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Genome Announcements Feb 2016We sequenced the complete genome of the type strain of Aeromonas schubertii, ATCC 43700. The full genome sequence of A. schubertii ATCC 43700 is 4,356,858 bp, which...
We sequenced the complete genome of the type strain of Aeromonas schubertii, ATCC 43700. The full genome sequence of A. schubertii ATCC 43700 is 4,356,858 bp, which encodes 3,842 proteins and contains 110 predicted RNA genes.
PubMed: 26893413
DOI: 10.1128/genomeA.00012-16 -
Comparative Biochemistry and... 2021Mitogen-activated protein kinase/extracellular signal-regulated kinase kinase kinase 3 (MEKK3) is a serine/threonine protein kinase that acts as a key regulator and is...
MEKK3 in hybrid snakehead (Channa maculate ♀ ×Channa argus ♂): Molecular characterization and immune response to infection with Nocardia seriolae and Aeromonas schubertii.
Mitogen-activated protein kinase/extracellular signal-regulated kinase kinase kinase 3 (MEKK3) is a serine/threonine protein kinase that acts as a key regulator and is widely involved in various innate and acquired immune signaling pathways. In this study, we first cloned the complete open reading frame (ORF) of the MEKK3 gene (named CcMEKK3) in a hybrid snakehead (Channa maculate ♀ × Channa argus ♂). The full-length ORF of CcMEKK3 is 1851 bp, and encodes a putative protein of 616 amino acids containing a serine/threonine kinase catalytic (S-TKc) domain and a Phox and Bem1p (PB1) domain. A sequence alignment and phylogenetic tree analysis showed that CcMEKK3 is highly conserved relative to the MEKK3 proteins of other teleost species. CcMEKK3 was constitutively expressed in all the healthy hybrid snakehead tissues tested, with greatest expression in the immune tissues, such as the head kidney and spleen. The expression of CcMEKK3 was usually upregulated in the head kidney, spleen, and liver at different time points after infection with Nocardia seriolae or Aeromonas schubertii. Similarly, the dynamic expression levels of CcMEKK3 in head kidney leukocytes after stimulation revealed that CcMEKK3 was induced by LTA, LPS, and poly(I:C). In the subcellular localization analysis, CcMEKK3 was evenly distributed in the cytoplasm of HEK293T cells, and its overexpression significantly promoted the activities of NF-κB and AP-1. These results suggest that CcMEKK3 is involved in the immune defense against these two pathogens, and plays a crucial role in activating the NF-κB and MAPK signaling pathways.
Topics: Aeromonas; Animals; Fish Diseases; Fish Proteins; Fishes; Gram-Negative Bacterial Infections; Immunity, Innate; MAP Kinase Kinase Kinase 3; Nocardia; Nocardia Infections
PubMed: 34186154
DOI: 10.1016/j.cbpb.2021.110643 -
Journal of Fish Diseases Oct 2018A disease with white spots in internal organs of Nile tilapia occurred in Zhanjiang, southern China. Multiple, white nodules, 0.8-2.2 mm in diameter, were scattered...
A disease with white spots in internal organs of Nile tilapia occurred in Zhanjiang, southern China. Multiple, white nodules, 0.8-2.2 mm in diameter, were scattered throughout the liver, spleen and kidney of diseased fish. Signs of nodules reproduced after artificial infection with the isolated strain. Isolated bacteria were Gram-negative, facultative anaerobic, motile, short rod-shaped, with a length of 1.2-2.2 μm. Morphological and biochemical tests, as well as phylogenetic analysis, all strongly indicated that the isolate from tilapia is identical to Aeromonas schubertii (A. schubertii) which temporary named LF1708 strain. Antibiotic sensitivity assays showed the LF1708 is sensitive to 24 of 27 tested antibiotics. Pathogenicity test revealed that the isolate at the dose of 3.75 × 10 CFU/g killed 100% of experimental tilapia within 2 days and the dose of 1 × 10 CFU/g killed 100% of experimental zebrafish within 1 day. Histopathology of diseased tilapia infected with A. schubertii showed numerous necrotic lesions widely distributed in spleen, liver and kidney, and infiltration with a large number of bacteria. To our knowledge, this was the first report that associated A. schubertii with mortality in tilapia.
Topics: Aeromonas; Animals; Anti-Bacterial Agents; China; Cichlids; DNA Gyrase; DNA-Directed RNA Polymerases; Fish Diseases; Fisheries; Gram-Negative Bacterial Infections; Hydrogen-Ion Concentration; Kidney; Liver; Necrosis; Phylogeny; RNA, Ribosomal, 16S; Salinity; Spleen; Zebrafish
PubMed: 30039866
DOI: 10.1111/jfd.12848 -
Animals : An Open Access Journal From... Mar 2024is a pathogen that severely affects aquatic animals, including the snakehead, . Lytic bacteriophages have been recognized as effective alternatives to antibiotics for...
is a pathogen that severely affects aquatic animals, including the snakehead, . Lytic bacteriophages have been recognized as effective alternatives to antibiotics for controlling bacterial infections. However, there have been no reports of phages as far as we know. In this study, a lytic bacteriophage SD04, which could effectively infect , was isolated from pond water cultured with diseased snakehead. The SD04 phage formed small, round plaques on Petri dishes. Electron microscopy revealed a hexagonal head and a contractile tail. Based on its morphology, it may belong to the Myoviridae family. Two major protein bands with molecular weights of 50 and 38 kilodaltons were observed after the phage was subjected to SDS-PAGE. The phage showed a large average burst size, high specificity, and a broad host range. When stored at 4 °C, phage SD04 had high stability over 12 months and showed almost no variation within the first six months. All fish were healthy after both intraperitoneal injection and immersion administration of SD04, indicating the safety of the phage. After treatment with SD04, in both phage therapy groups and prevention groups showed high survival rates (i.e., 83.3 ± 3.3% and 100 ± 1.3%, respectively). Phage therapy inhibits bacterial growth in the liver, the target organ of the infected . The experimental results indicate the potential use of phage SD04 for preventing infection in .
PubMed: 38540055
DOI: 10.3390/ani14060957 -
FEMS Microbiology Letters Apr 1993Two oligonucleotide primers were used in a polymerase chain reaction-protocol to amplify a region (approx. 850 bp) of the 16S rRNA gene of Aeromonas schubertii and...
Two oligonucleotide primers were used in a polymerase chain reaction-protocol to amplify a region (approx. 850 bp) of the 16S rRNA gene of Aeromonas schubertii and Aeromonas jandaei. Hybridization of the polymerase chain reaction products to specific internal probes provided a highly specific method for the identification of these two species.
Topics: Aeromonas; Base Sequence; Blotting, Southern; DNA, Ribosomal; Molecular Sequence Data; Oligodeoxyribonucleotides; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Species Specificity
PubMed: 8486241
DOI: 10.1111/j.1574-6968.1993.tb06091.x -
Journal of Fish Diseases Jun 2012Pure bacterial cultures were isolated from diseased snakeheads, Channa maculata (Lacepède), suffering high mortality in a farm in Zhongshan, southern China. Three...
Pure bacterial cultures were isolated from diseased snakeheads, Channa maculata (Lacepède), suffering high mortality in a farm in Zhongshan, southern China. Three isolates, namely ZS20100725, ZS20100725-1 and ZS20100725-2, were identified as Aeromonas schubertii. All the isolates showed high 16S rRNA sequence similarities with A. schubertii. The isolates exhibited strong virulence to snakeheads in experimental challenges with LD(50) ranging between 1.4 × 10(4) and 6.4 × 10(6) CFU g(-1). Two of the isolates were positive for haemolysin, elastase, lipase and lecithinase by phenotypic determination, which was further confirmed by PCR amplification of the haemolysin and elastase genes. In sterile liquid medium, the best growth conditions of strain ZS20100725 were 30 °C, pH 7 and 0.5% salinity (w/v). Antibiotic susceptibility tests showed that strain ZS20100725 was susceptible to cefoxitin, cefoperazone and chloramphenicol. Furthermore, histopathology of diseased snakeheads infected with A. schubertii showed necrosis and congestion in liver, kidney and spleen and also damage to the cardiac muscle, intestine and gills.
Topics: Aeromonas; Animals; Base Sequence; Cefoperazone; Cefoxitin; China; Chloramphenicol; Computational Biology; DNA Primers; Fish Diseases; Hemolysin Proteins; Lethal Dose 50; Molecular Sequence Data; Pancreatic Elastase; Perciformes; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Species Specificity; Temperature; Virulence; Virulence Factors; Viscera
PubMed: 22524539
DOI: 10.1111/j.1365-2761.2012.01362.x -
Biotechnology Progress 2009Two SDS-resistant endochitinases, designated as ASCHI53 and ASCHI61, were isolated from Aeromonas schubertii in a soil sample from southern Taiwan. MALDI-TOF mass...
Two SDS-resistant endochitinases, designated as ASCHI53 and ASCHI61, were isolated from Aeromonas schubertii in a soil sample from southern Taiwan. MALDI-TOF mass measurement indicates the molecular weights of 53,527 for ASCHI53 and 61,202 for ASCHI61. N-terminal and internal amino acid sequences were obtained, and BLAST analysis of the sequences and MS/MS peptide sequencing showed that they were novel proteins. Degradation of chitin by these two endochitinases gave rise to hexameric chitin oligosaccharide, a compound known to have several potent biomedical functions. ASCHI53 and ASCHI61 retained, respectively, 65% and 75%, of their chitinase activity in the presence of 5% SDS and 100% of their activity in the presence of 10% beta-mercaptoethanol. These results demonstrate that they are SDS-resistant endochitinases and probably have a rigid structure.
Topics: Aeromonas; Bacterial Proteins; Chitinases; Enzyme Activation; Sodium Dodecyl Sulfate; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Tandem Mass Spectrometry
PubMed: 19197977
DOI: 10.1002/btpr.100 -
Journal of Fish Diseases May 2012An epizootic in snakehead fish, Ophiocephalus argus, in earthen ponds in Xianning, Hubei Province, central China, from June to August 2009 was found to be caused by...
An epizootic in snakehead fish, Ophiocephalus argus, in earthen ponds in Xianning, Hubei Province, central China, from June to August 2009 was found to be caused by Aeromonas schubertii. The cumulative mortality within 40 days was 45%, and the diseased fish were 18 months old and 35-45 cm in length. Multiple, ivory-white, firm nodules, 0.5-1 mm in diameter, were scattered throughout the kidney. Blood clots, 3-5 mm in diameter, were found in the liver. This is a disease frequently found in cultured snakehead throughout China. Isolated bacteria were Gram negative, facultatively anaerobic, motile, short rod-shaped, with a length of 0.3-1.0 μm. Morphological and biochemical tests, as well as phylogenetic analysis derived from 16S rRNA, gyrB, rpoD and dnaJ gene sequencing all strongly indicated that these snakehead isolates are identical to A. schubertii. In addition, the isolates possessed two plasmids: 5.0 kb and 10.0 kb. Antibiotic sensitivity testing of the isolates was carried out by the standard Kirby-Bauer disc diffusion method. Experimental infection assays were conducted, and pathogenicity (by intraperitoneal injection) was demonstrated in snakehead fingerlings and zebrafish, Brachydanio rerio (Hamilton).
Topics: Aeromonas; Animals; Anti-Infective Agents; China; Fish Diseases; Fisheries; Fresh Water; Genes, Bacterial; Gram-Negative Bacterial Infections; Molecular Sequence Data; Perciformes; Phylogeny; RNA, Ribosomal, 16S
PubMed: 22417292
DOI: 10.1111/j.1365-2761.2012.01350.x -
Genome Announcements Jan 2016We sequenced the complete genome of the highly virulent Aeromonas schubertii strain WL1483, which was isolated from diseased snakehead fish (Channa argus) in China. The...
We sequenced the complete genome of the highly virulent Aeromonas schubertii strain WL1483, which was isolated from diseased snakehead fish (Channa argus) in China. The full genome sequence of A. schubertii WL1483 is 4,400,034 bp, which encodes 4,376 proteins and contains 195 predicted RNA genes.
PubMed: 26798095
DOI: 10.1128/genomeA.01567-15 -
Journal of Fish Diseases Apr 2024The purpose of this study was to investigate whether a defensin-like antimicrobial peptide (C-13326 peptide) identified in Hermetia illucens could possess protective...
A novel defensin-like peptide C-13326 possesses protective effect against multidrug-resistant Aeromonas schubertii in hybrid snakehead (Channa maculate ♀ × Channa argus ♂).
The purpose of this study was to investigate whether a defensin-like antimicrobial peptide (C-13326 peptide) identified in Hermetia illucens could possess protective effect against multidrug-resistant Aeromonas schubertii in hybrid snakehead (Channa maculate ♀ × Channa argus ♂). The cDNA of C-13326 peptide comprised 243 nucleotides encoding 80 amino acids, with six conserved cysteine residues and the classical CSαβ structure. The recombinant expression plasmid pPIC9K-C-13326 was constructed and transformed into GS115 Pichia pastoris, and the C-13326 peptide was expressed by induction with 1% methanol. The crude extract of C-13326 peptide was precipitated by ammonium sulfate, assayed by Braford method, detected by tricine-SDS-PAGE, evaluated by BandScan software and identified by liquid chromatography-mass spectrometry. The C-13326 peptide was shown to have inhibitory activity against the growth of multidrug-resistant A. schubertii DM210910 by using the minimum growth inhibitory concentration and Oxford cup method. In addition, scanning electron microscopy analysis suggested that C-13326 peptide inhibited the growth of A. schubertii DM210910 by damaging the bacterial cell membrane. To explore the role of peptide C-13326 in vivo, hybrid snakehead was fed with peptide C-13326 as feed additives for 7 days. The results revealed that C-13326 peptide could significantly down-regulate the expression levels of IL-1β, IL-8, IL-12 and TNF-α (p < .05), and significantly improved the survival rate of hybrid snakehead after challenging with A. schubertii DM210910. Therefore, the C-13326 peptide is a promising antimicrobial agent for A. schubertii treatment in aquaculture.
Topics: Animals; Fish Diseases; Fishes; Aeromonas; Peptides; Defensins
PubMed: 38204197
DOI: 10.1111/jfd.13922