Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1268142 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Marine bacteria isolated from Sargassum ilicifolium macroalgae
| PRJNA1223677 | ENA
Project description:Macroalgae contribute substantially to primary production in coastal ecosystems. Their biomass, mainly consisting of polysaccharides, is cycled into the environment by marine heterotrophic bacteria (MHB), using largely uncharacterized mechanisms. In Zobellia galactanivorans, we discovered and characterized the complete catabolic pathway for carrageenans, major cell wall polysaccharides of red macroalgae, providing a model system for carrageenan utilization by MHB. We further demonstrate that carrageenan catabolism relies on a multifaceted carrageenan-induced regulon, including a non-canonical polysaccharide utilization locus (PUL) and several distal genes. The genetic structure of the carrageenan utilization system is well conserved in marine Bacteroidetes, but modified in other MHB phyla. The core system is completed by additional functions which can be assumed by non-orthologous genes in different species. This complex genetic structure is due to multiple evolutionary events including gene duplications and horizontal gene transfers. These results allow for an extension on the definition of bacterial PUL-mediated polysaccharide digestion.
2017-12-06 | GSE101142 | GEO
Project description:We cultivated the flavobacterium Zobellia galactanivorans DsijT with fresh brown macroalgae with distinct chemical compositions. Its capacity to use macroalgae as the sole carbon source via the secretion of extracellular enzymes, leading to extensive tissue damages, highlights a sharing pioneer degrader behavior. RNA-seq transcriptome analysis revealed a metabolic shift toward the utilization of brown algal polysaccharides during tissue degradation. A subset of genes was specifically induced in cells grown with intact algae compared to purified polysaccharides. It notably includes genes involved in protection against oxidative burst, type IX secretion system proteins and novel uncharacterized Polysaccharides Utilization Loci (PULs). Comparative growth experiments and genomics between Zobellia members brought out putative genetic determinants of the pioneer behavior of Z. galactanivorans, whose in vitro role could be further characterized. This work constitutes the first investigation of the metabolic mechanisms of bacteria mediating fresh macroalgae breakdown, and will help unravel the role of marine microbes in the fate of macroalgal biomass.
2022-07-27 | GSE189322 | GEO
Project description:Zero-valent sulfur (ZVS) and thiosulfate are important intermediates in the biogeochemical cycle of sulfur. The former has been proved to be existed in the cold seep and hydrothermal systems. Three thiosulfate oxidation pathways are already identified and here we found a novel one in Erythrobacter, which was the first genus in the family Erythrobacteraceae that could accumulate ZVS during thiosulfate oxidation. Erythrobacter flavus 21-3 was isolated from the sediment of clod seep. Genomic analyses showed the typical genes encoding Sox multienzyme complex were absent in the genome of E. flavus 21-3. Through proteome and genome data, we identified a three gene involved pathway of thiosulfate oxidation, including thiosulfate dehydrogenase (tsdA), thiosulfohydrolase (soxB) and sulfur dioxygenases (sdo). For the first time, genetic operating system was constructed in Erythrobacter, and mutant strains ΔtsdA, ΔsoxB, ΔsdoA, ΔsdoB and ΔsdoAB were constructed. Stoichiometry was calculated and tetrathionate and ZVS were found to be the intermediates in this novel thiosulfate oxidation pathway. The diverse and distribution of these proteins were investigated and this novel thiosulfate oxidation pathway may exist in bacteria formerly ignored the function of ZVS production. The results give a powerful evidence for a new source of biogenetic ZVS in cold seep.
2021-09-09 | PXD016502 | Pride
Project description:Marine cyanobacteria are thought to be the most sensitive of the phytoplankton groups to copper toxicity, yet little is known of the transcriptional response of marine Synechococcus to copper shock. Global transcriptional response to two levels of copper shock was assayed in both a coastal and an open ocean strain of marine Synechococcus using whole genome expression microarrays. Both strains showed an osmoregulatory-like response, perhaps as a result of increasing membrane permeability. This could have implications for marine carbon cycling if copper shock leads to dissolved organic carbon leakage in Synechococcus. The two strains additionally showed a reduction in photosynthetic gene transcripts. Contrastingly, the open ocean strain showed a typical stress response whereas the coastal strain exhibited a more specific oxidative or heavy metal type response. In addition, the coastal strain activated more regulatory elements and transporters, many of which are not conserved in other marine Synechococcus strains and may have been acquired by horizontal gene transfer. Thus, tolerance to copper shock in some marine Synechococcus may in part be a result of an increased ability to sense and respond in a more specialized manner.
2009-07-01 | GSE13910 | GEO
Project description:Six Vibrio strains isolated from distinct marine sources
| PRJNA1190303 | ENA
Project description:Brown macroalgae holds an enormous potential as a future feedstock because it rapidly forms large biomasses and has high carbohydrate content (35% of its dry weight consists of alginate and mannitol). However, utilization of brown macroalgae by conventional microbial platforms (e.g., Escherichia coli and Saccharomyces cerevisiae) has been limited due to the inability of these platforms to metabolize alginate. Although recent studies engineered them to utilize alginate, their growth rates and metabolic activities are still too low for industrial applications, likely due to the unoptimized expression of multiple xenogeneic genes. Here, we isolated Vibrio sp. dhg, a novel, fast-growing bacterium that has been naturally evolved for efficient alginate assimilation (growth rate = 0.98 h-1). Especially, both the growth rate and sugar uptake rate of V. sp. dhg are substantially higher than the rates of E. coli for most biomass-derivable sugars. Based on our systematic characterization of its metabolism and gene expression architecture, we were able to develop a genetic toolbox for its engineering. By using this microorganism, we successfully demonstrated its ability to produce a broad spectrum of chemicals from alginate-mannitol mixtures with high productivities (1.1 g ethanol/L/h, 1.3 g 2,3-butanediol and acetoin/L/h, and 0.69 mg lycopene/L/h). Collectively, the V. sp. dhg strain is a powerful platform for the conversion of brown macroalgae sugars whose usage will dramatically accelerate the production of value-added biochemicals in the future.
2019-05-02 | GSE119357 | GEO
Project description:Proteomic analysis of iron restriction of the marine pathogen Renibacterium salmoninarum that causes the disease (BKD), in this study two isolated Chilean H-2 strains and the type strain ATCC33209 have been used. These results show that changes are generated at the level of protein expression in pathways involved in iron metabolism and uptake.
2021-11-29 | PXD024459 | Pride