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Jundishapur Journal of Microbiology Jul 2015There are 4 different genera (i.e. Vibrio, Aliivibrio, Photobacterium, and Shewanella) in the new classification of bioluminescent bacteria. The mechanism of...
BACKGROUND
There are 4 different genera (i.e. Vibrio, Aliivibrio, Photobacterium, and Shewanella) in the new classification of bioluminescent bacteria. The mechanism of bioluminescence has yet to be fully elucidated. Therefore, the determination of physiological and genetic characteristics of bioluminescent bacteria isolated from different sources is very important. Pulsed-Field Gel Electrophoresis (PFGE) has the highest discriminatory power among the different molecular typing methods for the investigation of the clonal relationships between bacteria. For the PFGE analysis of bioluminescent bacteria, the NotI-HF™ is the method of choice among the restriction enzymes.
OBJECTIVES
The present study aimed to determine genetic relatedness via PFGE in 41 bioluminescent bacteria (belonging to 10 different species) isolated and identified from various marine sources.
MATERIALS AND METHODS
Different bioluminescent bacteria (i.e. Vibrio gigantis, V. azureus, V. harveyi, V. lentus, V. crassostreae, V. orientalis, Aliivibrio logei, A. fischeri, Shewanella woodyi, and Photobacterium kishitanii) were analyzed by PFGE using the NotI-HF™ restriction enzyme. The whole DNA of the strains embedded into the agarose plugs was digested with enzyme at 37°C for 30 minutes. CHEF-Mapper PFGE system was used for electrophoresis and band profile of the strains for the NotI-HF™ restriction enzyme were analyzed by Bio-Profil-1D++ software (Vilber Lourmat) at 10% homology coefficient.
RESULTS
Although all experiments were performed three times, four of forty-one bioluminescent strains (V. gigantis E-16, H-16 and S3W46 strains and A. fischeri E-4 strain) could not be typed by PFGE technique with NotI-HF™ enzyme. While only two strains (V. crassostreae H-12 and H-19 strains) were exhibiting same band pattern profiles (100% genome homology), thirty-six different PFGE band patterns were obtained. Pattern homologies changed between 66% - 92%, 73% - 83% and 49% - 100% for V. gigantis, V. harveyi and other strains, respectively.
CONCLUSIONS
The obtained results revealed that there has been a high rate of genetic diversity in bioluminescent strains isolated from Gulf of Izmir and V. lentus and V. crassostreae strains could be also bioluminescent for the first report. At the same time, PFGE analysis of bioluminescent bacteria including four different genera and ten different species were shown for the first time by this study. It is considered that data acquired by this study will contribute evolution and mechanism of bioluminescence to further works to be done.
PubMed: 26421141
DOI: 10.5812/jjm.28378v2 -
Frontiers in Immunology 2021The range of metabolic pathways that are dependent on a proper supply of specific amino acids (AA) unveils their importance in the support of health. AA play central...
The range of metabolic pathways that are dependent on a proper supply of specific amino acids (AA) unveils their importance in the support of health. AA play central roles in key pathways vital for immune support and individual AA supplementation has shown to be able to modulate fish immunity. trials are important tools to evaluate the immunomodulatory role of AA, and the present study was conceived to evaluate methionine and tryptophan roles in immune-related mechanisms aiming to understand their effects in leucocyte functioning and AA pathways. For that purpose, head-kidney leucocytes were isolated and a primary cell culture established. The effect of methionine or tryptophan surplus on cell viability was assessed. Medium L-15 10% FBS without AA addition (0.5mM of L-methionine, 0.1 mM of L-tryptophan) was used as control. To that, L-methionine or L-tryptophan were supplemented at 1 and 2 times (M1x or M2x, and T1x or T2x). Nitric oxide, ATP, total antioxidant capacity, and immune-related genes were evaluated in response to lipopolysaccharides extracted from subsp. or UV-inactivated bacteria). Moreover, caspase 3 activity and apoptosis-related genes were evaluated in response to the apoptosis-inducing protein, AIP56. Distinct roles in leucocytes' immune response were observed, with contrasting outcomes in the modulation of individual pathways. Methionine surplus improved cell viability, polyamine production, and methionine-related genes expression in response to an inflammatory agent. Also, methionine supplementation lowered signals of apoptosis by AIP56, presenting lower caspase 3 activity and higher and expression. Cells cultured in tryptophan supplemented medium presented signals of an attenuated inflammatory response, with decreased ATP and enhanced expression of anti-inflammatory and catabolism-related genes in macrophages. In response to AIP56, leucocytes cultured in a tryptophan-rich medium presented lower resilience to the toxin, higher caspase 3 activity and expression of caspase 8, and lower expression of several genes, including and . This study showed the ability of methionine surplus to improve leucocytes' response to an inflammatory agent and to lower signals of apoptosis by AIP56 induction, while tryptophan attenuated several cellular signals of the inflammatory response to UV-inactivated bacteria and lowered leucocyte resilience to AIP56.
Topics: Animals; Apoptosis; Bass; Cells, Cultured; Culture Media; Head Kidney; Immunity, Innate; Immunomodulation; Leukocytes; Lipopolysaccharides; Methionine; Photobacterium; Tryptophan
PubMed: 33790917
DOI: 10.3389/fimmu.2021.660448 -
Journal of Applied Microbiology 2003To detect Photobacterium damselae ssp. piscicida using the PCR technique and plating method.
AIMS
To detect Photobacterium damselae ssp. piscicida using the PCR technique and plating method.
METHODS AND RESULTS
Two strains of P. damselae ssp. piscicida were isolated from cultured cobia (Rachycentron canadum) at two different fish farms in Taiwan. A pair of primers was designed to detect the capsular polysaccharide gene of P. damselae ssp. piscicida by PCR. Reference strains of different genus and different clinical strains were used for this study. The expected product (410 bp) was obtained from both P. damselae ssp. piscicida and P. damselae ssp. damselae, and they were differentiated by culturing on thiosulphate citrate bile salts-sucrose agar (TCBS-1). Photobacterium damselae ssp. damselae grew on TCBS-1 producing green colonies whereas P. damselae ssp. piscicida did not grow.
CONCLUSIONS
The methods used are cost and labour effective when compared with the other methods and commercially available kits.
SIGNIFICANCE AND IMPACT OF THE STUDY
This work provides an integrated set of methods to identify the species P. damselae and to differentiate P. damselae ssp. piscicida from P. damselae ssp. damselae.
Topics: Animals; Aquaculture; Bacterial Typing Techniques; Base Sequence; DNA, Bacterial; Fish Diseases; Fishes; Gram-Negative Bacterial Infections; Molecular Sequence Data; Photobacterium; Polymerase Chain Reaction
PubMed: 14633013
DOI: 10.1046/j.1365-2672.2003.02119.x -
Frontiers in Microbiology 2023The mud crab, , holds great commercial significance as a marine crustacean widely cultivated in the Indo-Pacific region. Understanding the core gut microbiota of aquatic...
INTRODUCTION
The mud crab, , holds great commercial significance as a marine crustacean widely cultivated in the Indo-Pacific region. Understanding the core gut microbiota of aquatic animals is crucial for their overall health and growth, yet the core gut microbiota of mud crab remains poorly characterized.
METHODS
In this study, we gathered gut samples from mud crabs across five locations within Sanmen Bay, China. Through the utilization of high-throughput sequencing, we delved into the composition of the gut microbial community and identified the core gut microbiome of mud crab.
RESULTS
Our results demonstrate that the gut microbial diversity of mud crab did not exhibit significant variation among the five sampling sites, although there were some differences in community richness. At the phylum level, we identified 35 representative phyla, with Firmicutes, Proteobacteria, Bacteroidota, and Campilobacterota as the dominant phyla. Among the 815 representative genera, we discovered 19 core genera, which accounted for 65.45% of the total sequences. These core genera were distributed across 6 phyla, and among them, exhibited the highest average relative abundance.
DISCUSSION
has probiotic activity and may play a crucial role in enhancing the immune response of the host and maintaining the diversity of the gut microbiota. Moreover, we observed a positive correlation between the relative abundance of core genera and the stability of the gut microbial community. Furthermore, our findings revealed distinct differences in gut microbial composition and specific taxa between the sexes of mud crab. These differences subsequently influenced the functionality of the gut microbial community. Overall, our investigation sheds light on the core gut microbiota of mud crab, emphasizing the importance of core gut microbial communities in maintaining the health and growth of these commercially significant marine crustaceans.
PubMed: 37727291
DOI: 10.3389/fmicb.2023.1243334 -
ACS Chemical Biology May 2018The lack of α2-6-linkage specific sialidases limits the structural and functional studies of sialic-acid-containing molecules. Photobacterium damselae...
The lack of α2-6-linkage specific sialidases limits the structural and functional studies of sialic-acid-containing molecules. Photobacterium damselae α2-6-sialyltransferase (Pd2,6ST) was shown previously to have α2-6-specific, but weak, sialidase activity. Here, we develop a high-throughput blue-white colony screening method to identify Pd2,6ST mutants with improved α2-6-sialidase activity from mutant libraries generated by sequential saturation mutagenesis. A triple mutant (Pd2,6ST S232L/T356S/W361F) has been identified with 100-fold improved activity, high α2-6-sialyl linkage selectivity, and ability to cleave two common sialic acid forms, N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc). It is a valuable tool for sialoglycan structural analysis and functional characterization. The sequential saturation mutagenesis and screening strategy developed here can be explored to evolve other linkage-specific neoglycosidases from the corresponding glycosyltransferases.
Topics: Bacterial Proteins; High-Throughput Screening Assays; Hydrogen-Ion Concentration; Kinetics; Mutagenesis; Mutation; Neuraminidase; Photobacterium; Sialyltransferases; Substrate Specificity
PubMed: 29543427
DOI: 10.1021/acschembio.8b00002 -
MSystems Jun 2023Facultative marine bacterial pathogens sense environmental signals so that the expression of virulence factors is upregulated on entry into hosts and downregulated...
Facultative marine bacterial pathogens sense environmental signals so that the expression of virulence factors is upregulated on entry into hosts and downregulated during the free-living lifestyle in the environment. In this study, we utilized transcriptome sequencing to compare the transcriptional profiles of subsp. , a generalist pathogen that causes disease in diverse marine animals and fatal infections in humans at NaCl concentrations that mimic the free-living lifestyle or host internal milieu, respectively. We here show that NaCl concentration constitutes a major regulatory signal that shapes the transcriptome and uncover 1,808 differentially expressed genes (888 upregulated and 920 downregulated in response to low-salt conditions). Growth at 3% NaCl, a salinity that mimics the free-living lifestyle, upregulated genes involved in energy production, nitrogen metabolism, transport of compatible solutes, utilization of trehalose and fructose, and carbohydrate and amino acid metabolism with strong upregulation of the arginine deiminase system (ADS). In addition, we observed a marked increase in resistance to antibiotics at 3% NaCl. On the contrary, the low salinity conditions (1% NaCl) that mimic those encountered in the host triggered a virulence gene expression profile that maximized the production of the type 2 secretion system (T2SS)-dependent cytotoxins damselysin, phobalysin P, and a putative PirAB-like toxin, observations that were corroborated by the analysis of the secretome. Low salinity also upregulated the expression of iron-acquisition systems, efflux pumps, and other functions related to stress response and virulence. The results of this study greatly expand our knowledge of the salinity-responsive adaptations of a generalist and versatile marine pathogen. IMPORTANCE Pathogenic species experience continuous shifts of NaCl concentration in their life cycles. However, the impact of salinity changes in gene regulation has been studied in a small number of species. In this study, we analyzed the transcriptional response of subsp. (), a generalist and facultative pathogen, to changes in salinity, and demonstrate that growth at 1% NaCl in comparison to 3% NaCl triggers a virulence program of gene expression, with a major impact in the T2SS-dependent secretome. The decrease in NaCl concentration encountered by bacteria on entry into a host is proposed to constitute a regulatory signal that upregulates a genetic program involved in host invasion and tissue damage, nutrient scavenging (notably iron), and stress responses. This study will surely inspire new research on pathobiology, as well as on other important pathogens of the family and related taxa whose salinity regulons still await investigation.
Topics: Humans; Animals; Virulence; Sodium Chloride; Salinity; Photobacterium; Iron
PubMed: 37288979
DOI: 10.1128/msystems.01253-22 -
PloS One 2013Photobacterium profundum SS9 is a Gram-negative bacterium, originally collected from the Sulu Sea. Its genome consists of two chromosomes and a 80 kb plasmid. Although...
Photobacterium profundum SS9 is a Gram-negative bacterium, originally collected from the Sulu Sea. Its genome consists of two chromosomes and a 80 kb plasmid. Although it can grow under a wide range of pressures, P. profundum grows optimally at 28 MPa and 15°C. Its ability to grow at atmospheric pressure allows for both easy genetic manipulation and culture, making it a model organism to study piezophily. Here, we report a shotgun proteomic analysis of P. profundum grown at atmospheric compared to high pressure using label-free quantitation and mass spectrometry analysis. We have identified differentially expressed proteins involved in high pressure adaptation, which have been previously reported using other methods. Proteins involved in key metabolic pathways were also identified as being differentially expressed. Proteins involved in the glycolysis/gluconeogenesis pathway were up-regulated at high pressure. Conversely, several proteins involved in the oxidative phosphorylation pathway were up-regulated at atmospheric pressure. Some of the proteins that were differentially identified are regulated directly in response to the physical impact of pressure. The expression of some proteins involved in nutrient transport or assimilation, are likely to be directly regulated by pressure. In a natural environment, different hydrostatic pressures represent distinct ecosystems with their own particular nutrient limitations and abundances. However, the only variable considered in this study was atmospheric pressure.
Topics: Adaptation, Physiological; Bacterial Proteins; Chromosomes, Bacterial; Gene Expression Profiling; Gene Expression Regulation, Bacterial; Hydrostatic Pressure; Mechanotransduction, Cellular; Photobacterium; Plasmids; Proteomics; Seawater
PubMed: 23741291
DOI: 10.1371/journal.pone.0060897 -
Environmental Microbiology Oct 2005Substantial ambiguity exists regarding the phylogenetic status of facultatively psychrophilic luminous bacteria identified as Photobacterium phosphoreum, a species...
Substantial ambiguity exists regarding the phylogenetic status of facultatively psychrophilic luminous bacteria identified as Photobacterium phosphoreum, a species thought to be widely distributed in the world's oceans and believed to be the specific bioluminescent light-organ symbiont of several deep-sea fishes. Members of the P. phosphoreum species group include luminous and non-luminous strains identified phenotypically from a variety of different habitats as well as phylogenetically defined lineages that appear to be evolutionarily distinct. To resolve this ambiguity and to begin developing a meaningful knowledge of the geographic distributions, habitats and symbiotic relationships of bacteria in the P. phosphoreum species group, we carried out a multilocus, fine-scale phylogenetic analysis based on sequences of the 16S rRNA, gyrB and luxABFE genes of many newly isolated luminous strains from symbiotic and saprophytic habitats, together with previously isolated luminous and non-luminous strains identified as P. phosphoreum from these and other habitats. Parsimony analysis unambiguously resolved three evolutionarily distinct clades, phosphoreum, iliopiscarium and kishitanii. The tight phylogenetic clustering within these clades and the distinct separation between them indicates they are different species, P. phosphoreum, Photobacterium iliopiscarium and the newly recognized 'Photobacterium kishitanii'. Previously reported non-luminous strains, which had been identified phenotypically as P. phosphoreum, resolved unambiguously as P. iliopiscarium, and all examined deep-sea fishes (specimens of families Chlorophthalmidae, Macrouridae, Moridae, Trachichthyidae and Acropomatidae) were found to harbour 'P. kishitanii', not P. phosphoreum, in their light organs. This resolution revealed also that 'P. kishitanii' is cosmopolitan in its geographic distribution. Furthermore, the lack of phylogenetic variation within 'P. kishitanii' indicates that this facultatively symbiotic bacterium is not cospeciating with its phylogenetically divergent host fishes. The results of this fine-scale phylogenetic analysis support the emerging view that bacterial species names should designate singular historical entities, i.e. discrete lineages diagnosed by a significant divergence of shared derived nucleotide characters.
Topics: Animals; DNA Gyrase; DNA, Ribosomal; Ecosystem; Environment; Evolution, Molecular; Fishes; Luminescent Proteins; Molecular Sequence Data; Photobacterium; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Species Specificity; Symbiosis
PubMed: 16156737
DOI: 10.1111/j.1462-2920.2005.00859.x -
Genome Announcements Oct 2014Bacteria associated with the Eastern oysters (Crassostrea virginica) native to Apalachicola Bay, FL, were investigated using 16S rRNA gene amplicon metagenomic...
Bacteria associated with the Eastern oysters (Crassostrea virginica) native to Apalachicola Bay, FL, were investigated using 16S rRNA gene amplicon metagenomic sequencing which revealed that the oyster microbiome was predominated by Cyanobacteria and Proteobacteria. We also found that the oyster tissues were predominated by the pathogenic and symbiotic Photobacterium spp. (formerly known as Vibrio damselae).
PubMed: 25342691
DOI: 10.1128/genomeA.01083-14 -
Molecules (Basel, Switzerland) Oct 2022The use of phytogenic extracts is considered a sustainable strategy for the prevention of fish diseases, including as a potential option due to their variety of...
Antibacterial and Antiparasitic Activity of Propyl-Propane-Thiosulfinate (PTS) and Propyl-Propane-Thiosulfonate (PTSO) from against Gilthead Sea Bream Pathogens in In Vitro and In Vivo Studies.
The use of phytogenic extracts is considered a sustainable strategy for the prevention of fish diseases, including as a potential option due to their variety of bioactive compounds. In this study, we analyzed the antibacterial and antiparasitic potential of propyl-propane-thiosulfinate (PTS) and propyl-propane-thiosulfonate (PTSO) from onions. The in vitro activity against , , and of both compounds was tested. In addition, the viability of larvae was evaluated. Moreover, a diet that consisted of a blend of PTS/PTSO (ALLIUM) was used. A total of 90 gilthead sea bream juveniles were tested against subsp. after 12 weeks of dietary administration. Furthermore, 150 fish with a rate of 10-15 parasites/fish were fed for 21 days and the number of gill parasites was recorded. All strains were sensitive to both compounds. PTSO showed the highest inhibitory effect against all target strains, while PTS showed higher effectiveness against Fish from ALLIUM group presented the highest probability of survival, increasing up to 91.1%, whereas in the control group, the probability of survival was 66.7%. The number of parasites in the gilthead sea bream decreased in the ALLIUM group over time. These results suggest the inclusion of PTS and PTSO in feed as a natural strategy to prevent antibacterial and antiparasitic fish diseases.
Topics: Animals; Sea Bream; Onions; Propane; Antiparasitic Agents; Anti-Bacterial Agents; Allium; Fish Diseases; Plant Extracts
PubMed: 36296491
DOI: 10.3390/molecules27206900