RESUMO
The bacterium strain Cetobacterium sp. C33 was isolated from the intestinal microbial content of Nile tilapia (O. niloticus) under anaerobic conditions. Given that Cetobacterium species are recognized as primary constituents of the intestinal microbiota in cultured Nile tilapia by culture-independent techniques, the adaptability of the C33 strain to the host gastrointestinal conditions, its antibacterial activity against aquaculture bacterial and its antibiotic susceptibility were assessed. The genome of C33 was sequenced, assembled, annotated, and subjected to functional inference, particularly regarding pinpointed probiotic activities. Furthermore, phylogenomic comparative analyses were performed including closely reported strains/species relatives. Comparative genomics with closely related species disclosed that the isolate is not phylogenetically identical to other Cetobacterium species, displaying an approximately 5% sequence divergence from C. somerae and a 13% sequence divergence from Cetobacterium ceti. It can be distinguished from other species through physiological and biochemical criteria. Whole-genome annotation highlighted that Cetobacterium sp. nov. C33 possesses a set of genes that may contribute to antagonism against competing bacteria and has specific symbiotic adaptations in fish. Additional in vivo experiments should be carried out to verify favorable features, reinforcing its potential as a probiotic bacterium.
RESUMO
The probiotic potential of a designed bacterial consortia isolated from a competitive exclusion culture originally obtained from the intestinal contents of tilapia juveniles were evaluated on Nile tilapia alevins. The growth performance, intestinal histology, microbiota effects, resistance to Streptococcus agalactiae challenge, and immune response were assessed. In addition, the following treatments were included in a commercial feed: A12+M4+M10 (Lactococcus lactis A12, Priestia megaterium M4, and Priestia sp. M10), M4+M10 (P. megaterium M4, and Priestia sp. M10) and the single bacteria as controls; A12 (L. lactis A12), M4 (P. megaterium M4), M10 (Priestia sp. M10), also a commercial feed without any probiotic addition was included as a control. The results showed that all probiotic treatments improved the growth performance, intestinal histology, and resistance during experimental infection with S. agalactiae in comparison to the control fish. Also, the administration of probiotics resulted in the modulation of genes associated with the innate and adaptive immune systems that were non-dependent on microbial colonization. Surprisingly, L. lactis A12 alone induced benefits in fish compared to the microbial consortia, showing the highest increase in growth rate, survival during experimental infection with S. agalactiae, increased intestinal fold length, and the number of differentially expressed genes. Lastly, we conclude that a competitive exclusion culture is a reliable source of probiotics, and monostrain L. lactis A12 has comparable or even greater probiotic potential than the bacterial consortia.
Assuntos
Ciclídeos , Doenças dos Peixes , Microbioma Gastrointestinal , Probióticos , Tilápia , Animais , Probióticos/farmacologia , Dieta/veterinária , Ração Animal/análise , Suplementos NutricionaisRESUMO
This study aims to mine a previously developed continuous-flow competitive exclusion culture (CFCEC) originating from the Tilapia gut microbiome as a rational and efficient autochthonous probiotic strain recovery source. Three isolated strains were tested on their adaptability to host gastrointestinal conditions, their antibacterial activities against aquaculture bacterial pathogens, and their antibiotic susceptibility patterns. Their genomes were fully sequenced, assembled, annotated, and relevant functions inferred, such as those related to pinpointed probiotic activities and phylogenomic comparative analyses to the closer reported strains/species relatives. The strains are possible candidates of novel genus/species taxa inside Lactococcus spp. and Priestia spp. (previously known as Bacillus spp.) These results were consistent with reports on strains inside these phyla exhibiting probiotic features, and the strains we found are expanding their known diversity. Furthermore, their pangenomes showed that these bacteria have indeed a set of so far uncharacterized genes that may play a role in the antagonism to competing strains or specific symbiotic adaptations to the fish host. In conclusion, CFCEC proved to effectively allow the enrichment and further pure culture isolation of strains with probiotic potential.
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Octocorals are among the most prolific sources of biologically active compounds. A significant part of their specialized metabolites richness is linked to the abundance of their associated microbiota. Consequently, research on the bioprospecting potential of microorganisms associated with these marine invertebrates has gained much interest. Here, we describe the draft genome of Gordonia hongkongensis strain EUFUS-Z928 isolated from the octocoral Eunicea fusca. The genome was assembled de novo from short-read whole-genome sequencing data. Additionally, functional annotation of predicted genes was performed using the RAST tool kit, including genome mining for specialized metabolite biosynthetic gene clusters using the antiSMASH v6.0 tool. The genome sequence data of G. hongkongensis EUFUS-Z928 can provide information for further analysis of the potential biotechnological use of this microorganism and guide the characterization of other related actinobacterial isolates. Likewise, this information increases the analytical capacity for studying the genus Gordonia.
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This study reports the characterization of the microbial community composition, and the establishment and dynamics of a continuous-flow competitive exclusion culture (CFCEC) derived from gut microbiomes of Nile tilapia (Oreochromis niloticus) specimens reared on aquaculture farms in Colombia. 16S rRNA gene amplicon Illumina sequencing was used to identify taxonomical changes in the CFCEC microbial community over time. The CFCEC was developed from adult tilapia from two farms in Colombia, and CFCEC samples were collected over two months. The pH varied from 6.25 to 6.35 throughout culturing, while anaerobic and aerobic cell counts stabilized at day 9, at 109 CFU mL-1 and were maintained to day 68. A variation in the CFCEC bacterial composition was observed over time. Cetobacterium was the most abundant in the first two days and coincided with a higher CFCEC supernatant antimicrobial effect against the fish pathogen Streptococcus agalactiae. Antimicrobial activity against S. agalactiae disappeared by day 3. Changes in bacterial composition continued to day 33 with Lactococcus spp. becoming the most abundant member of the community. In conclusion, the study of the CFCEC from intestinal tract of Nile tilapia (Oreochromis niloticus) by 16S rRNA gene sequencing allowed identification of predominant bacterial genera in the continuous-flow competitive exclusion culture exhibiting antibacterial activity against the fish pathogen Streptococcus agalactiae.
Assuntos
Bactérias/classificação , Ciclídeos/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Streptococcus agalactiae/crescimento & desenvolvimento , Animais , Bactérias/isolamento & purificação , Carga Bacteriana , Técnicas Bacteriológicas , Colômbia , Fusobactérias/isolamento & purificação , Fusobactérias/fisiologia , Microbioma Gastrointestinal , Lactococcus/isolamento & purificação , Lactococcus/fisiologia , Viabilidade Microbiana , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Resumen: la tosferina es una enfermedad aguda bacteriana, causada por Bordetellapertussis, que afecta el tracto respiratorio superior, produciendo fuertes accesos de tos, asfixia y cianosis. Otros microorganismos pueden producir un cuadro similar a la tosferina, conocido como síndrome coqueluchoide, el cual es su principal diagnóstico diferencial. La enfermedad se presenta en su mayoría en lactantes menores, especialmente los que no están adecuadamente inmunizadosy están en contacto con adolescentes y adultos, potenciales reservorios de la enfermedad. Actualmente se realiza el diagnóstico mediante criterios clínicos y microbiológicos, que permiten clasificar al paciente en caso probable o confirmado.En cuanto al tratamiento el manejo estándar de la enfermedad incluye antibióticostipo macrólidos. Dependiendo de la severidad del cuadro se implementa tratamiento de soporte con oxígeno, corticoides, vasodilatadores pulmonares y sedantes. La mejor forma de prevención es una alta cobertura de vacunación cumpliendo los esquemas propuestos. La protección inducida por la vacuna alcanzaentre 70%-85% de los títulos de anticuerpos, los cuales disminuyen entre los 4-7 años posvacunación, lo que hace imprescindible la implementación de una dosis de refuerzo a los 18 meses y 5 años. En Colombia todavía falta el establecimiento de otras opciones a edades más avanzadas, previniendo que la persona joven y adulta sea el reservorio de la enfermedad. En general, los hallazgos y avances en el estudio de la tosferina evidencian que es una entidad clínica con un aumento significativo en su incidencia en la población pediátrica, a pesar de que se cree que está totalmente controlada.
Abstract: pertussis is an acute bacterial disease caused by Bordetella pertussis that affects the upper respiratory tract, producing severe cough, asphyxia, and cyanosis. Other microorganisms can cause a similar clinical picture to pertussis, known as coqueluchoide syndrome, which is the main differential diagnosis. The disease occurs mainly in infants, especially those who are not adequately immunizedand are exposed to adolescents and adults, the potential reservoirs of the disease. Currently the diagnosis is by clinical and microbiological criteria for classifying the patient as probable or confirmed case. The treatment standard management is with antibiotic, especially macrolides. Depending on the severity of case, support treatment including oxygen, steroids, sedatives, and pulmonary vasodilators is implemented. The best prevention of disease is high vaccination coverage, fulfilling with the schemes proposed. The induced protection by the vaccine reaches between 70%-85% of antibody titers, which decrease between 4-7 years post vaccination, which make essential to implement a strategy of booster shot at 18 months and 5 years-old. However, Colombia has not developedother options at older ages, that prevent the young and adults become the reservoir of the disease. Overall findings and advances in the whooping cough study shows that is a clinical entity with a significant increase of its incidence in the pediatric population, although it is believed that is fully controlled.
Assuntos
Humanos , Bordetella pertussis , Tosse , Vacina contra Coqueluche , Terapêutica , CoquelucheRESUMO
La presente publicación analiza la disponibilidad, distribución y potencialidad de los recursos físicos en el marco de los recursos de salud, su evolución a través del tiempo, así como sus posibilidades de desarrollo hacia el mejoramiento en cuanto a accesibilidad y cobertura para los sectores menos favorecidos de la población peruana(AU)
Assuntos
Recursos em Saúde , Infraestrutura Sanitária , Diagnóstico da Situação de Saúde , PeruRESUMO
La presente publicación describe información básica que sirve de elemento de juicio para el diseño de un programa sistematizado de mantenimiento de la planta física, instalación y equipos de los establecimientos de salud del Ministerio de Salud(AU)
Assuntos
Recursos em Saúde , Infraestrutura Sanitária , Levantamentos Sanitários sobre Abastecimento de Água , Instalações Sanitárias , PeruRESUMO
La presente publicación analiza la disponibilidad, distribución y potencialidad de los recursos físicos en el marco de los recursos de salud, su evolución a través del tiempo, así como sus posibilidades de desarrollo hacia el mejoramiento en cuanto a accesibilidad y cobertura para los sectores menos favorecidos de la población peruana
Assuntos
Diagnóstico da Situação de Saúde , Infraestrutura Sanitária , Recursos em Saúde , PeruRESUMO
La presente publicación describe información básica que sirve de elemento de juicio para el diseño de un programa sistematizado de mantenimiento de la planta física, instalación y equipos de los establecimientos de salud del Ministerio de Salud
Assuntos
Infraestrutura Sanitária , Instalações Sanitárias , Levantamentos Sanitários sobre Abastecimento de Água , Recursos em Saúde , PeruRESUMO
Financiado por USAID bajo acuerdo de Cooperacion N0. 527-0167-CA-00-5054-00 con la Research Foundation of the State University of New York; Publicado con la cooperacion de la Organizacion Panamericana de la Salud