Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.845
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-33480834

RESUMO

A Gram-strain-negative, facultatively anaerobic, motile, rod-shaped and flagellated marine bacterium, designated SM6T, was isolated from surface seawater collected in Daya Bay (Guangdong, China). Phylogenetic analysis based on 16S rRNA gene sequences, multilocus sequence analysis, phylogenomic analysis of single-copy gene families and whole genome data showed that strain SM6T belonged to the genus Vibrio. The closest phylogenetic relatives of SM6T were Vibrio plantisponsor MSSRF60T (97.38 % 16S rRNA gene sequence pairwise similarity), Vibrio variabilis R-40492T (97.27 %), Vibrio aestuarianus ATCC 35048T (97.21 %) and Vibrio sagamiensis LC2-047T (97.3 %). Growth of strain SM6T occurred at 10-45 °C (optimum 30 °C), at pH 6.0-9.0 (optimum 6.0) and in the presence of 0-10 % (w/v) NaCl (optimum 3-8 %). The predominant fatty acids (>10 %) were summed feature 3 (C16 : 1 ω7c or/and C16 : 1 ω6c), C16 : 0 and summed feature 8 (C18 : 1 ω7c or/and C18 : 1 ω6c). The DNA G+C content of the assembled genomic sequences was 47.37 % for strain SM6T. Average nucleotide identity values between SM6T and its reference species were lower than the threshold for species delineation (95-96 %); in silico DNA-DNA hybridization further showed that the strains shared less than 70 % similarity. On the basis of evidence from the present polyphasic study, strain SM6T is considered to represent a novel species of the genus Vibrio, for which the name Vibrio agarilyticus sp. nov. is proposed. The type strain is SM6T (=KCTC 82076T=MCCC 1K04327 T).


Assuntos
Filogenia , Água do Mar/microbiologia , Vibrio/classificação , Ágar/metabolismo , Técnicas de Tipagem Bacteriana , Composição de Bases , Baías , China , DNA Bacteriano/genética , Ácidos Graxos/química , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vibrio/isolamento & purificação
2.
Artigo em Inglês | MEDLINE | ID: mdl-33507857

RESUMO

Cockle mortality events have been reported in northern France since 2012. In the present study, we describe and investigate the implication of a potential bacterial causative agent in cockle mortality. Bacteria isolated from five different cockle mortality events were characterized and studied. Using phenotypic analysis combined with DNA-DNA hybridization (DDH) and whole genome sequencing, the isolates were shown to belong to Vibrio aestuarianus, a species regularly detected in France during oyster mortality events. Comparison of the strains from cockles with strains from French oysters and the type strain showed that the strains from cockles were genetically different to those from oysters and also different to the V. aestuarianus type strain. Moreover, the cockle and oyster strains were classified into two different, but close, groups both separated from the type strain by: (1) analyses of the ldh gene sequences; (2) DDH assays between 12/122 3T3T (LMG 31436T=DSM 109723T), a representative cockle strain, 02/041T (CIP 109791T=LMG 24517T) representative oyster strain and V. aestuarianus type strain LMG 7909T; (3) average nucleotide identity values calculated on the genomes; and (4) phenotypic traits. Finally, results of MALDI-TOF analyses also revealed specific peaks discriminating the three representative strains. The toxicity of representative strains of these cockle isolates was demonstrated by experimental infection of hatchery-produced cockles. The data therefore allow us to propose two novel subspecies of Vibrio aestuarianus: Vibrio aestuarianus subsp. cardii subsp. nov. for the cockle strains and Vibrio aestuarianus subsp. francensis subsp. nov. for the Pacific oyster strains, in addition to an emended description of the species Vibrio aestuarianus.


Assuntos
Cardiidae/microbiologia , Filogenia , Vibrio/classificação , Animais , Técnicas de Tipagem Bacteriana/métodos , Composição de Bases , DNA Bacteriano/genética , França , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vibrio/isolamento & purificação
3.
PLoS One ; 15(8): e0237704, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804963

RESUMO

Since plastics degrade very slowly, they remain in the environment on much longer timescales than most natural organic substrates and provide a novel habitat for colonization by bacterial communities. The spectrum of relationships between plastics and bacteria, however, is little understood. The first objective of this study was to examine plastics as substrates for communities of Bacteria in estuarine surface waters. We used next-generation sequencing of the 16S rRNA gene to characterize communities from plastics collected in the field, and over the course of two colonization experiments, from biofilms that developed on plastic (low-density polyethylene, high-density polyethylene, polypropylene, polycarbonate, polystyrene) and glass substrates placed in the environment. Both field sampling and colonization experiments were conducted in estuarine tributaries of the lower Chesapeake Bay. As a second objective, we concomitantly analyzed biofilms on plastic substrates to ascertain the presence and abundance of Vibrio spp. bacteria, then isolated three human pathogens, V. cholerae, V. parahaemolyticus, and V. vulnificus, and determined their antibiotic-resistant profiles. In both components of this study, we compared our results with analyses conducted on paired samples of estuarine water. This research adds to a nascent literature that suggests environmental factors govern the development of bacterial communities on plastics, more so than the characteristics of the plastic substrates themselves. In addition, this study is the first to culture three pathogenic vibrios from plastics in estuaries, reinforcing and expanding upon earlier reports of plastic pollution as a habitat for Vibrio species. The antibiotic resistance detected among the isolates, coupled with the longevity of plastics in the aqueous environment, suggests biofilms on plastics have potential to persist and serve as focal points of potential pathogens and horizontal gene transfer.


Assuntos
Biofilmes/efeitos dos fármacos , Estuários , Plásticos , Vibrio/isolamento & purificação , Poluentes da Água , Antibacterianos/farmacologia , Oceano Atlântico , DNA Bacteriano/isolamento & purificação , Farmacorresistência Bacteriana/genética , Transferência Genética Horizontal , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Vibrio/efeitos dos fármacos , Vibrio/genética
4.
Int J Syst Evol Microbiol ; 70(9): 5149-5155, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32812859

RESUMO

A Gram-stain-negative, oxidase- and catalase-positive, facultative anaerobic and rod-shaped bacterium, designated strain SM1977T, was isolated from the surface of coralline algae collected from the intertidal zone at Qingdao, PR China. The strain grew at 10-35 °C, pH 4.5-8.5 and with 1-8.5% (w/v) NaCl. It reduced nitrate to nitrite and hydrolysed Tween 20 and DNA. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain SM1977T was affiliated with the genus Vibrio, having the highest sequence similarity (97.6 %) to the type strain of Vibrio casei, followed by those of another five species (95.6-97.6 %) in the Rumoiensis clade of the genus Vibrio. However, the in silico DNA-DNA hybridization (75.3-75.9 %) and average nucleotide identity (21.6-22.8 %) values of SM1977T against these close relatives were all below the corresponding thresholds to discriminate bacterial species. The major fatty acids were summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), C16:0 and summed feature 8 (C18:1 ω6c and /or C18:1 ω7c). The predominant polar lipids were phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. The sole respiratory quinone was Q-8. The genomic DNA G+C content of strain SM1977T, determined from the obtained whole genomic sequence, was 42.3 mol%. On the basis of the polyphasic results obtained in this study, strain SM1977T is considered to represent a novel species within the genus Vibrio, for which the name Vibrio algicola sp. nov. is proposed. The type strain is SM1977T (=MCCC 1K04351T=KCTC 72847T).


Assuntos
Antozoários/microbiologia , Clorófitas/microbiologia , Filogenia , Vibrio/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química , Vibrio/isolamento & purificação
5.
Mar Environ Res ; 157: 104864, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32275501

RESUMO

Microbial contamination of aggregates collected near an Atlantic salmon farm, in the Cherbourg roadstead, was followed monthly over one year to study the dynamics of Vibrio spp. and explore their impact on farmed fish. Salmon state of health was followed through blood and histopathological analyses. Vibrio were systematically found in aggregates with particularly high concentration in August. The Splendidus clade was strongly dominant in aggregates as well as in gills, and an increase in Vibrio diversity was observed in summer and autumn. Results did not demonstrate that aggregates directly impact the bacterial community of gills, but they suggested an aggregates-gills interaction. Gill contamination was correlated with water temperature and probably impacted by amoebae. Vibrio renipiscarius and Vibrio toranzoniae were isolated in North Atlantic for the first time. A better understanding of the interaction between marine aggregates, Vibrio spp. and fish is essential to improve salmon cage farming.


Assuntos
Aquicultura , Doenças dos Peixes/microbiologia , Salmo salar/microbiologia , Vibrio/isolamento & purificação , Animais , Oceano Atlântico , Brânquias/microbiologia , Estações do Ano , Vibrio/classificação
6.
J Appl Microbiol ; 129(3): 738-752, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32155682

RESUMO

AIMS: To explore a prokaryotic species-specific DNA marker, 16S-23S rRNA gene internal transcribed spacer (ITS) sequence for identification and classification of Vibrio. METHODS AND RESULTS: Five hundred and seventy four ITS sequences from 60 Vibrio strains were collected, then the primary and secondary structures of ITS sequence were analysed. The ITS was divided into several subunits, and the species-specificity of these subunits were evaluated by blast. The variable subunit of ITS showed high species-specificity. A protocol to identify a Vibrio species based on ITS analysis was developed and verified. Both the specificity and sensitivity were 100%. The phylogeny analysis of Vibrio based on ITS showed that ITS devised a better classification than 16S rDNA. Finally, an identification method of Vibrio based on ITS sequencing in food samples was developed and evaluated. The results of ITS sequencing were (100%) consistent with the results identified by ISO standard. CONCLUSIONS: Vibrio could be accurately identified at the species level by using the ITS sequences. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study suggests that the ITS can be considered as a significant DNA marker for identification and classification of Vibrio species, and it posed a new path to screen the Vibrio in food sample.


Assuntos
DNA Espaçador Ribossômico/genética , Vibrio/classificação , Vibrio/isolamento & purificação , DNA Bacteriano/genética , Genes Bacterianos/genética , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Especificidade da Espécie , Vibrio/genética
7.
Sci Rep ; 10(1): 2719, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066764

RESUMO

The white leg Litopenaeus vannamei shrimp is of importance to the eastern Pacific fisheries and aquaculture industry but suffer from diseases such as the recently emerged early mortality syndrome. Many bacterial pathogens have been identified but the L. vannamei microbiota is still poorly known. Using a next-generation sequencing (NGS) approach, this work evaluated the impact of the inclusion in the diet of mannan oligosaccharide, (MOS, 0.5% w/w), over the L. vannamei microbiota and production behavior of L. vannamei under intensive cultivation in Ecuador. The MOS supplementation lasted for 60 days, after which the shrimp in the ponds were harvested, and the production data were collected. MOS improved productivity outcomes by increasing shrimp survival by 30%. NGS revealed quantitative differences in the shrimp microbiota between MOS and control conditions. In the treatment with inclusion of dietary MOS, the predominant phylum was Actinobacteria (28%); while the control group was dominated by the phylum Proteobacteria (30%). MOS has also been linked to an increased prevalence of Lactococcus- and Verrucomicrobiaceae-like bacteria. Furthermore, under the treatment of MOS, the prevalence of potential opportunistic pathogens, like Vibrio, Aeromonas, Bergeyella and Shewanella, was negligible. This may be attributable to MOS blocking the adhesion of pathogens to the surfaces of the host tissues. Together, these findings point to the fact that the performance (survival) improvements of the dietary MOS may be linked to the impact on the microbiota, since bacterial lines with pathogenic potential towards shrimps were excluded in the gut.


Assuntos
Actinobacteria/fisiologia , Aquicultura/métodos , Mananas/administração & dosagem , Microbiota , Oligossacarídeos/administração & dosagem , Penaeidae/microbiologia , Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Aeromonas/isolamento & purificação , Aeromonas/patogenicidade , Ração Animal , Animais , Aderência Bacteriana , Equador , Flavobacteriaceae/isolamento & purificação , Flavobacteriaceae/patogenicidade , Lactococcus/isolamento & purificação , Lactococcus/fisiologia , Longevidade/fisiologia , Proteobactérias/classificação , Proteobactérias/isolamento & purificação , Proteobactérias/fisiologia , Alimentos Marinhos/microbiologia , Alimentos Marinhos/provisão & distribução , Shewanella/isolamento & purificação , Shewanella/patogenicidade , Verrucomicrobia/classificação , Verrucomicrobia/isolamento & purificação , Verrucomicrobia/fisiologia , Vibrio/isolamento & purificação , Vibrio/patogenicidade
8.
PLoS One ; 15(2): e0228711, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32053660

RESUMO

Fasting has been shown to increase longevity and alter immune function in a variety of animals, but little is understood about how reduced caloric intake may impact regeneration and infections in animals that must regularly repair and regenerate tissue in marine environments that contain high levels of bacteria. We examined the possibility that fasting could enhance spine regeneration and reduce bacteremia in the purple sea urchin Strongylocentrotus purpuratus. A small number of spines were removed from urchins and rates of spine regrowth and levels of culturable bacteria from the coelomic fluid were measured for 21 days in fed and fasted urchins. Fasted urchins had higher rates of spine regrowth and lower levels of colony-forming units (CFU) per milliliter of coeolomic fluid. The predominant bacteria in the coelomic fluid was isolated and identified by DNA sequence-based methods as Vibrio cyclitrophicus. After 21 days, fasted and fed urchins were injected with V. cyclitrophicus. Two hours after injection, fed urchins had about 25% more culturable bacteria remaining in their coelomic fluid compared to fasted urchins. We found no evidence that fasting altered coelomic fluid cell number or righting response, indicators of physiologic and behavioral stress in urchins. Our results demonstrate that V. cyclitrophicus is present in purple urchin coelomic fluid, that fasting can increase spine regeneration and that fasted urchins have much lower levels of culturable bacteria in their coelomic fluid than fed urchins. Overall, our data suggests that fasting may ultimately reduce bacteremia and infection in injured or damaged urchins.


Assuntos
Bacteriemia/prevenção & controle , Jejum , Regeneração , Coluna Vertebral/fisiologia , Strongylocentrotus purpuratus/fisiologia , Animais , Bacteriemia/veterinária , Strongylocentrotus purpuratus/microbiologia , Vibrio/isolamento & purificação , Vibrio/patogenicidade
9.
Arch Microbiol ; 202(5): 1097-1106, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32040595

RESUMO

Vibrios are a group of very important bacterial pathogens in marine aquaculture industry and cause serious aquatic animal diseases, such as shrimp acute hepatopancreatic necrosis disease (AHPND). A new AHPND pathogen, the Vibrio owensii strain SH-14, was isolated from diseased shrimp in Shanghai, China. In this study, to better understand the pathogenesis of AHPND at the genomic level, the genome of the strain SH-14 was completely sequenced and analyzed. The SH-14 consists of two circular chromosomes of 3,689,702 bp and 2,430,445 bp, and of two plasmids named as pVHvo (69,148 bp) and pVHvo-R (78,918 bp), respectively. The pVHvo encodes the bi-toxic genes of pirAB, responsible for shrimp AHPND. The whole genomes contain a total of 5703 predicted open reading frames (ORFs), 129 tRNA genes and 37 rRNA genes. The average nucleotide identities (ANIs) between the SH-14 and the other V. owensii strains are all greater than 95%, confirming a new V. owensii strain of the SH-14. The taxonomic affiliation of the SH-14 is also supported by whole-genome alignment and nucleotide identity dotplot analyses. These results pave the way for further study of spread and epidemic of shrimp AHPND.


Assuntos
Genoma Bacteriano/genética , Hepatopâncreas/microbiologia , Penaeidae/microbiologia , Alimentos Marinhos/microbiologia , Vibrio/genética , Animais , Aquicultura , Sequência de Bases , China , Genômica , Hepatopâncreas/patologia , Plasmídeos/genética , Análise de Sequência de DNA , Vibrio/isolamento & purificação
10.
BMC Infect Dis ; 20(1): 104, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019500

RESUMO

BACKGROUND: Vibrio spp. are aquatic bacteria that are ubiquitous in warm estuarine and marine environments, of which 12 species are currently known to cause infections in humans. So far, only five human infections with V. harveyi have been reported. CASE PRESENTATION: A 26-year old patient was transferred to our center by inter-hospital air transfer from Mallorca, Spain. Seven days before, he had suffered a complete amputation injury of his left lower leg combined with an open, multi-fragment, distal femur fracture after he had been struck by the propeller of a passing motorboat while snorkeling in the Mediterranean Sea. On admission he was febrile; laboratory studies showed markedly elevated inflammatory parameters and antibiotic treatment with ampicillin/sulbactam was initiated. Physical examination showed a tender and erythematous amputation stump, so surgical revision was performed and confirmed a putrid infection with necrosis of the subcutaneous tissue and the muscles. Tissue cultures subsequently grew V. harveyi with a minimal inhibitory concentration (MIC) of 16 mg/L for ampicillin, and antibiotic treatment was switched to ceftriaxone and ciprofloxacin. Throughout the following days, the patient repeatedly had to undergo surgical debridement but eventually the infection could be controlled, and he was discharged. CONCLUSIONS: We report the first human infection with V. harveyi acquired in Spain and the second infection acquired in the Mediterranean Sea. This case suggests that physicians and microbiologists should be aware of the possibility of wound infections caused by Vibrio spp. acquired in the ocean environment, especially during hot summer months. Since Vibrio spp. preferentially grow at water temperatures above 18 °C, global warming is responsible for an abundance of these bacteria in coastal waters. This will likely lead to a worldwide increase in reports of Vibrio-associated diseases in the future.


Assuntos
Amputação Traumática/complicações , Traumatismos da Perna/cirurgia , Infecção da Ferida Cirúrgica/microbiologia , Vibrio/genética , Adulto , Antibacterianos/uso terapêutico , Humanos , Masculino , Testes de Sensibilidade Microbiana , Navios/instrumentação , Espanha , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/etiologia , Vibrio/efeitos dos fármacos , Vibrio/isolamento & purificação , Vibrioses/microbiologia
11.
BMC Infect Dis ; 20(1): 60, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959118

RESUMO

BACKGROUND: Necrotizing fasciitis (NF) is a rare and life-threatening necrotizing skin and soft-tissue infection. Infectious pathogens of NF must be detected early and treated rapidly to prevent loss of limb or a fatal outcome. This study aimed to detect more reliable predictors between gram-negative and gram-positive monomicrobial NF of limbs. METHODS: A total of 100 patients with limb monomicrobial NF were diagnosed prospectively from April 2015 to July 2018. These monomicrobial NF pathogens can be divided into gram-negative and gram-positive groups according to the result of Gram staining and final bacterial reports. Data such as demographics, seawater or seafood contact history, infectious location, comorbidities, presenting signs and symptoms, and laboratory findings were recorded and compared. RESULTS: A total of 55 patients were infected with gram-negative organisms and 45 patients with gram-positive organisms. Among the 55 cases of monomicrobial gram-negative NF, 48 (87.3%) were caused mainly by Vibrio spp. (38, 69.1%) and Aeromonas spp. (10, 18.2%). A higher incidence of chronic kidney disease, cerebrovascular accident, tachypnea, and septic shock; a higher rate of band forms of leukocytes of more than 3%, serum lactate of more than 20 mg/dL, and C-reactive protein level of less than 150 mg/dL; prolonged prothrombin time; and a lower fibrinogen level were observed in patients with gram-negative infection. In a multivariate analysis, a higher incidence of seawater or seafood contact history (odds ratio [OR]: 66.301; 95% confidence interval [CI]: 7.467-588.702), a higher rate of hyperlactatemia (OR: 7.904; 95% CI: 1.231-50.744), and a low fibrinogen level (OR: 1.013; 95% CI: 1.004-1.023) indicated gram-negative infection. CONCLUSIONS: In southern Taiwan, NF of limbs mainly affected the lower limbs, exhibited monomicrobial infection, and was predominated by gram-negative bacteria. Gram-negative monomicrobial NF of limbs often occurred in individuals with the more seawater or seafood contact history, hyperlactatemia, and low fibrinogen levels.


Assuntos
Aeromonas/isolamento & purificação , Fasciite Necrosante/epidemiologia , Fasciite Necrosante/microbiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções dos Tecidos Moles/epidemiologia , Infecções dos Tecidos Moles/microbiologia , Vibrio/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , Fasciite Necrosante/diagnóstico , Feminino , Infecções por Bactérias Gram-Negativas/diagnóstico , Humanos , Incidência , Extremidade Inferior/microbiologia , Extremidade Inferior/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Infecções dos Tecidos Moles/diagnóstico , Taiwan/epidemiologia
12.
J Appl Microbiol ; 129(1): 17-36, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31977129

RESUMO

AIM: The current study was conducted to determine the incidence, antibiotic resistance and virulence genes of Vibrio strains isolated from ready-to-eat shrimps in Edo and Delta States, Nigeria. METHODS AND RESULTS: A total of 1440 ready-to-eat shrimp samples were obtained from open markets from November 2016 to October 2017 and analysed using standard culture-based procedures. Overall, our result showed that the ready-to-eat shrimp samples had high mean aerobic mesophilic bacterial count between 3·543 and 7·489 log10 CFU per gram. Vibrio cell densities ranged between 0·663 and 6·761 log10 CFU per gram. From the total samples, 1343/1440 (93·3%) were positive for Vibrio species where 120 Vibrio isolates were randomly selected and confirmed using genus- and species-specific PCR approach. The PCR identification revealed the presence of Vibrio parahaemolyticus 46 (38·33%), Vibrio vulnificus 14 (11·67%), Vibrio fluvialis 12 (10%), Vibrio alginolyticus 8 (6·67%), Vibrio cholerae 2 (1·67%), Vibrio mimicus 10 (8·33%), Vibrio harveyi 3 (2·5%) and other Vibrio sp. 25 (20·83%). All Vibrio isolates were sensitive to colistin and gentamycin with varying percentage of resistance to other antibiotics used in the study. Multiple antibiotic-resistant (MAR) index ranged from 0·08 to 0·83. The tcp, tdh and trl virulence genes were identified in 95 (79·2%), 92 (76·7%) and 95 (79·2%) of the examined isolates respectively. Antibiotic-resistant genes also revealed the presence of class 1 integrase 75 (62·5%), sul2 87 (72·5%), strB 94 (78·3%) and catB3 68 (56·7%). CONCLUSION: Our findings revealed that the ready-to-eat shrimps may serve as potential reservoirs and medium in the dissemination of prospective MAR pathogens to the consumers and thus constitute a potential risk to public health. SIGNIFICANCE AND IMPACT OF THE STUDY: The findings from this study represent the first comprehensive report of Vibrio isolates from ready-to-eat shrimps in Edo and Delta States, Nigeria. Incessant monitoring of Vibrio strains and their predisposition to antimicrobials is a necessity to guarantee seafood safety and guarantee the best treatment regimen for patients with gastroenteritis.


Assuntos
Resistência Microbiana a Medicamentos/genética , Frutos do Mar/microbiologia , Vibrio/isolamento & purificação , Fatores de Virulência/genética , Animais , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Genes Bacterianos , Testes de Sensibilidade Microbiana , Nigéria , Vibrio/efeitos dos fármacos , Vibrio/genética , Vibrio/patogenicidade
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 230: 118103, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-32000058

RESUMO

An aptamer-based sensitive method was developed here for detection of multiple foodborne pathogens in food matrix by surface-enhanced Raman scattering (SERS) technology. Polydimethylsiloxane (PDMS) film was first prepared and then coated with gold nanoparticles (AuNP) to act as an active substrate for the enhancement of Raman scattering. The as-prepared Au-PDMS film was functionalized with specific pathogen aptamers (Apt) to capture the targets. In addition, aptamers functionalized AuNP integrated with Raman reporters (4-Mercaptobenzoic acid (4-MBA)/Nile blue A (NBA)) were fabricated as pathogen-specific SERS probes. In this scheme, pathogens were first captured by Apt-Au-PDMS film and then bind with SERS probes to allow the formation of a sandwich assay to complete the sensor module for the detection of multiple pathogens. With Vibrio parahaemolyticus and Salmonella typhimurium as model targets, this protocol can selectively detect 18 cfu/mL and 27 cfu/mL, respectively. Furthermore, this platform can be successfully applied to detect pathogens in seafood samples with recoveries ranging from 82.9% to 95.1%.


Assuntos
Aptâmeros de Nucleotídeos/química , Dimetilpolisiloxanos/química , Ouro/química , Nanopartículas Metálicas/química , Salmonella typhimurium/isolamento & purificação , Análise Espectral Raman/métodos , Vibrio/isolamento & purificação , Técnicas Biossensoriais , Limite de Detecção , Salmonella typhimurium/química , Salmonella typhimurium/patogenicidade , Vibrio/química , Vibrio/patogenicidade
14.
Int J Syst Evol Microbiol ; 70(2): 889-896, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31702534

RESUMO

Two Gram-staining-negative, facultatively anaerobic, motile, short clavate and flagellated marine bacteria, designated strains BEI233T and LJC006T, were isolated from the East China Sea. On the basis of the results of 16S rRNA gene sequencing and multilocus sequence analysis, BEI233T and LJC006T should be assigned to the genus Vibrio. The closest phylogenetic relatives of BEI233T are Vibrio scophthalmi LMG 19158T (98.7 % 16S rRNA gene sequence pairwise similarity), Vibrio ichthyoenteri DSM 14397T (98.5 %), Vibrio renipiscarius KCTC 42287T (97.7 %), Vibrio aestuarianus ATCC 35048T (97.3 %) and Vibrio thalassae MD16T (96.5 %), whereas for LJC006T they were Vibrio furnissii CAIM 518T (97.1 %), Vibrio fluvialis LMG 7894T (97.0%), Vibrio tritonius JCM 16456T (96.9 %) and Vibrio xuii LMG 21346T (96.1 %). The growth of BEI233T occurred at 10-37 °C, pH 5.0-8.0 and with 1-7 % (w/v) NaCl, while the growth of LJC006T occurred at 10-37 °C, pH 6.0-9.0, and 0-8 % (w/v) NaCl. The predominant fatty acids (>10 %) were summed feature 3 (C16 : 1ω7c or/and C16 : 1ω6c), C16 : 0 and summed feature 8 (C18 : 1ω7c or/and C18 : 1ω6c), with different proportions. The DNA G+C contents of BEI233T and LJC006T are 42.41 mol% and 41.88 mol%, respectively. On the basis of the results of polyphasic analysis, BEI233T and LJC006T are considered to represent novel species of the genus Vibrio, for which the names Vibrio sinensis sp. nov. and Vibrio viridaestus sp. nov. are proposed. The type strains are BEI233T (=JCM 32692T=KCTC 62618T) and LJC006T (=JCM 32693T=KCTC 62620T), respectively.


Assuntos
Filogenia , Água do Mar/microbiologia , Vibrio/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vibrio/isolamento & purificação
15.
Int J Syst Evol Microbiol ; 70(1): 172-179, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31622230

RESUMO

Two Gram-stain-negative, catalase- and oxidase-positive, facultative anaerobic and rod-shaped motile bacteria, designated strains BEI176T and BEI207T, were isolated from seawater collected in the East China Sea. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains BEI176T and BEI207T belonged to the genus Vibrio and were closely related to each other with 98.18 % similarity. The closest phylogenetic relatives of strain BEI176T were Vibrio alginolyticus LMG 4409T (98.85 %) and Vibrio campbellii LMG 11216T (98.81 %), whereas the closest relative of strain BEI207T was Vibrio hepatarius LMG 20362T (98.64 %). The two strains showed growth at different conditions; while strain BEI176T grew at 16-37 °C, pH 5.0-9.5 and 0-7.0 % (w/v) NaCl, the growth of strain BEI207T occurred at 10-37 °C, pH 6.0-9.5 and 1.0-7.0 % (w/v) NaCl. Both strains shared the same major fatty acid components of summed feature 3 (C16 : 1ω7c or C16 : 1ω6c), C16 : 0 and summed feature 8 (C18 : 1ω6c or C18 : 1ω7c). The DNA G+C contents of the assembled genomic sequences were 44.73 and 45.06 mol% for strains BEI176T and BEI207T, respectively. Average nucleotide identity values between the two strains and their reference species were lower than the threshold for species delineation (95-96 %); in silico DNA-DNA hybridization further showed that the two strains had less than 70 % similarity to their relatives. Therefore, two novel Vibrio species are proposed to accommodate them: Vibrioouci sp. nov. (type strain, BEI176T=MCCC 1K03515T=JCM 32690T= KCTC 62616T) and Vibrioaquaticus sp. nov. (type strain, BEI207T=MCCC 1K03516T=JCM 32691T=KCTC 62617T).


Assuntos
Filogenia , Água do Mar/microbiologia , Vibrio/classificação , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vibrio/isolamento & purificação
16.
J Food Prot ; 82(12): 2094-2099, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31724880

RESUMO

Seafood has frequently been associated with foodborne illness because pathogens are easily introduced during seafood cultivation, handling, and processing. Vibrio parahaemolyticus and Vibrio cholerae are human pathogens that cause gastroenteritis and cholera, respectively, and Vibrio vulnificus can cause fatal wound infections and septicemia. However, information about the occurrence of these pathogens in oysters from the Pacific coast of Mexico is limited to V. parahaemolyticus. In the present study, we evaluated the presence and abundance of these three Vibrio species in 68 raw oysters (Crassostrea corteziensis) obtained from retail seafood markets in Sinaloa, Mexico. The most probable number (MPN)-PCR assay was used for amplification of the tlh (thermolabile hemolysin), ompW (outer membrane protein), and vvhA (hemolytic cytolysin) genes that are specific to V. parahaemolyticus, V. cholerae, and V. vulnificus, respectively. All oyster samples were positive for at least one Vibrio species. V. parahaemolyticus, V. cholerae, and V. vulnificus prevalences were 77.9, 8.8, and 32.3% overall, respectively, and most species were present in all sample periods with increased prevalence in period 3. The tdh (thermostable direct hemolysin) gene was detected in 30.1%, trh (TDH-related hemolysin) was detected in 3.7%, and tdh/trh was detected in 7.5% of the total tlh-positive samples (53 of 68), whereas the pandemic serotype O3:K6 (orf8 positive) was detected in only 1 sample (1.8%). The total prevalence of tdh and/or trh was 41.5%. In none of the samples positive for V. cholerae were the cholera toxin (ctxA) and cholix (chxA) toxigenic genes or the rfb gene encoding the O1 and O139 antigens amplified, suggesting the presence of non-O1 non-O139 V. cholerae strains. Our results clearly indicated a high prevalence of pathogenic Vibrio species in raw oysters from retail seafood markets in Mexico. Consumption of these raw oysters carries the potential risk of foodborne illness, which can be limited by cooking.


Assuntos
Microbiologia de Alimentos , Ostreidae , Alimentos Crus , Vibrio , Animais , Carga Bacteriana , México , Ostreidae/microbiologia , Alimentos Crus/microbiologia , Alimentos Marinhos/microbiologia , Vibrio/isolamento & purificação , Vibrio/fisiologia , Vibrio cholerae , Vibrio parahaemolyticus , Vibrio vulnificus
17.
J Food Prot ; 82(11): 1851-1856, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31603702

RESUMO

In this study, we investigated the occurrence, seasonal distribution, and molecular characterization of pathogenic vibrios in Mediterranean mussels (Mytilus galloprovincialis) and grooved carpet shells (Ruditapes decussatus) from two harvesting areas of Sardinia (Italy). Samples collected before and after depuration were submitted for qualitative and quantitative determination of Vibrio spp. Vibrio spp. isolates were presumptively identified by means of biochemical methods. Identification and virulence profile of Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus were performed by molecular methods. The prevalence of Vibrio spp. in M. galloprovincialis and R. decussatus was, respectively, 96 and 77%. The averaged enumeration (mean ± standard deviation) of Vibrio spp. in samples of M. galloprovincialis and R. decussatus collected at the harvesting time was 2.04 ± 0.45 and 2.51 ± 0.65 log CFU/g, respectively. The average contamination levels in samples collected after purification were 2.28 ± 0.58 log CFU/g (M. galloprovincialis) and 2.12 ± 0.67 log CFU/g (R. decussatus). Four potentially pathogenic V. parahaemolyticus isolates (tdh+ or trh+) were recovered from grooved carpet shells samples. No isolate was tdh+/trh+. The presence of potentially pathogenic vibrios in Sardinian waters strengthens the need for rational purification practices under controlled conditions to guarantee the protection of consumers.


Assuntos
Bivalves , Estações do Ano , Vibrio , Animais , Bivalves/microbiologia , Demografia , Itália , Mytilus/microbiologia , Frutos do Mar/microbiologia , Vibrio/genética , Vibrio/isolamento & purificação , Vibrio cholerae , Vibrio parahaemolyticus , Vibrio vulnificus
18.
BMC Res Notes ; 12(1): 699, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655628

RESUMO

OBJECTIVES: The present study aims to investigate the etiology, clinical profile and resistance pattern of the isolated pathogens in Nepalese adults with acute gastroenteritis. This cross-sectional study was conducted at Sukraraj Tropical and Infectious Disease Hospital, from April 2016 to Sep 2017. Subjects' ages 14 or above, presenting with gastroenteritis with positive stool culture were enrolled for analysis. RESULTS: Of total 153 patients, 47.72% subjects confirmed the presence of bacterial infection. Vibrio cholerae spp and Shigella spp were detected in 36.6% and 23.28% respectively. The most common resistance among Vibrio cholerae was to nitrofurantoin (92.8%), cotrimoxazole (92.8%) and nalidixic acid (92.8%). Among 17 isolates of Shigella spp, the most frequent drug resistant was observed in ampicillin (64.7%), nalidixic acid (58.8%), ceftriaxone (47%). Chloramphenicol (94.1%), tetracycline (88.2%), and cotrimoxazole (82.3%) were found to be the most sensitive towards this pathogen. High rate of diarrhea due to bacterial infection, especially Shigella spp and Vibrio spp and their high rate of drug resistance emphasize an urgent need of designing a surveillance system for antimicrobial resistance in Nepalese setting.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Gastroenterite/complicações , Shigella/efeitos dos fármacos , Centros de Atenção Terciária , Vibrio/efeitos dos fármacos , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/complicações , Infecções Bacterianas/microbiologia , Estudos Transversais , Diarreia/epidemiologia , Diarreia/etiologia , Diarreia/microbiologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Nepal/epidemiologia , Shigella/isolamento & purificação , Vibrio/isolamento & purificação , Adulto Jovem
19.
Mar Pollut Bull ; 149: 110548, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31550576

RESUMO

The present study is aimed to monitoring the ecological indicator and pathogenic microorganism diversity in pilgrimage places beach sand on the Bay of Bengal coast. The samples were collected from three locations and four different sites, and were analyzed by following standard methods. The results clearly indicates, ritual activities were highly contaminated in the beach sand qualities, and exceeded with the standard permissible limit of WHO, USEPA, EU, CPCB beach sand recreational and other contacts activities including pH (11%), TBC (100%), TCB (97%), FCB (88%), TEB (75%), E. coli (75%), disease-causing possible level of Klebsiella (84%), Shigella (75%), Salmonella (63%) and Vibrio (56%). The statistical tools were applied to find the strong evidence. The current study pointed out the major effects on the diffusion of potentially pathogenic microorganisms along the shoreline provided useful information for the setup of measures for public health protection in the Bay of Bengal coast.


Assuntos
Praias , Baías/microbiologia , Comportamento Ritualístico , Indicadores Ambientais , Monitoramento Biológico/métodos , Enterobacteriaceae/isolamento & purificação , Escherichia coli/isolamento & purificação , Humanos , Índia , Klebsiella/isolamento & purificação , Salmonella/isolamento & purificação , Shigella/isolamento & purificação , Vibrio/isolamento & purificação , Microbiologia da Água
20.
J Invertebr Pathol ; 167: 107246, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31521726

RESUMO

In May and June 2015, moderate and severe lesions were observed in Litopenaeus vannamei reared in clear seawater while, at the same time, lesions in shrimp reared in biofloc were considerably fewer. The signs of disease included anorexia, lethargy, melanization, expanded chromatophores, luminescence and necrotic areas in the uropods, suggesting a possible vibriosis. However, lesions observed in shrimp reared in biofloc disappeared after a certain time and without mortality in tanks, whereas mortality and severe signs continued to be observed in shrimp reared in clear seawater. To treat the possible vibriosis, oxytetracycline was administered only in clear seawater tanks, but the results were not successful. Bacterial cultures from hepatopancreas tissues of shrimp from both rearing systems confirmed a vibriosis outbreak only in the clear seawater system. Subsequently, Vibrio harveyi, Vibrio rotiferianus, Photobacterium sp. and Photobacterium damselae were identified from bacterial culture previously isolated for both rearing systems by molecular methods. Shewanella sp. was isolated and identified only in biofloc. To understand the possible pathogenicity and resistance mechanisms of the Vibiro strains for both rearing systems, pathogenicity (toxR) and oxytetracycline resistance-related genes (tet(B), tet(D), tet(G)) were determined. Although these genes were expressed for both rearing systems, biofloc proved to have the ability to control the development of the disease, in comparison to clear water, where the vibriosis was evident regardless of the administration of oxytetracycline as a treatment.


Assuntos
Penaeidae/microbiologia , Resistência a Tetraciclina/genética , Vibrioses/tratamento farmacológico , Vibrio/patogenicidade , Animais , Aquicultura/métodos , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Surtos de Doenças , Genes Bacterianos , Oxitetraciclina/uso terapêutico , Photobacterium/isolamento & purificação , Shewanella/isolamento & purificação , Fatores de Transcrição/genética , Vibrio/efeitos dos fármacos , Vibrio/genética , Vibrio/isolamento & purificação , Virulência/genética , Qualidade da Água
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...