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invasive infection with streptococcus iniae--ontario, 1995-1996.during december 1995-february 1996, four cases of a bacteremic illness (three accompanied by cellulitis and the fourth with infective endocarditis, meningitis, and probable septic arthritis) were identified among patients at a hospital in ontario. streptococcus iniae, a fish pathogen not previously reported as a cause of illness in humans, was isolated from all four patients. all four patients were of chinese descent had a history of preparing fresh, whole fish; three patients for whom informati ...19968769472
from the centers for disease control and prevention. invasive infection with streptococcus iniae--ontario, 1995-1996. 19968782626
invasive infection due to streptococcus iniae: a new or previously unrecognized disease--ontario, 1995-1996. 19968791861
preliminary report: invasive infection due to streptococcus iniae. 19968911297
development and efficacy of a vaccine against streptococcus iniae infection in farmed rainbow trout.formalin killed bacteria were used as a vaccine against streptococcus iniae infections in farmed rainbow trout. a single intraperitoneal injection of this vaccine in trout resulted in specific antibody production detectable for 6 months. trout vaccinated at 50 g were protected under laboratory (experimental disease) and field conditions (natural disease) for at least 4 months against s. iniae infection. passive transfer of s. iniae specific antibodies conferred protection. under field conditions ...19979220590
immunization with bacterial antigens: infections with streptococci and related organisms.streptococcal infections of fish have been reported from various parts of the world, including the far east, the united states, south africa, australia, israel and europe. classification of gram-positive cocci (dna-dna hybridization studies coupled with 165 sequencing) has shown that at least five different defined species are pathogenic to fish, e.g. streptococcus iniae (syn. s. shilot), streptococcus difficile, lactococcus garvieae (syn. enterococcus seriolicida), lactococcus piscium and vagoc ...19979270844
invasive infections due to a fish pathogen, streptococcus iniae. s. iniae study group.streptococcus iniae is a pathogen in fish, capable of causing invasive disease and outbreaks in aquaculture farms. during the winter of 1995-1996 in the greater toronto area there was a cluster of four cases of invasive s. iniae infection in people who had recently handled fresh, whole fish from such farms.19979271480
food borne microbial pathogens of cultured aquatic species.this article provides a broad overview of microbial pathogens associated with marine and fresh water aquatic animals, including vibrio species, escherichia coli, streptococcus iniae, salmonella species, and edwardsiella tarda. historically, cultured fish were not considered important vectors of human pathogens. this situation is changing, partly due to increasing animal densities as a consequence of a rapidly growing industry and partly due to increasing awareness by health care providers of pat ...19989532670
identification of lactococcus garvieae by pcr.lactococcus garvieae junior synonym enterococcus seriolicida) is an emerging zoonotic agent isolated from economically important fish (rainbow trout and yellowtail), from cattle, and from humans. clindamycin susceptibility is the only phenotypic test which can differentiate l. garvieae from lactococcus lactis, another emerging agent in humans. a pcr assay for the identification of l. garvieae was developed and resulted in an amplified fragment of 1,100 bp in size. the pcr assay was shown to be s ...19989542921
streptococcus iniae, a human and animal pathogen: specific identification by the chaperonin 60 gene identification method.it was recently reported that streptococcus iniae, a bacterial pathogen of aquatic animals, can cause serious disease in humans. using the chaperonin 60 (cpn60) gene identification method with reverse checkerboard hybridization and chemiluminescent detection, we identified correctly each of 12 s. iniae samples among 34 aerobic gram-positive isolates from animal and clinical human sources.19989650992
development of specific nested oligonucleotide pcr primers for the streptococcus iniae 16s-23s ribosomal dna intergenic spacer.streptococcus iniae is a cause of septicemia, meningoencephalitis, and death in farmed fish and of cellulitis in human beings. a set of nested oligonucleotide pcr primers that specifically amplified a 373-bp subunit from a variety of clinical isolates from farmed fish and human patients were constructed from a 524-bp consensus sequence of the s. iniae 16s-23s ribosomal dna intergenic spacer.19989705438
possible transmission of streptococcus iniae from wild fish to cultured marine fish.streptococcus iniae was isolated from diseased wild fish collected near a mariculture facility where gilthead sea bream and european sea bass exhibited a similar infection. species-specific pcr and ribotyping confirmed that wild and cultured fish were infected by a single s. iniae clone. wild fish are therefore potential amplifiers of pathogenic s. iniae strains.19989758844
health and safety concerns in fisheries and aquaculture.only 10% of all foodborne illnesses in the united states are attributed to seafood, making seafood a relatively safe food commodity. the implementation of hazard analysis and critical control points guidelines should make seafood consumption even safer. concerns include closed-loop, indoor, water-recirculating production systems; harmful algal blooms in marine environments, which can cause paralytic, neurologic, amnesic, and diarrhetic shellfish poisonings and ciguatera fish poisoning; bacteria ...199910329911
lactococcus garvieae and streptococcus iniae infections in rainbow trout oncorhynchus mykiss: similar, but different diseases.clinical and macroscopic findings (anorexia, lethargy, loss of orientation and exophthalmia) indicate that streptococcus iniae and lactococcus garvieae infections of trout share some common features, but histopathology reveals notable differences between the 2 diseases. meningitis and panophthalmitis are the main lesions among s. iniae infected trout, whereas l. garvieae infection results in a hyperacute systemic disease. differences in the ld50s of the 2 pathogens and the sudden onset of signs ...199910401588
identification of enterococcus species and phenotypically similar lactococcus and vagococcus species by reverse checkerboard hybridization to chaperonin 60 gene sequences.data from four recent studies (s. h. goh et al., j. clin. microbiol. 36:2164-2166, 1998; s. h. goh et al., j. clin. microbiol. 34:818-823, 1996; s. h. goh et al., j. clin. microbiol. 35:3116-3121, 1997; a. y. c. kwok et al., int. j. syst. bacteriol. 49:1181-1192, 1999) suggest that an approximately 600-bp region of the chaperonin 60 (cpn60) gene, amplified by pcr with a single pair of degenerate primers, has utility as a potentially universal target for bacterial identification (id). this cpn60 ...200011060051
topically acquired bacterial zoonoses from fish: a review.the main pathogens acquired topically from fish (through spine puncture or open wounds) are aeromonas hydrophila, edwardsiella tarda, erysipelothrix rhusiopathiae, mycobacterium marinum, streptococcus iniae, vibrio vulnificus and vibrio damsela. s. iniae has recently emerged as a public health hazard associated with aquaculture, and m. marinum often infects home aquarium hobbyists. with the expansion of aquaculture and popularity of recreational fishing in australia, medical practitioners can ex ...200011130351
streptococcus iniae virulence is associated with a distinct genetic profile.streptococcus iniae causes meningoencephalitis and death in commercial fish species and has recently been identified as an emerging human pathogen producing fulminant soft tissue infection. as identified by pulsed-field gel electrophoresis (pfge), strains causing disease in either fish or humans belong to a single clone, whereas isolates from nondiseased fish are genetically diverse. in this study, we used in vivo and in vitro models to examine the pathogenicity of disease-associated isolates. s ...200111254550
streptococcus iniae inhibition of apoptosis of nonspecific cytotoxic cells: a mechanism of activation of innate immunity in teleosts.nonspecific cytotoxic cells (ncc) may provide innate anti-bacterial resistance against streptococcus iniae infections in tilapia. the mechanism of immunity would be elaboration and release of various cytokines, augmentation of inflammation and amplification of increased antigen processing. to investigate bacterial regulation of ncc function, 2 different processes of cellular pathology were examined: apoptosis and necrosis. different isolates of s. iniae from diseased teleosts, a dolphin and a hu ...200111592698
bass hepcidin is a novel antimicrobial peptide induced by bacterial challenge.we report the isolation of a novel antimicrobial peptide, bass hepcidin, from the gill of hybrid striped bass, white bass (morone chrysops) x striped bass (m. saxatilis). after the intraperitoneal injection of micrococcus luteus and escherichia coli, the peptide was purified from hplc fractions with antimicrobial activity against escherichia coli. sequencing by edman degradation revealed a 21-residue peptide (gcrfccnccpnmsgcgvccrf) with eight putative cysteines. molecular mass measurements of th ...200211985602
streptococcus-zebrafish model of bacterial pathogenesis.due to its small size, rapid generation time, powerful genetic systems, and genomic resources, the zebrafish has emerged as an important model of vertebrate development and human disease. its well-developed adaptive and innate cellular immune systems make the zebrafish an ideal model for the study of infectious diseases. with a natural and important pathogen of fish, streptococcus iniae, we have established a streptococcus- zebrafish model of bacterial pathogenesis. following injection into the ...200212065534
streptococcus iniae infections in red sea cage-cultured and wild fishes.streptococcus iniae was isolated from 2 moribund wild red sea fishes, pomadasys stridens (pomadasyidae) and synodus variegatus (synodontidae), both collected in shallow waters along the israeli coast of the gulf of eilat. the site is approximately 2 km from a mariculture cage farm in which streptococcal infections were diagnosed in previous years in the red drum sciaenops ocellatus. this is the first report of s. iniae in red sea fishes. biochemical and molecular similarities between the isolate ...200212113301
identification of a streptolysin s-associated gene cluster and its role in the pathogenesis of streptococcus iniae disease.streptococcus iniae causes meningoencephalitis and death in cultured fish species and soft-tissue infection in humans. we recently reported that s. iniae is responsible for local tissue necrosis and bacteremia in a murine subcutaneous infection model. the ability to cause bacteremia in this model is associated with a genetic profile unique to strains responsible for disease in fish and humans (j. d. fuller, d. j. bast, v. nizet, d. e. low, and j. c. s. de azavedo, infect. immun. 69:1994-2000, 20 ...200212228303
bacterial pathogens isolated from cultured bullfrogs (rana castesbeiana).a commercial bullfrog (rana castesbeiana) operation in south georgia had multiple epizootics of systemic bacterial infections over a 3-year period, 1998-2000. a number of potential pathogens (aeromonas hydrophila, chryseobacterium (flavobacterium) meningosepticum, chryseobacterium (flavobacterium) indolgenes, edwardsiella tarda, citrobacterfreundii, pseudomonas spp., and (streptococcus iniae) were isolated from various tissues. clinically, frogs demonstrated acute onset of torticolis, stupor, an ...200212296400
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
invasive streptococcus iniae infections outside north america.streptococcus iniae, a fish pathogen causing infections in aquaculture farms worldwide, has only been reported to cause human infections in north america. in this article, we report the first two cases of invasive s. iniae infections in two chinese patients outside north america. while the first patient presented with bacteremic cellulitis, which is the most common presentation in previous cases, the second patient represents the first recognized case of s. iniae osteomyelitis. both s. iniae str ...200312624022
trojan horse effect: phagocyte-mediated streptococcus iniae infection of fish.the salmonid macrophage-like cell line rts-11 and purified trout pronephros phagocytes were used to analyze in vitro entry and survival of two streptococcus iniae serotypes. efficient invasion by s. iniae occurred in both cells, but only the type ii strain persisted in pronephros phagocytes for at least 48 h. ex vivo models of opsonin-dependent phagocytosis by pronephros phagocytes demonstrated increased phagocytosis efficacy. analysis of phagocytes collected from diseased fish demonstrated that ...200312704100
combination effects of cephalexin and gentamicin on edwardsiella tarda and streptococcus iniae.the objective of this study was to determine the in vitro activity of cephalexin-gentamicin combination by a microbroth chequerboard technique against clinical isolates of edwardsiella tarda and streptococcus iniae. gentamicin was shown more susceptible than cephalexin against both bacteria. the effect of cephalexin-gentamicin combination against both bacteria represented additive interaction. the combination even showed synergic interaction (22%) against e. tarda, with a fic index of <0.5 as a ...200312842330
emerging pathologies in aquaculture: effects on production and food safety.infectious diseases represent a limiting factor for the further development of italian aquaculture. the recent introduction and spreading of new pathogens, along with the global climatic change, has contributed to a considerable decrease in trout production. emerging pathologies in rainbow trout culture include viral diseases, e.g. infectious haematopoietic necrosis (ihn), bacterial diseases, such as lactococcosis and visceral flavobacteriosis, and parasitical diseases, e.g. proliferative kidney ...200314535454
a third report of "golf ball disease" in an amazon river dolphin (inia geoffrensis) associated with streptococcus iniae.an amazon river dolphin (inia geoffrensis) developed a dermatologic syndrome characterized by the occurrence of slow-growing, nodular, s.c. abscesses. initial biopsies, cultures, and cytologic analysis of needle aspirates from the abscesses indicated steatitis with probable secondary, gram-negative bacterial infection. treatment with dietary vitamin e supplement and broad-spectrum antibiotics yielded minimal improvement. subsequent cultures revealed streptococcus iniae in addition to several gra ...200314582795
multiplex pcr assay for detection of bacterial pathogens associated with warm-water streptococcosis in fish.a multiplex pcr-based method was designed for the simultaneous detection of the main pathogens involved in warm-water streptococcosis in fish (streptococcus iniae, streptococcus difficilis, streptococcus parauberis, and lactococcus garvieae). each of the four pairs of oligonucleotide primers exclusively amplified the targeted gene of the specific microorganism. the sensitivity of the multiplex pcr using purified dna was 25 pg for s. iniae, 12.5 pg for s. difficilis, 50 pg for s. parauberis, and ...200415128589
zebrafish as a model host for streptococcal pathogenesis.streptococcal pathogens continue to evade concerted efforts to determine clear-cut virulence mechanisms, although numerous genes have been implicated in pathogenesis. a single species can infect a diversity of tissues, suggesting the expression of specific virulence factors based on the local tissue environment or stage of infection. in an effort to identify the interactions that occur between the host and pathogen that lead to activation of virulence mechanisms and contribute to specific strept ...200415158689
development of a pcr assay for streptococcus iniae based on the lactate oxidase (lcto) gene with potential diagnostic value.streptococcus iniae is a well-known pathogen of both fish and humans that is difficult to identify by conventional biochemical tests. a pcr assay based on the lactate oxidase (lcto) gene of s. iniae was developed for the rapid and specific detection and identification of this pathogen from different sources. the pcr assay had a detection limit of 62-31 cells, and 25 pg of dna per pcr reaction mixture. the pcr was also effective in detecting the bacterium from inoculated tissue homogenates, sugge ...200415172693
in vitro effect of a buffered chelating agent and neomycin or oxytetracycline on bacteria associated with diseases of fish.the antimicrobial agents used to treat bacterial fish diseases are archaic, and their uses may result in the emergence of drug-resistant bacterial strains. this study evaluated the in vitro antimicrobial activity of combinations of tricide and neomycin or oxytetracycline on common disease-causing bacteria of fish and its possible use as an alternative treatment of these diseases. tricide solutions containing of 8 mm united states pharmacopeia (usp) disodium ethylenediaminetetraacetate dehydrate ...200415264722
efficacy of streptococcus agalactiae (group b) vaccine in tilapia (oreochromis niloticus) by intraperitoneal and bath immersion administration.we evaluated the effectiveness of a streptococcus agalactiae vaccine in tilapia (oreochromis niloticus) for prevention of streptococcal disease. the vaccine was prepared from formalin-killed cells and concentrated extracellular products (greater than 3 kda) of a single isolate of s. agalactiae (ars-ku-mu-11b). intraperitoneal (ip) and bath immersion (bi) vaccine trials were conducted at two temperatures, 32 and 26 degrees c, and mean fish weights, 5 and 30 g. control tilapia were injected with t ...200415315858
streptococcus iniae discitis in singapore. 200415503411
bass hepcidin synthesis, solution structure, antimicrobial activities and synergism, and in vivo hepatic response to bacterial infections.bass hepcidin was purified from the gill of hybrid striped bass (morone chrysops x morone saxatilis) based on antimicrobial activity against escherichia coli. this 21-amino acid peptide has 8 cysteines engaged in 4 disulfide bonds and is very similar to human hepcidin, an antimicrobial peptide with iron regulatory properties. to gain insight into potential role(s) of bass hepcidin in innate immunity in fish, we synthesized the peptide, characterized its antimicrobial activities in vitro, determi ...200515546886
streptococcus iniae type ii infections in rainbow trout oncorhynchus mykiss.clinical and pathological findings (anorexia, hemorrhage, lethargy, loss of orientation and exophthalmia) indicated that streptococcus iniae type ii is responsible for a fatal disease in rainbow trout. histopathological findings revealed that s. iniae type ii produces a systemic disease, including a diffuse necrotizing myositis. the distribution of viable bacteria in infected tissues substantiated the pathological findings, confirming that s. iniae type ii is responsible for a generalized septic ...200415648844
large-scale screen highlights the importance of capsule for virulence in the zoonotic pathogen streptococcus iniae.zoonotic pathogens have the unique ability to cross the species barrier, causing disease in both humans and specific animal hosts. streptococcus iniae is a zoonotic pathogen of both fish and humans, and the clinical presentations of s. iniae infections in fish and humans are very similar to those caused by various human-specific streptococcal pathogens. virulence mechanisms required for infection by this pathogen of either host have yet to be determined. using the previously reported zebrafish i ...200515664934
identification and characterization of sporadic isolates of streptococcus iniae isolated from humans.seven reference strains and seven clinical isolates of streptococcus iniae, submitted to the centers for disease control and prevention streptococcus reference laboratory between 2001 and 2004, were successfully identified by a conventional identification system. the seven randomly submitted clinical isolates were sensitive to beta-lactams, macrolides, quinolones, and vancomycin. two of the seven clinical isolates were resistant to tetracycline. all seven strains grew well and multiplied in a ph ...200515695711
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
a vaccination and challenge model using calcein marked fish.a vaccination and challenge cohabitation model was established and evaluated using nile tilapia (oreochromis niloticus), the fluorescent chromophore calcein, and a streptococcus iniae vaccine. tilapia were non-invasively calcein marked, sham-vaccinated (cmsv) and cohabited with non-marked sham-vaccinated (nmsv) or non-marked s. iniae vaccinates (nmv) as a single unit. after 30 d, the cohabitants were challenged with a virulent isolate of s. iniae by intraperitoneal (ip) injection and the cumulat ...200616018935
streptococcus iniae phosphoglucomutase is a virulence factor and a target for vaccine development.streptococcus iniae represents a major health and economic problem in fish species worldwide. random tn917 mutagenesis and high-throughput screening in a hybrid striped bass (hsb) model of meningoencephalitis identified attenuated s. iniae mutants. the tn917 insertion in one mutant disrupted an s. iniae homologue of a phosphoglucomutase (pgm) gene. electron microscopy revealed a decrease in capsule thickness and cell wall rigidity, with deltapgm mutant cells reaching sizes approximately 3-fold l ...200516177373
response and function of cutaneous mucosal and serum antibodies in barramundi (lates calcarifer) acclimated in seawater and freshwater.mucosal and serum antibody responses were studied in sibling barramundi (lates calcarifer) acclimated in either seawater or freshwater following vaccination by intraperitoneal injection or direct immersion in an inactivated streptococcus iniae vaccine. as expected, route of vaccination had a marked effect on immune response, with direct immersion resulting in low serum antibody levels against s. iniae by elisa detected 21 days post vaccination at 26 degrees c, whilst a significant response was d ...200616337812
clinical isolates of streptococcus iniae from asia are more mucoid and beta-hemolytic than those from north america.streptococcus iniae, a widely distributed fish pathogen, is known to cause rare cases of human infection. we describe 2 cases of invasive s. iniae infection, one with septic arthritis complicating chronic gout and the other with bacteremic cellulitis. both patients were chinese and have been regularly handling fresh fish for cooking. both isolates were unidentified or misidentified by 3 commercially available identification system and were only identified by 16s rrna gene sequencing. when compar ...200616427243
streptococcus iniae capsule impairs phagocytic clearance and contributes to virulence in fish.surface capsular polysaccharides play a critical role in protecting several pathogenic microbes against innate host defenses during infection. little is known about virulence mechanisms of the fish pathogen streptococcus iniae, though indirect evidence suggests that capsule could represent an important factor. the putative s. iniae capsule operon contains a homologue of the cpsd gene, which is required for capsule polymerization and export in group b streptococcus and streptococcus pneumoniae. t ...200717098893
the immune response of tilapia oreochromis mossambicus and its susceptibility to streptococcus iniae under stress in low and high temperatures.mozambique tilapia oreochromis mossambicus acclimated to 27 degrees c were then held at 19, 23, 27 (control), 31 and 35 degrees c, and were examined for non-specific cellular and humoral responses after 12-96 h. total leucocyte count decreased significantly when fish were transferred to 19 and 23 degrees c after 48 and 96 h, and when transferred to 35 degrees c over 12-96 h, respectively. respiratory burst decreased significantly when fish were transferred to 19, 31 and 35 degrees c over 24-96 h ...200717132470
analysis of the polysaccharide capsule of the systemic pathogen streptococcus iniae and its implications in virulence.systemic pathogens have developed numerous strategies for evading the defenses of the host, permitting dissemination and multiplication in various tissues. one means of survival in the host, particularly in the bloodstream, has been attributed to the ability to avoid phagocytosis via capsular polysaccharide. to further define the virulence capacity of streptococcus iniae, a zoonotic pathogen with the ability to cause severe systemic disease in both fish and humans, we performed an analysis of th ...200717194809
the macrophage chemotactic activity of streptococcus agalactiae and streptococcus iniae extracellular products (ecp).the ability of streptococcus agalactiae and streptococcus iniae to attract macrophages of nile tilapia (oreochromis niloticus) was investigated. the extracellular products (ecp) from s. agalactiae and s. iniae were tested in vitro for macrophage chemotaxis using blind-well chambers. the macrophages were obtained from the peritoneal cavity 4-5 days after intraperitoneal injection of squalene. both macrophage chemotactic and chemokinetic activities were demonstrated using the s. agalactiae ecp. ho ...200717212985
selective agars for the isolation of streptococcus iniae from japanese flounder, paralichthys olivaceus, and its cultural environment.two kinds of selective agar were developed for the isolation of streptococcus iniae, the causal agent of streptococcosis, from japanese flounder (paralichthys olivaceus) and from culture tanks in flounder farms. the selective agars were heart infusion agar with added thallium acetate and oxlinic acid (taoa), and colistin sulphate and oxolinic acid (csoa). for samples containing various bacterial flora, selective agars were supplemented with defibrinated horse blood in order to distinguish beta-h ...199910347871
evaluation of the link between gyrodactylosis and streptococcosis of nile tilapia, oreochromis niloticus (l.).streptococcus iniae and gyrodactylus niloticus are two common pathogens of cultured nile tilapia, oreochromis niloticus. we studied concurrent infection of tilapia by g. niloticus and s. iniae and evaluated whether parasitism in tilapia with gyrodactylus increased susceptibility and mortality following immersion infection with s. iniae. results showed that death mainly occurred in fish with g. niloticus and challenged with s. iniae (g-s group). the accumulative mortality (42.2%) was significantl ...200717394525
streptococcus iniae: an aquatic pathogen of global veterinary significance and a challenging candidate for reliable vaccination.streptococcus iniae has become one the most serious aquatic pathogens in the last decade causing high losses in farmed marine and freshwater finfish in warmer regions. although first identified in 1976 from a captive amazon freshwater dolphin, from which it derives its name, disease outbreaks had most likely been occurring for several decades in marine aquaculture in japan. s. iniae is globally distributed throughout warm water finfish aquaculture. in common with other encapsulated beta-haemolyt ...200717418985
capsule expression regulated by a two-component signal transduction system in streptococcus iniae.streptococcus iniae causes disease in fish and humans and the presence of capsule is associated with virulence. tn917 transposon mutagenesis was performed to identify capsule-associated genes and a mutant was isolated, with an insertion in a genetic locus encoding a two-component signal transduction system (tcs), which we termed sivs/r. sivs and sivr encode a 506-amino-acid (aa) putative histidine kinase and a 223-aa putative response regulator, respectively. in order to investigate the role of ...200717537179
cloning, expression and antimicrobial activity of crustinpm1, a major isoform of crustin, from the black tiger shrimp penaeus monodon.crustin antibacterial homologues, containing a whey acidic protein (wap) domain, have been identified from the haemocyte library of the black tiger shrimp, penaeus monodon. sequence analysis of these cdnas indicates the presence of several isoforms of crustin in p. monodon. crustinpm1, the most abundant isoform, contains an open reading frame of 435bp encoding a precursor of 145 amino acids that comprises 17 amino acid signal peptides and 128 amino acid mature peptides. the peptides contain a gl ...200817573111
strain characteristics of streptococcus iniae isolated from tilapia species in vancouver, british columbia. 19989844254
streptococcus iniae beta-hemolysin streptolysin s is a virulence factor in fish infection.streptococcus iniae is a leading pathogen of intensive aquaculture operations worldwide, although understanding of virulence mechanisms of this pathogen in fish is lacking. s. iniae possesses a homolog of streptolysin s (sls), a secreted, pore-forming cytotoxin that is a proven virulence factor in the human pathogen s. pyogenes. here we used allelic exchange mutagenesis of the structural gene for the s. iniae sls precursor (saga) to examine the role of sls in s. iniae pathogenicity using in vitr ...200717718161
invasive infection with streptococcus iniae in taiwan.streptococcus iniae, a common fish pathogen, rarely infects humans. in this report, a case of invasive s. iniae infection in a 51-year-old woman with diabetes mellitus and hepatitis c-related liver cirrhosis is described. the isolate was identified by 16s rdna sequencing. the patient recovered after 1 week of treatment with ampicillin.200717761491
the development of probiotics for the control of multiple bacterial diseases of rainbow trout, oncorhynchus mykiss (walbaum).jb-1 and gc2, which were equated with bacillus sp. and aeromonas sobria respectively, were recovered from the digestive tract of rainbow trout, oncorhynchus mykiss and ghost carp, cyprinus sp. respectively, and demonstrated effectiveness as probiotics for the control of infections caused by aeromonas salmonicida, lactococcus garvieae, streptococcus iniae, vibrio anguillarum, vibrio ordalii and yersinia ruckeri. when administered to rainbow trout (average weight = 12 g) for 14 days in feed dosed ...200717850573
updating the importance of lactic acid bacteria in fish farming: natural occurrence and probiotic treatments.many recent papers have deepened the state of knowledge about lactic acid bacteria (lab) in fish gut. in spite of high variability in fish microbiota, lab are sometimes abundant in the intestine, notably in freshwater fish. several strains of streptococcus are pathogenic to fish. streptococcus iniae and lactococcus garvieae are major fish pathogens, against which commercial vaccines are available. fortunately, most lab are harmless, and some strains have been reported for beneficial effects on f ...200817957117
the two-component system sivs/r regulates virulence in streptococcus iniae.streptococcus iniae causes invasive disease and death in fish, and to a lesser extent, sporadic cases of soft-tissue infections in humans. a two-component system termed sivs/r, which regulates capsule expression, was previously identified and characterized. in this study, it is shown that a sivs/r deletion-insertion mutant, termed 9117deltasiv, causes transient bacteremia and reduced virulence compared with the parent strain when tested in a murine model of bacteremic infection. furthermore, rea ...200717991014
transcytosis of streptococcus iniae through skin epithelial barriers: an in vitro study.by constructing a biological model based on in vitro culture of polarized rainbow trout primary skin epithelial cell monolayers, the series of early events that precede streptococcus iniae infection, particularly colonization and translocation through external barriers, were analyzed. streptococcus iniae promptly invades skin epithelial cells, but the rapid decline of viable intracellular bacteria points out the limited capability of intracellular survival for this bacterium. translocation assay ...200718031346
restriction fragment length polymorphisms of 16s rdna and of whole rrna genes (ribotyping) of streptococcus iniae strains from the united states and israel.streptococcus iniae (junior synonym s. shiloi) isolated from tilapia and trout in israel and in the united states were subtyped by restriction length polymorphism (rflp) based on pcr amplified 16s rdna and by ribotyping. 16s rdna rflp discriminated between s. iniae and other fish pathogens but not between s. iniae strains. hindiii and ecori ribotypes of s. iniae discriminated american from israeli strains rejecting the possibility of an epidemiological link between s. iniae infections in the two ...19979228748
genetic variability amongst streptococcus iniae isolates from australia. 200818353022
strain-associated virulence factors of streptococcus iniae in hybrid-striped bass.streptococcus iniae is a major fish pathogen producing invasive infections that result in economic losses in aquaculture. development of in vitro models of s. iniae virulence may provide insight to the pathogenesis of infection in vivo. three s. iniae strains (k288, 94-426, and 29178) were tested for virulence in a hybrid-striped bass (hsb) model using intraperitoneal injection. s. iniae strains k288 and 94-426 caused high levels of mortality in hsb (lethal dose 2x10(5)cfu) while strain 29178 wa ...200818406547
identification and molecular characterisation of a fibrinogen binding protein from streptococcus iniae.binding of serum components by surface m-related proteins, encoded by the emm genes, in streptococci constitutes a major virulence factor in this important group of organisms. the present study demonstrates fibrinogen binding by s. iniae, a lancefield non-typeable pathogen causing devastating fish losses in the aquaculture industry and an opportunistic pathogen of humans, and identifies the proteins involved and their encoding genes.200818430254
identification and molecular characterization of two hepcidin genes from black rockfish (sebastes schlegelii).antimicrobial peptides (amps) are important mediators of the immune response against bacteria and cysteine-rich peptide hepcidin is a 20-26 residues member with functions in iron regulation and antimicrobial activity. here, we have identified two different types of hepcidin cdna from the black rockfish, sebastes schlegelii, by est analysis. both hepcidin genes (hepcidin i and ii) consist of two introns and three exons that encode a prepropeptide (88 amino acids). a tata box and several consensus ...200818496731
distribution of marine birnavirus in cultured olive flounder paralichthys olivaceus in korea.surveys of marine birnavirus (mabv) were undertaken in cultured olive flounder paralichthys olivaceus from the south and west coastal areas and jeju in korea during the period january 1999 to april 2007. mabv was detected in all seasons from the fry, juveniles and adult fish from the areas examined. evident cytopathic effects of the virus including rounding and cell lysis were observed in chinook salmon embryo (chse-214) and rainbow trout gonad (rtg-2) cells, but not in fathead minnow (fhm) and ...200818604495
streptococcus iniae m-like protein contributes to virulence in fish and is a target for live attenuated vaccine development.streptococcus iniae is a significant pathogen in finfish aquaculture, though knowledge of virulence determinants is lacking. through pyrosequencing of the s. iniae genome we have identified two gene homologues to classical surface-anchored streptococcal virulence factors: m-like protein (sima) and c5a peptidase (scpi).200818665241
differential modulations of two glyceraldehyde 3-phosphate dehydrogenase mrnas in response to bacterial and viral challenges in a marine teleost oplegnathus fasciatus (perciformes).glyceraldehyde 3-phosphate dehydrogenase (gapdh) has been recognized as an invariant internal control for various gene expression studies due to its classical housekeeping role in the glycolytic metabolism. however recently, this enzyme has been proven to be a multifunctional protein involved in diverse non-glycolytic activities. in the present study, two paralogue isoforms of gapdh mrnas were characterized from a marine teleost species, rockbream (oplegnathus fasciatus; perciformes) and their t ...200818692141
the il-8 protease spycep/scpc of group a streptococcus promotes resistance to neutrophil killing.interleukin-8 (il-8) promotes neutrophil-mediated host defense through its chemoattractant and immunostimulatory activities. the group a streptococcus (gas) protease spycep (also called scpc) cleaves il-8, and spycep expression is strongly upregulated in vivo in the m1t1 gas strains associated with life-threatening systemic disease including necrotizing fasciitis. coupling allelic replacement with heterologous gene expression, we show that spycep is necessary and sufficient for il-8 degradation. ...200818692776
evolution of the inflammatory response in vertebrates: fish tnf-alpha is a powerful activator of endothelial cells but hardly activates phagocytes.tnf-alpha is conserved in all vertebrate classes and has been identified in all taxonomic groups of teleost fish. however, its biological activities and its role in infection are largely unknown. using two complementary fish models, gilthead seabream and zebrafish, we report here that the main proinflammatory effects of fish tnf-alpha are mediated through the activation of endothelial cells. thus, tnf-alpha promotes the expression of e-selectin and different cc and cxc chemokines in endothelial ...200818802111
emergence of novel streptococcus iniae exopolysaccharide-producing strains following vaccination with nonproducing strains.streptococcus iniae is a major pathogen of fish, producing fatal disease among fish species living in very diverse environments. recently, reoccurrences of disease outbreaks were recorded in rainbow trout (oncorhynchus mykiss, walbaum) farms where the entire fish population was routinely vaccinated. new strains are distinguished from previous strains by their ability to produce large amounts of extracellular polysaccharide that is released into the medium. present findings indicate that the extr ...200818806000
identification and genetic characterization of streptococcus iniae strains isolated from diseased fish in china. 200818840139
antibiotic susceptibility and resistance of streptococcus iniae and streptococcus parauberis isolated from olive flounder (paralichthys olivaceus).the rates of antibiotic susceptibility and resistance were investigated in streptococcus iniae and streptococcus parauberis isolates obtained from diseased olive flounders (paralichthys olivaceus) collected from fish farms in jeju island, korea. isolates of s. iniae (n=65) were susceptible to cefotaxime, erythromycin, ofloxacin, penicillin, tetracycline and vancomycin, as demonstrated by the minimum inhibitory concentration (mic) test. isolates of s. parauberis (n=86) were highly resistant to er ...200919019569
identification of novel genes in japanese flounder (paralichthys olivaceus) head kidney up-regulated after vaccination with streptococcus iniae formalin-killed cells.streptococcosis caused by streptococcus iniae, a gram-positive bacterium, is one of the diseases often found in the culture of japanese flounder (paralichthys olivaceus). inactivated bacterial-whole cells of s. iniae have been used as a prophylactic treatment to prevent the disease. to understand the molecular mechanisms involved in activation of the fish immune system upon formalin-killed cell (fkc) treatment, we have investigated the gene transcription profile of japanese flounder head kidney ...200919038556
growth differentiation factor 15, a novel acute phase response gene in japanese flounder, paralichthys olivaceus.the acute phase response, an important aspect of innate immunity, leads to the production of acute phase proteins (apps) in the liver which would consequently help restore homeostasis to the body. here, we identified a novel cytokine, growth differentiation factor 15 (gdf15) from japanese flounder. three out of the 384 est sequences derived from liver of japanese flounder treated with formalin-killed edwardsiella tarda showed significant homology with gdf of various species. after obtaining the ...200919059342
modelling and predicting the effect of temperature, water activity and ph on growth of streptococcus iniae in tilapia.to evaluate and model the growth of streptococcus iniae affect by temperatures (10-45 degrees c), water activity (a(w); 0.995-0.957), and ph (5-8).200819120642
experimental streptococcal meningo-encephalitis in cultured fish.in 1984 a disease of fish appeared in israel which spread rapidly in cultured fishponds. the disease affected tilapia (oreochromis aura x oreochromis nilotica hybrids) and trout (oncorhynchus mykiss). common carp (cyprinus carpus), although reared in community with tilapia were not susceptible to the disease. various species of ornamental cyprinids and cichlids were also affected. morbidity was high and mortality ranged between 50% (in trout) and 30% (in tilapia). clinical and pathological findi ...19957716882
partial two-dimensional gel electrophoresis (2-de) maps of streptococcus iniae atcc29178 and lactococcus garvieae kg9408.to examine the proteomes of 2 important causative agents of fish streptococcosis, streptococcus iniae atcc29178 and lactococcus garvieae kg9408, we used 2-dimensional gel electrophoresis (2-de) followed by mass spectrometry to generate 2-de maps of these type strains. silver-stained 2-de gels of s. iniae atcc29178 and l. garvieae kg9408 revealed approximately 320 and 300 spots, respectively, and immobilized ph gradient strips (13 cm, ph 4 to 7) revealed that the majority of the detected spots we ...200616875393
phenotypic characteristics of streptococcus iniae and streptococcus parauberis isolated from olive flounder (paralichthys olivaceus).the etiological agents of streptococcosis were isolated from diseased olive flounder collected on the jeju island of korea. a total of 151 bacterial isolates were collected between 2003 and 2006. the isolates were examined using various phenotypic and proteomic analyses, including sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page), immunoblotting, and glycoprotein assays. in addition, isolates were grown on blood agar to assess hemolytic activity, and biochemical assays were pe ...200919278524
streptococcal cellulitis following preparation of fresh raw seafood.we describe three zoonotic streptococcal soft tissue infections resulting from fresh seafood contact. one was a localized thumb infection with streptococcus iniae in an immunocompetent healthy young male resulting from a puncture wound from a crab pincer. the other two were cases of ascending upper limb cellulitis associated with bacteraemia in mastectomy patients. one of these infections was caused by s. iniae while the other was caused by streptococcus dysgalactiae subsp. dysgalactiae, a speci ...200919309483
adult zebrafish model of streptococcal infection.streptococcal pathogens cause a wide array of clinical syndromes in humans, including invasive systemic infections resulting in high mortality rates. many of these pathogens are human specific, and therefore difficult to analyze in vivo using typical animal models, as these models rarely replicate what is observed in human infections. this unit describes the use of the zebrafish (danio rerio) as an animal model for streptococcal infection to analyze multiple disease states. this model closely mi ...200919412913
characterization of probiotic carnobacteria isolated from rainbow trout (oncorhynchus mykiss) intestine.to characterize two probiotic carnobacterial isolates, carnobacterium maltaromaticum (b26) and c. divergens (b33), derived from rainbow trout (oncorhynchus mykiss) intestine.200819552776
dietary oligonucleotides from yeast rna influence immune responses and resistance of hybrid striped bass (morone chrysops x morone saxatilis) to streptococcus iniae infection.three feeding trials were conducted to evaluate potential immunomodulatory effects of nucleotides in the diet of hybrid striped bass. a basal diet was formulated from menhaden fish meal to contain 40% crude protein and 10% lipid. an oligonucleotide product (ascogen p) from brewer's yeast was added to the basal formulation at the manufacturer's recommended rate of 0.5% to produce the experimental diet. each diet was fed to four replicate groups of juvenile hybrid striped bass for seven or eight w ...200415110330
lactococcus garvieae in wild red sea wrasse coris aygula (labridae).lactococcus garvieae infection in wild wrasse coris aygula is reported, and the serological and molecular characteristics of the isolate are described. this is the first evidence of the presence of this pathogen in the red sea, and it follows the recent diagnosis of mycobacterium marinum and streptococcus iniae in wild fish from the same region. whether all 3 pathogens are strains endemic to the red sea, or recent introductions into the region, remains to be determined, but their appearance over ...200314667040
molecular cloning and characterization of lps-binding protein/bactericidal permeability-increasing protein (lbp/bpi) from olive flounder, paralichthys olivaceus.a lipopolysaccharide (lps)-binding protein/bactericidal permeability-increasing protein (lbp/bpi) homolog was isolated from peripheral blood leukocytes cdna library of olive flounder paralichthys olivaceus. the isolated lbp/bpi cdna is 2806bp in length with a 1419bp open reading frame (orf) that encodes a protein of 472 amino acid residues. the lps-binding domain is well conserved in the n-terminal barrel, showing high sequence identities with other teleost lbp/bpi as well as those of mammals. r ...201019698997
streptococcus iniae: serological differences, presence of capsule and resistance to immune serum killing.the biochemical profiles, presence of capsule, outer membrane protein profiles and serological interactions of isolates of streptococcus iniae obtained from different geographical and fish host origins were examined. the isolates had very similar biochemical profiles using api 20 strep but varied as to whether they were arginine dihydrolase-negative, -positive or -intermediate (ad-ve, ad+ve, ad+/-ve, respectively). representatives of each ad type were compared in subsequent experiments. all type ...200312691195
the novel polysaccharide deacetylase homologue pdi contributes to virulence of the aquatic pathogen streptococcus iniae.the aquatic zoonotic pathogen streptococcus iniae represents a threat to the worldwide aquaculture industry and poses a risk to humans who handle raw fish. because little is known about the mechanisms of s. iniae pathogenesis or virulence factors, we established a high-throughput system combining whole-genome pyrosequencing and transposon mutagenesis that allowed us to identify virulence proteins, including pdi, the polysaccharide deacetylase of s. iniae, that we describe here. using bioinformat ...201019762441
activation of nonspecific cytotoxic cells (ncc) with synthetic oligodeoxynucleotides and bacterial genomic dna: binding, specificity and identification of unique immunostimulatory motifs.we have analyzed the effects of synthetic oligodeoxynucleotides (sodns) and bacterial dna (bdna) on the in vitro activation of ncc. teleost ncc recognition of dna appeared to differ from that which occurs in higher vertebrates. ncc contain at least two different receptor specificities for dna. both oligodeoxyguanosine 20-mers (dg20) and 5'-tgctgcttgtgcttgtgctt-3' (4gc-2t) bound specifically to ncc. the existence of different receptor specificities was indicated by reciprocal cold target inhibiti ...200211755675
towards control of streptococcus iniae.streptococcus iniae is an emerging zoonotic pathogen; such infections generally occur through injuries associated with preparing whole fresh fish for cooking. those infected to date have been of asian descent, are usually elderly (average age 68 years), and have had >/=1 underlying conditions that may predispose them to infection. studies of the foundations of growth characteristics of s. iniae and its interactions with piscine host cells have recently been complemented by molecular studies. adv ...200919961667
recovery of streptococcus iniae from diseased fish previously vaccinated with a streptococcus vaccine.streptococcus iniae was recovered from diseased rainbow trout (oncorhynchus mykiss, walbaum) previously vaccinated against streptococcosis. pcr and serological methods indicate the presence of a new serotype in the diseased fish.200111472962
dried leaves of rosmarinus officinalis as a treatment for streptococcosis in tilapia.dietary application of dried rosmarinus officinalis (rosemary) leaves as a treatment for streptococcal infection was studied in tilapia, oreochromis sp. feeding with dried rosemary leaves significantly reduced mortality following infection with streptococcus iniae: 44% mortality in the group fed 8% rosemary, similar to oxytetracycline treatment (43% mortality), and significantly lower than the control (65%). dietary administration of 16% rosemary significantly reduced mortality because of strept ...201020158579
a pivotal role for the streptococcus iniae extracellular polysaccharide in triggering proinflammatory cytokines transcription and inducing death in rainbow trout.streptococcus iniae is a major pathogen of fish, causing considerable economic losses in israel, the united states and the far east. containment of mortalities through vaccination was recently compromised due to the emergence of novel vaccine-escape strains that are distinguished from previous strains by their ability to produce large amounts of extracellular polysaccharide (eps) that is released to the medium. in vitro and in vivo data now indicate that the eps is a major virulence factor, capa ...201020199577
cloning and analysis of the l-lactate utilization genes from streptococcus iniae.the presence of lactate oxidase was examined in eight streptococcus species and some related species of bacteria. a clone (pgr002) was isolated from a genomic library of streptococcus iniae generated in escherichia coli, containing a dna fragment spanning two genes designated lcto and lctp. we show that these genes are likely to be involved in the l-lactic acid aerobic metabolism of this organism. this dna fragment has been sequenced and characterized. a comparison of the deduced amino acid sequ ...199910508058
identification and molecular analysis of a novel c-type lectin from scophthalmus maximus.c-type lectins are calcium-dependent carbohydrate-binding proteins that play important roles in innate immunity. in this study, a c-type lectin homologue (smlec1) was identified from turbot (scophthalmus maximus) and analyzed at expression and functional levels. the open reading frame of smlec1 is 504 bp, with a 5'-untranslated region (utr) of 101 bp and a 3'-utr of 164 bp. the deduced amino acid sequence of smlec1 shares 34%-38% overall identities with the c-type lectins of several fish species ...201020226863
red drum sciaenops ocellatus mortalities associated with streptococcus iniae infection.we isolated for the first time streptococcus iniae strains associated with diseased marine fish. diseased red drum sciaenops ocellatus were lethargic, and presented external signs (exophthalmia and loss of orientation) resembling those of freshwater fish infected by s. iniae. skin lesions, extending to a necrotizing myositis, were typical of s. iniae infection of red drum. histopathological findings indicate that s. iniae infection in red drum produces a chronic disease with systemic involvement ...199910399040
construction and analysis of an experimental streptococcus iniae dna vaccine.streptococcus iniae is a severe aquaculture pathogen that can also infect humans and animal. a putative secretory antigen, sia10, was identified from a pathogenic s. iniae strain by in vivo-induced antigen technology. using turbot as an animal model, the immunoprotective effect of sia10 was examined as a dna vaccine in the form of plasmid psia10, which expresses sia10 under the cytomegalovirus immediate-early promoter. in fish vaccinated with psia10, transcription of sia10 was detected in muscle ...201020394724
evaluation of streptococcus iniae killed bacterin and live attenuated vaccines in hybrid striped bass through injection and bath immersion.streptococcus iniae poses a serious threat to finfish aquaculture operations worldwide. stringent regulatory standards limit the use of antibiotics to treat s. iniae infections; improved vaccination strategies are thus of great interest. we investigated the potential for efficient, non-injectable batch vaccination via the use of live attenuated vaccines. three attenuated s. iniae strains with genetic mutations eliminating the production of virulence factors--capsular polysaccharide (delta cpsd), ...201020402229
an outbreak of streptococcus iniae in barramundi (lates calcarifera) in freshwater cage culture. 200617092328
a commercial rapid optical immunoassay detects streptococcus agalactiae from aquatic cultures and clinical specimens.the biostar strep b optical immunoassay (strep b oia) (biostar oia strep b assay kit; biostar incorporation, louisville, co, usa), commonly used for diagnosis of human maternal group b streptococcus (gbs) colonization, was evaluated for its diagnostic and analytical sensitivity and specificity to aquatic animal gbs isolates, cross-reactivity, and diagnosis and recovery of gbs directly from clinically- infected fish swabs. strep b oia identified 25 known fish and dolphin gbs isolates. thirteen no ...201020430538
identification and molecular analysis of a stress-inducible hsp70 from sciaenops ocellatus.hsp70 proteins are a family of molecular chaperones that are involved in many aspects of protein homeostasis. in this study, an hsp70 homologue (sohsp70) was identified from red drum sciaenops ocellatus and analyzed at molecular level. the open reading frame of sohsp70 is 1920 bp and intronless, with a 5'-untranslated region (utr) of 399 bp and a 3'-utr of 241 bp. the deduced amino acid sequence of sohsp70 shares 84-92% overall identities with the hsp70s of a number of fish species. in silico an ...201020541016
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