
characterization and expression of an eb1 protein in ictalurus punctatus neutrophils.we have identified an eb1 gene (cfeb1) and protein in channel catfish neutrophils. the complete cdna sequence is 1725 bp and the putative protein is composed of 258 amino acids. western blot analysis of channel catfish neutrophil cell membrane with a monoclonal antibody (14i) yielded a 28 kd protein band with the protein preparation. aside from neutrophils only a small percentage of other cells tested expressed detectable amounts of eb1 as determined by flow cytometry. furthermore, eb1 expressio ...200010906387
survivability and immune responses after challenge with edwardsiella ictaluri in susceptible and resistant families of channel catfish, ictalurus punctatus.diseases in catfish farming are prevalent and costly, particularly the bacterial disease enteric septicemia of catfish. considerable research has focused on different aspects of this disease, including the biology of the causative agent, edwardsiella ictaluri. however, no satisfactory treatment or preventive has resulted from these efforts. one solution is to increase the natural disease resistance of the fish through genetic selection. recent research has demonstrated that genetic factors influ ...200011016583
sequencing and analysis of the edwardsiella ictaluri determine possible functions of the edwardsiella ictaluri plasmids, pei1 and pei2, we analyzed the sequence of both plasmids. plasmid pei1 is 4807 bp, with 51% g + c, and 23 possible open reading frames of 40 amino acids or greater. plasmid pei2 is 5643 bp, with 51% g + c, and 24 possible reading frames. database searches indicated that pei1 contains an insertion element and a rom analog. in addition, pei1 possesses an open reading frame with strong homology to slrp, ssph1, and ssph2 of salmo ...200111319932
rapid detection of columnaris disease in channel catfish (ictalurus punctatus) with a new species-specific 16-s rrna gene-based pcr primer for flavobacterium columnare.a 16-s rrna gene from the chromosomal dna of the fish-pathogenic bacterium flavobacterium columnare (formerly flexibacter columnaris), strain ars-i, was cloned, sequenced and used to design a polymerase chain reaction (pcr) primer set. the primer set amplified a specific 1193-bp dna fragment from f. columnare strains but not from related bacteria, f. psychrophilum, f. aquatile, f. branchiophilum, or other bacterial pathogens of fish, flexibacter maritimus, cytophaga johnsonae, edwardsiella ictal ...200312459241
edwardsiella ictaluri invasion of iec-6, henle 407, fathead minnow and channel catfish enteric epithelial cells.invasion of edwardsiella ictaluri into cultured mammalian, fish and enzymatically harvested catfish enteric epithelial cells is described. gentamicin survival assays were used to demonstrate the ability of this catfish pathogen to invade iec-6 (origin: rat small intestinal epithelium), henle 407 (origin: human embryonic intestinal epithelium), fathead minnow (fhm, minnow epithelial cells) and trypsin/pepsin-harvested channel catfish enteric epithelial cells. invasion of all cell types occurred w ...200212465874
cloning and characterization of edwardsiella ictaluri proteins expressed and recognized by the channel catfish ictalurus punctatus immune response during edwardsiella ictaluri expression library was screened for clones expressing antigenic e. ictaluri proteins using anti-e. ictaluri serum, which resulted in the isolation of 32 clones. the clones were partially characterized and 4 were selected for complete analysis. sodium dodecyl sulfate polyacrylamide gel electrophoresis (sds-page), 2-dimensional page, western blotting, and dna sequencing were used to analyze expressed antigenic proteins and encoded genes. sequence analysis identified 4 puta ...200212542086
infection-blocking genes of a symbiotic rhizobium leguminosarum strain that are involved in temperature-dependent protein secretion.rhizobium leguminosarum strain rbl5523 is able to form nodules on pea, but these nodules are ineffective for nitrogen fixation. the impairment in nitrogen fixation appears to be caused by a defective infection of the host plant and is host specific for pea. a tn5 mutant of this strain, rbl5787, is able to form effective nodules on pea. we have sequenced a 33-kb region around the phage-transductable tn5 insertion. the tn5 insertion was localized to the 10th gene of a putative operon of 14 genes t ...200312580282
the edwardsiella ictaluri o polysaccharide biosynthesis gene cluster and the role of o polysaccharide in resistance to normal catfish serum and catfish neutrophils.edwardsiella ictaluri, the causative agent of enteric septicaemia of catfish (esc), expresses long o polysaccharide (ops) chains on its surface. the authors previously reported the construction of an isogenic ed. ictaluri ops mutant strain and demonstrated that this strain is avirulent in channel catfish. this paper reports the cloning of the ed. ictaluri ops biosynthesis gene cluster and identification of the mutated gene in the ops-negative strain. the sequenced region contains eight complete ...200312777482
a comparative study of edwardsiella ictaluri parent (eilo) and e. ictaluri rifampicin-mutant (re-33) isolates using lipopolysaccharides, outer membrane proteins, fatty acids, biolog, api 20e and genomic analyses.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). o ...200312946011
pathogen loads, clearance and plasma cortisol response in channel catfish, ictalurus punctatus (rafinesque), following challenge with edwardsiella ictaluri. 200312946014
safety of aquaflor (florfenicol, 50% type a medicated article), administered in feed to channel catfish, ictalurus punctatus.aquaflor, a feed premix containing the broad spectrum antibacterial agent florfenicol (50% w/w), is being developed for use to control enteric septicemia (esc) in channel catfish ictalurus punctatus caused by the gram-negative enterobacterium edwardsiella ictaluri. the recommended dose of aquaflor to control esc is 10 mg/kg body weight (bw)/day for 10 days. the study objective was to determine the safety of aquaflor administered in feed to channel catfish at doses of 0 (control), 10, 30, and 50 ...200314585738
in vitro evaluation of the susceptibility of edwardsiella ictaluri, etiological agent of enteric septicemia in channel catfish, ictalurus punctatus (rafinesque), to vitro studies were conducted to assess the sensitivity of edwardsiella ictaluri, the etiological agent of enteric septicemia of catfish (esc), to the antibacterial drug florfenicol (ffc). twelve different e. ictaluri isolates from cases submitted between 1994 and 1997 to the thad cochran national warmwater aquaculture center fish diagnostic laboratory (stoneville, ms) were used for testing. these isolates originated from channel catfish (ictalurus punctatus) infected with e. ictaluri through ...200314667023
purification of antimicrobial factor from granules of channel catfish peripheral blood leucocytes.the channel catfish (ictalurus punctatus) is extensively used in aquaculture in the southeast us and is susceptible to many bacterial infections acquired from its pond environment. research is needed to better understand the defensive response and innate immunity of channel catfish against fish pathogens like edwardsiella ictaluri and aeromonas hydrophila. the main objectives were purification and characterization of an innate antimicrobial factor isolated from catfish leucocytes that has both b ...200414672693
enhanced bacterial disease resistance of transgenic channel catfish ictalurus punctatus possessing cecropin genes.the cecropin b gene from the moth hyalophora cecropia, driven by the cytomegalovirus promoter, was transferred to the channel catfish ictalurus punctatus. transgenic individuals (p1) were mated to produce individuals (f1) that exhibited enhanced disease resistance and survival when challenged with pathogenic bacteria. during the epizootic of flavobacterium columnare in an earthen pond, the percentage of transgenic individuals containing preprocecropin b construct that survived (100%) was signifi ...200214961267
sequence analysis and expression of a cxc chemokine in resistant and susceptible catfish after infection of edwardsiella ictaluri.chemokines represent a superfamily of chemotactic cytokines involved in recruitment, activation and adhesion of a variety of leukocyte types to inflammatory foci. we cloned and sequenced the cdna of a cxc chemokine that is most similar to cxcl10 from channel catfish and blue catfish. sequence analysis of pcr amplicons from a single f1 hybrid catfish indicated that channel catfish and blue catfish may have a multigene family for the cxc chemokine. the catfish cxc chemokine was expressed in a wide ...200415043945
immune response induced by n-lauroylsarcosine extracted outer-membrane proteins of an isolate of edwardsiella ictaluri in channel catfish.a virulent isolate of edwardsiella ictaluri (al-93-75), the causative agent of enteric septicaemia of catfish (esc), was used to derive a lipopolysaccharide-reduced n-lauroylsarcosine outer-membrane protein (omp) fraction vaccine. the omp fraction was analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) and compared to whole-cell lysate, purified lipopolysaccharide (lps) and a crude cell-wall fraction. the omp fraction contained less than 2% (w/v) lps. sds-page sho ...200415123308
in vitro inhibitory effect of gossypol from gossypol-acetic acid, and (+)- and (-)-isomers of gossypol on the growth of edwardsiella ictaluri.this study was conducted to evaluate the toxic effect of gossypol from gossypol-acetic acid, and (+)- and (-)-isomers of gossypol on the growth of edwardsiella ictaluri.200415186445
use of proteomics to identify novel virulence determinants that are required for edwardsiella tarda pathogenesis.edwardsiella tarda is an important cause of haemorrhagic septicaemia in fish and also of gastro- and extraintestinal infections in humans. using a combination of comparative proteomics and tnphoa mutagenesis, we have identified five proteins that may contribute to e. tarda ppd130/91 pathogenesis. lowered protein secretion, impaired autoaggregation and the absence of six proteins were observed only in three highly attenuated mutants when cultured in dulbecco's modified eagle medium (dmem). five o ...200415228535
analysis of a catfish gene resembling interleukin-8: cdna cloning, gene structure, and expression after infection with edwardsiella ictaluri.chemokines are important mediators for innate immunity involved in recruitment, activation and adhesion of a variety of leukocyte types to inflammatory foci. while almost all chemokines have been identified from mammals, only a handful of fish chemokines have been identified. here we report molecular cloning, sequence analysis, and expression of a channel catfish gene resembling interleukin-8 (il-8). the gene has two alternatively spliced transcripts encoding 114 and 111 amino acids, respectivel ...200515450753
a thermostable variant of fructose bisphosphate aldolase constructed by directed evolution also shows increased stability in organic solvents.thermostable variants of the class ii fructose bisphosphate aldolase have been isolated following four rounds of directed evolution using dna shuffling of the fda genes from escherichia coli and edwardsiella ictaluri. variants from all four generations of evolution have been purified and characterized. the variants show increased thermostability with no loss of catalytic function at room temperature. the temperature at which 50% of the initial enzyme activity is lost after incubation for 10 min ...200415531627
activation of tlr3 and tlr5 in channel catfish exposed to virulent edwardsiella ictaluri.two toll-like receptors (tlr3 and tlr5) were identified from a catfish cdna fry library based on sequence similarity to other vertebrate tlr genes. expression (using real-time pcr) of tlr3 and tlr5 was measured for two strains of channel catfish in previously non-exposed fish 2, 5, 8, and 21 days after experimental edwardsiella ictaluri challenge to determine if tlrs are associated with host response to e. ictaluri infection. expression of tlr5 was higher than tlr3 (p<0.0001). tlr3 expression in ...200415854683
effects of cortisol and stress on channel catfish (ictalurus punctatus) pathogen susceptibility and lysozyme activity following exposure to edwardsiella ictaluri.periods of stress are often associated with disease outbreaks in cultured fish, and stress is often characterized by the secretion of cortisol. although stress and cortisol secretion are highly correlated in fish, the role of cortisol in affecting channel catfish (ictalurus punctatus) pathogen susceptibility is unclear. the effects of short-term stress and exogenous cortisol administration on channel catfish susceptibility to edwardsiella ictaluri, the etiologic agent of enteric septicemia of ca ...200515862571
the structure of the antigenic o-polysaccharide of the lipopolysaccharide of edwardsiella ictaluri strain mt104.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.200515882848
characterization and expression analysis of bactericidal permeability-increasing protein (bpi) antimicrobial peptide gene from channel catfish ictalurus punctatus.antimicrobial peptides are important components of host defenses against microbial invasions. bactericidal permeability-increasing protein (bpi) is an antimicrobial peptide belonging to the lipid transfer/lps-binding protein family. it serves important roles in defending against gram-negative bacteria in the innate immune system. here we report cloning of complete bpi cdna from channel catfish (ictalurus punctatus) by 5' race after obtaining the partial bpi cdna sequence from est analysis. the c ...200515896843
response of toll-like receptors, lysozyme, and igf-i in back-cross hybrid (f1 male (blue x channel) x female channel) catfish challenged with virulent edwardsiella ictaluri.responses of toll-like receptors (tlr3 and tlr5), lysozyme, and insulin-like growth factor-i (igf-i) to experimental challenge with virulent edwardsiella ictaluri were measured in back-cross hybrid (f1 male (blue x channel) x female channel) catfish. the resistance levels to e. ictaluri and host response mechanisms of back-cross hybrids are unknown. fish were challenged with virulent e. ictaluri and sampled pre-challenge, 2 h and 2, 5, 8, 14, and 21 days post-challenge. levels of mrna expression ...200615905103
identification and characterization of a two-component hemolysin from edwardsiella ictaluri.the channel catfish pathogen edwardsiella ictaluri possesses hemolysin activity, and strains that are adapted for growth in fish tend to have greater hemolysin activity than strains that are adapted for in vitro growth conditions. to investigate its potential role in virulence, an isogenic hemolysin mutant strain of e. ictaluri r4383 was constructed by transposon mutagenesis. sequencing of the chromosomal insertion site identified two genes, designated eiha and eihb, that encode proteins with ho ...200515923091
catfish hepcidin gene is expressed in a wide range of tissues and exhibits tissue-specific upregulation after bacterial infection.antimicrobial peptides (amps) are important components of the host innate immune response against microbial invasion. the cysteine-rich amps such as defensin and hepcidin have been extensively studied from various organisms, but their role in disease defense in catfish is unknown. as a first step, we sequenced a hepcidin cdna from both channel catfish and blue catfish, and characterized the channel catfish hepcidin gene. the channel catfish hepcidin gene consists of two introns and three exons t ...200515935472
constitutive expression of three novel catfish cxc chemokines: homeostatic chemokines in teleost fish.chemokines are best known for their vital role in leukocyte chemotaxis, as part of the larger inflammatory response. expression analysis and functional characterization of chemokines in mammalian species have often overlooked the role of these proteins under homeostatic conditions. recent investigations of chemokine diversity in teleost fish have also centered on the immune-related functions of chemotactic cytokines, such as cxcl8 and cxcl10. while a disease-based approach to chemokines is essen ...200515950731
bacterial vaccines for fish--an update of the current situation worldwide.during the last few years, the use of vaccines for disease prevention in aquaculture has expanded both with regard to the number of fish species and number of microbial diseases. according to the responses to a questionnaire received from 41 countries, vaccination is used in the commercial aquaculture of species like atlantic salmon (salmo salar), rainbow trout (oncorhynchus mykiss), sea bass (dicentrarchus labrax), sea bream (sparus aurata), barramundi (lates calcarifer), tilapia (tilapia spp), ...200515962470
warmwater fish vaccinology in catfish production.the ability of the fish industry to provide a continuous supply of fish protein depends on both proper biosecurity and strategies to significantly reduce the risk of infectious diseases. vaccination is a safe and effective means to prevent disease and to increase the productivity and profitability of farmed fish. vaccines are likely to be the prime prophylactic measure of the future because of rapidly developing advances in fish vaccine technology and producer acceptance. the efficacy of a vacci ...200415984345
analysis of 16s-23s intergenic spacer regions of the rrna operons in edwardsiella ictaluri and edwardsiella tarda isolates from analyse interspecies and intraspecies differences based on the 16s-23s rrna intergenic spacer region (isr) sequences of the fish pathogens edwardsiella ictaluri and edwardsiella tarda.200516108808
evaluation of a loop-mediated isothermal amplification method for rapid detection of channel catfish ictalurus punctatus important bacterial pathogen edwardsiella catfish ictalurus punctatus infected with edwardsiella ictaluri results in 40--50 million dollars annual losses in profits to catfish producers. early detection of this pathogen is necessary for disease control and reduction of economic loss. in this communication, the loop-mediated isothermal amplification method (lamp) that amplifies dna with high specificity and rapidity at an isothermal condition was evaluated for rapid detection of e. ictaluri. a set of four primers, two outer and t ...200516157211
genomic organization, gene duplication, and expression analysis of interleukin-1beta in channel catfish (ictalurus punctatus).interleukin-1beta (il-1beta) is one of the pivotal early response pro-inflammatory cytokines that enables organisms to respond to infection and induces a cascade of reactions leading to inflammation. in spite of its importance and two decades of studies in the mammalian species, genes encoding il-1beta were not identified from non-mammalian species until recently. recent research, particularly with genomic approaches, has led to sequencing of il-1beta from many species. clinical studies also sug ...200616280165
the catfish liver-expressed antimicrobial peptide 2 (leap-2) gene is expressed in a wide range of tissues and developmentally regulated.antimicrobial peptides (amps) are important components of the host's innate immune response against microbial invasion. the cysteine-rich amps such as defensin and hepcidin have been extensively studied, but the recently identified cysteine-rich liver-expressed antimicrobial peptide 2 (leap-2) has been characterized from only a few organisms. here we cloned and sequenced the leap-2 cdnas from both channel catfish and blue catfish. the leap-2 gene from channel catfish was also sequenced and chara ...200616310050
fate of fluorescent microspheres in developing ictalurus punctatus following prolonged immersion.particulate antigen uptake by the mucosa of developing channel catfish was determined by immersing larvae and fry [2-day post-hatch (dph), 1-, 2-, 3-, 4-, and 8-week post-hatch (wph)] to two forms of fluorescent microspheres (fms): blue fms were carboxylated, and green fms were coated via conjugation with a crude extract of edwardsiella ictaluri outer membrane protein (omp). phagocytosis, destination, and clearance appeared similar for the two types of fms used. in the older age classes, primary ...200616326113
catfish cc chemokines: genomic clustering, duplications, and expression after bacterial infection with edwardsiella ictaluri.chemokines are a family of structurally related chemotactic cytokines that regulate the migration of leukocytes, under both physiological and inflammatory conditions. cc chemokines represent the largest subfamily of chemokines with 28 genes in mammals. sequence conservation of chemokines between teleost fish and higher vertebrates is low and duplication and divergence may have occurred at a significantly faster rate than in other genes. one feature of cc chemokine genes known to be conserved is ...200616341548
development of a defined minimal medium for the growth of edwardsiella this report, a complete defined medium and a minimally defined medium are described for edwardsiella ictaluri. the complete defined medium consists of 46 individual components, including a basal salt solution, glucose, magnesium sulfate, iron sulfate, six trace metals, four nucleotides, 10 vitamins, and 19 amino acids. this medium supports growth in broth and on solid media. optimal growth at 30(deg)c was obtained at ph 7.0, and at an osmolality of 390 mosmol/kg of h(inf2)o, with a glucose co ...199616535274
immunofluorescent test for simultaneous detection of edwardsiella ictaluri and flavobacterium columnare.enteric septicemia of catfish (esc) and columnaris disease are 2 bacterial diseases significantly affecting the aquaculture industry, and thus rapid diagnosis of disease is imperative for making judicious management decisions. a rapid indirect fluorescent antibody (ifa) test with antibody conjugated fluorochromes having 2 different spectral properties (alexa fluor 488-emitting green fluorescence, and alexa fluor 594-emitting red fluorescence) was compared with bacteriological culture (accepted s ...200616610585
identification and characterization of an intervening sequence within the 23s ribosomal rna genes of edwardsiella ictaluri.comparison of the 23s rrna gene sequences of edwardsiella tarda and edw. ictaluri confirmed a close phylogenetic relationship between these two fish pathogen species and a distant relation with the 'core' members of the enterobacteriaceae family. analysis of the rrl gene for 23s rrna in edw. ictaluri revealed the presence of an intervening sequence (ivs) in helix-45. this new 98bp ivs shared 97% nucleotide identity with salmonella typhimurium helix-45 ivs. edw. ictaluri helix-45 ivs was present ...200716697134
development of bioluminescent edwardsiella ictaluri for noninvasive disease monitoring.edwardsiella ictaluri is a facultative intracellular bacterium that causes enteric septicemia of catfish (esc). in this study, we aimed to develop bioluminescent e. ictaluri that can be monitored by noninvasive bioluminescence imaging (bli). to accomplish this, the luxcdabe operon of photorhabdus luminescens was cloned downstream of the lacz promoter in the broad host range plasmid pbbr1mcs4. edwardsiella ictaluri strain 93-146 transformed with the new plasmid, paklux1, was highly bioluminescent ...200616842347
mortality and pathology in brown bullheads amieurus nebulosus associated with a spontaneous edwardsiella ictaluri outbreak under tank culture conditions.brown bullheads amieurus nebulosus (family ictaluridae) are commonly used as a sentinel of environmental contamination. these fish are not generally cultured under laboratory conditions and little is known about their disease susceptibility. here we report an outbreak of disease due to edwardsiella ictaluri in a laboratory population of tank-reared, wild-caught brown bullheads. the isolate was positively identified as e. ictaluri using standard bacteriological substrate utilization tests and a m ...200616903233
toll-like receptor 3 and ticam genes in catfish: species-specific expression profiles following infection with edwardsiella ictaluri.toll-like receptors (tlrs) are a family of transmembrane proteins that recognize specific pathogen-associated molecular patterns and use conserved signaling pathways to activate proinflammatory cytokines and type-1 interferons to fight infection. tlr3 in mammals is best known for its recognition of dsrna as ligand and its myd88-independent signaling. tlr3, upon recognition of dsrna, recruits and binds its adaptor protein tir domain-containing adapter molecule (ticam) 1. here we report the genomi ...200616969679
effects of gh on immune and endocrine responses of channel catfish challenged with edwardsiella ictaluri.the effects of gh on immune and endocrine responses to channel catfish challenged with the bacterium edwardsiella ictaluri were examined. catfish (11.7+/-1.0 g) treated with recombinant bovine growth hormone (rbgh) and challenged with e. ictaluri experienced similar mortality as control-exposed fish. plasma activity of lysozyme was higher (p<0.01) in rbgh-exposed fish. compared to day 0 controls (non-exposed fish), igf-i levels decreased (p<0.05) in challenged fish while levels were similar (p>0 ...200717030140
immunization of eyed channel catfish, ictalurus punctatus, eggs with monovalent flavobacterium columnare vaccine and bivalent f. columnare and edwardsiella ictaluri vaccine.the efficacy of a modified live monovalent flavobacterium columnare vaccine and bivalent f. columnare and edwardsiella ictaluri vaccines were evaluated following immersion vaccination of eyed channel catfish (ictalurus punctatus) eggs. the modified live f. columnare vaccine was grown in modified shieh broth and administered at 1.35 x 10(7) cfu/ml for 15 min exposure (1l water). booster immunization was conducted at day 34 with 2.17 x 10(7) cfu/ml for 15 min. bivalent vaccines consisted of a 1:1 ...200717050050
structural characterisation and expression analysis of toll-like receptor 2 gene from catfish.toll-like receptors (tlrs) are important components of innate immunity. they were found to recognise specific structures on pathogens termed pathogen-associated molecular patterns (pamps) and utilise conserved signaling pathways to activate pro-inflammatory cytokines and type-1 interferons. in spite of much understanding gained from the mammalian systems, many fish tlrs are unknown. recent studies in japanese flounder as well as in zebrafish suggested that the ligand binding and activation of in ...200717116407
channel catfish hepcidin expression in infection and anemia.hepcidin, originally identified as a 25 amino acid antimicrobial peptide made in the liver, is a key regulator of iron balance and recycling in humans and mice. closely related hepcidin genes and peptides have also been identified in a number of fish species and in teleosts are thought to function as endogenous antibiotics involved in host defense against infection. here we report the transcriptional regulation of hepcidin expression by infection and anemia in the channel catfish. changes in hep ...200717126400
improvement of aquaculture wastewater using chitosan of different degrees of deacetylation.removal of organic compounds and inorganic nutrients from aquaculture wastewaters prior to discharge can not only minimize deterioration of receiving water quality, but it could also be further reused to culture prawn, fish and shellfish. chitosan can be used as a coagulant, adsorbent, or bactericide; therefore it has been used to improve aquaculture wastewater quality as it could remove suspended solids (ss), organic compounds, nh3, po43-, and pathogens. the best performance of chitosan in remo ...200617203601
expression analysis of the acute phase response in channel catfish (ictalurus punctatus) after infection with a gram-negative bacterium.the acute phase response (apr) is a set of metabolic and physiological reactions occurring in the host in response to tissue infection or injury and is a crucial component of the larger innate immune response. the apr is best characterized by dramatic changes in the concentration of a group of plasma proteins known as acute phase proteins (apps) which are synthesized in the liver and function in a wide range of immunity-related activities. utilizing a new high-density in situ oligonucleotide mic ...200717449095
multiplex-pcr for simultaneous detection of 3 bacterial fish pathogens, flavobacterium columnare, edwardsiella ictaluri, and aeromonas hydrophila.a multiplex pcr (m-pcr) method was developed for simultaneous detection of 3 important fish pathogens in warm water aquaculture. the m-pcr to amplify target dna fragments from flavobacterium columnare (504 bp), edwardsiella ictaluri (407 bp) and aeromonas hydrophila (209 bp) was optimized by adjustment of reaction buffers and a touchdown protocol. the lower detection limit for each of the 3 bacteria was 20 pg of nucleic acid template from each bacteria per m-pcr reaction mixture. the sensitivity ...200717465305
microarray analysis of gene expression in the blue catfish liver reveals early activation of the mhc class i pathway after infection with edwardsiella ictaluri.the acute nature of disease outbreaks in aquaculture settings has served to emphasize the importance of the innate immune response of fish for survival and led to the recent identification and characterization of many of its components. catfish, the predominant aquaculture species in the united states, is an important model for the study of the teleost immune system. however, transcriptomic-level studies of disease-related gene expression in catfish have only recently been initiated, and underst ...200817599411
susceptibility of channel catfish, ictalurus punctatus (rafinesque), to edwardsiella ictaluri challenge following copper sulphate catfish, ictalurus punctatus (rafinesque), with or without a preliminary 24 h exposure to 2 mg copper sulphate l(-1), were challenged with 7.5 x 10(6) colony forming units l(-1) of edwardsiella ictaluri to determine the effect of copper sulphate on disease resistance. catfish previously exposed to copper sulphate were significantly more resistant to the bacterial challenge than those not exposed. catfish not exposed to copper sulphate suffered 35.5% mortality while catfish exposed to cop ...200717850574
comparative study of mannose-binding c-type lectin isolated from channel catfish (ictalurus punctatus) and blue catfish (ictalurus furcatus).mannose-binding c-type lectin (mbl) was isolated from channel catfish (ictalurus punctatus) nwac 102 and 103 strains, blue catfish (ictalurus furcatus) d+b and rio grande strains, hybrid catfish (channel catfish female nwac 103 x blue catfish male d+b) sera, and purified by affinity chromatography from channel catfish norris strain serum. reduction of purified channel catfish mbl with 2-me yielded a single band of 62 kda by sds-page and western blot analysis using guinea pig anti-mbl igg as prim ...200717950622
signature-tagged mutagenesis of edwardsiella ictaluri identifies virulence-related genes, including a salmonella pathogenicity island 2 class of type iii secretion systems.edwardsiella ictaluri is the leading cause of mortality in channel catfish culture, but little is known about its pathogenesis. the use of signature-tagged mutagenesis in a waterborne infection model resulted in the identification of 50 mutants that were unable to infect/survive in catfish. nineteen had minitransposon insertions in miscellaneous genes in the chromosome, 10 were in genes that matched to hypothetical proteins, and 13 were in genes that had no significant matches in the ncbi databa ...200717965213
channel catfish, ictalurus punctatus, cyclophilin a and b cdna characterization and expression analysis.the preliminary observation of up-regulation of cyclophilin transcripts during edwardsiella ictaluri infection prompted us to speculate on the potential importance of cyclophilins in the early stage of infection. to provide a framework for answering these questions, two cyclophilin cdna of channel catfish, ictalurus punctatus, were identified, sequenced and characterized. the complete nucleotide sequences of cyclophilin a and cyclophilin b cdna consisted of 1170 and 996 bases, respectively. anal ...200818001845
differences in mortality, growth, lysozyme, and toll-like receptor gene expression among genetic groups of catfish exposed to virulent edwardsiella ictaluri.survivorship to esc (enteric septicemia of catfish) varies among and within strains of commercially raised catfish, however the immunological basis for differences in susceptibility is not well-understood. we assessed the effect of pathogen challenge with edwardsiella ictaluri on five genetic groups of catfish by measuring both phenotypic response (mortality, pathogen levels, specific growth rate), and three measures of immune response, including lysozyme activity and mrna expression of two toll ...200818023209
the two channel catfish intelectin genes exhibit highly differential patterns of tissue expression and regulation after infection with edwardsiella ictaluri.intelectins (intl) are ca(2+)-dependent secretory glycoproteins that play a role in the innate immune response. the mammalian intl is also known as lactoferrin receptor (lfr) that is involved in iron metabolism. the objective of this study was to characterize the intelectin genes in both channel catfish and blue catfish, to determine their genomic organization and copy numbers, to determine their patterns of tissue expression, and to establish if they are involved in defense responses of catfish ...200818078992
evaluation of zebrafish danio rerio as a model for enteric septicemia of catfish (esc).zebrafish (also known as zebra danio) danio rerio were injected intramuscularly with edwardsiella ictaluri at doses of 6 x 10(3), 6 x 10(4), or 6 x 10(5) colony-forming units per gram (cfu/g) or sterile phosphate-buffered saline (sham) or were not injected. mortality occurred from 2 to 5 d postinjection (dpi) at rates of 0, 76.6, and 81.3% for the low, medium, and high doses, respectively, and e. ictaluri was isolated from dead fish. survivors were sampled at 10 dpi and e. ictaluri was not isola ...200718201056
characterization of the rrn operons in the channel catfish pathogen edwardsiella advance diagnostics and phylogenetics of edwardsiella ictaluri by sequencing and characterizing its rrn operons.200818217940
effects of variable periods of food deprivation on the development of enteric septicemia in channel catfish.enteric septicemia of catfish (esc), caused by the bacterium edwardsiella ictaluri, is the most significant bacterial disease affecting channel catfish ictalurus punctatus. withholding feed during outbreaks of esc is a widely accepted industry practice used to control losses from the disease. scientific evidence concerning the validity of the practice is contradictory. two studies were conducted to further evaluate the survival of channel catfish fingerlings following variable periods of feed de ...200818536501
molecular cloning, sequencing and characterization of channel catfish (ictalurus punctatus, rafinesque 1818) cathepsin s gene.cathepsin s is a lysosomal cysteine endopeptidase of the papain family. our preliminary results showed the up-regulation of cathepsin s (ctss) transcript during the early stage of edwardsiella ictaluri infection, leading us to speculate that ctss may play a role in infection. in this report, we identified, sequenced and characterized the channel catfish ctss cdna. total rna from tissues was isolated and cdna libraries were constructed by the rapid amplification cdna end (race) method. the gene-s ...200818817983
role of nonspecific cytotoxic cells in bacterial resistance: expression of a novel pattern recognition receptor with antimicrobial activity.pattern recognition receptors (prr) recognize invariant bacterial, viral, protozoan and certain synthetic ligands. prr may be expressed as outer membrane (or endosomal) or cytosolic proteins and function to signal cell activation processes during inflammation responses. in the present study, a novel membrane receptor, ncc cationic antimicrobial protein-1 (ncamp-1), is described that is expressed on nonspecific cytotoxic cell (ncc) membranes and is found in granule extracts from these cells. in r ...200919007992
proteomic analysis of head kidney tissue from high and low susceptibility families of channel catfish following challenge with edwardsiella ictaluri.a study was performed to compare proteomic profiles of channel catfish from families with high and low susceptibility to edwardsiella ictaluri following an immersion challenge. total protein was isolated from head kidney samples, collected at 2 and 6h postexposure, and analyzed by 2-d-gel electrophoresis coupled with peptide mass fingerprint analysis by matrix-assisted laser desorption/ionization and time of flight tandem mass spectrometry. comparisons were made between proteomic profiles from i ...200919028110
inca/c plasmid-mediated florfenicol resistance in the catfish pathogen edwardsiella ictaluri. 200919029319
channel catfish, ictalurus punctatus, cysteine proteinases: cloning, characterisation and expression of cathepsin h and l.the antigen recognition by the host immune system is a complex biochemical process that requires a battery of enzymes. cathepsins are one of the enzyme superfamilies involved in antigen degradation. we observed the up-regulation of catfish cathepsin h and l transcripts during the early stage of edwardsiella ictaluri infection in preliminary studies, and speculated that cathepsin h and l may play roles in infection. we identified, sequenced and characterized the complete channel catfish cathepsin ...200919084602
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