Ontology highlight
ABSTRACT:
PROVIDER: PRJNA439215 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Integrons are genetic elements that enable bacterial adaptation by collecting new genes encoded in integron cassettes (ICs) to create a reservoir of adaptive functions. These cassettes typically lack their own promoters and rely on the integron platform for their expression. Integrons, well-known for spreading antibiotic resistance genes in clinically relevant Gram-negative species, include Mobile Integrons (MIs), that transport over 170 resistance genes. In contrast, Sedentary Chromosomal Integrons (SCIs), ubiquitous in Vibrio species, are primarily found within bacterial chromosomes. However, their functions are not related to antimicrobial resistance and are largely unexplored. SCIs, typified by the Superintegron (SI) in Vibrio cholerae, represent ancient and highly variable regions in bacterial genomes. The SI is extensive, housing 179 integron cassettes, mostly with unknown functions. Although 19 cassettes encode toxin-antitoxin (TA) systems, which stabilize the array, the intricacies of the SI are challenging to study due to its size and unique integrase. To investigate the SI's impact on V. cholerae, we developed the SeqDelTA approach, enabling the gradual deletion of the SI. This deletion facilitates the use of standard genetic tools without SI interference. Our in-depth analysis of the resulting ∆SI strain, covering various aspects, demonstrated no significant alterations in V. cholerae's physiology. Despite their extended coevolution, SCIs appear to be genetically isolated from the host genome.
2023-11-23 | GSE247496 | GEO
Project description:Integrons are genetic platforms that acquire new genes encoded in integron cassettes (ICs), building arrays of adaptive functions for bacteria. ICs generally encode promoterless genes, whose expression relies on the PC promoter within the integron platform. Cassette arrays are assumed to be operon-like structures in which expression is dependent on the distance to the Pc. This is especially relevant in large sedentary chromosomal integrons (SCIs,) like the ones in Vibrio species. We have identified 29 gene-less cassettes in 4 Vibrio SCIs, and explored whether their function could be related to regulating the transcription of adjacent ICs. We show that most gene-less cassettes have promoter activity on the sense strand, enhancing the expression of downstream cassettes. Accordingly, we found that most of the superintegron in Vibrio cholerae is not silent. These promoter cassettes can trigger the expression of a silent dfrB9 resistance cassette downstream, increasing trimethoprim resistance >512-fold in V. cholerae and Escherichia coli. Additionally, one cassette had an antisense promoter capable of reducing trimethoprim resistance through transcriptional interference. Our findings highlight the regulatory role of gene-less cassettes in the expression of adjacent cassettes, emphasizing their significance in large SCIs and their clinical importance if captured by mobile integrons.
2023-04-17 | GSE229776 | GEO
Project description:Class 1 integron gene cassettes in rivers in Japan
| PRJDB12624 | ENA
Project description:Freshwater environments such as rivers receive effluent discharges from wastewater treatment plants, representing a potential hotspot for antibiotic resistance genes (ARGs). These effluents also contain low levels of different antimicrobials including biocides and antibiotics such as sulfonamides that can be frequently detected in rivers. The impact of such exposure on ARG prevalence and microbial diversity of riverine environment is unknown, so the aim of this study was to investigate the release of a sub-lethal concentration (<4 g L-1) of the sulfonamide compound sulfamethoxazole (SMX) on the river bacterial microbiome using a microflume system. This system was a semi-natural in-vitro microflume using river water (30 L) and sediment, with circulation to mimic river flow. A combination of ‘omics’ approaches were conducted to study the impact of SMX exposure on the microbiomes within the microflumes. Metaproteomics did not show differences in ARGs expression with SMX exposure in water.
2021-07-06 | PXD023822 | Pride
Project description:Characterization of microbial communities at the genomic, transcriptomic, proteomic and metabolomic levels, with a special interest on lipid accumulating bacterial populations, which are naturally enriched in biological wastewater treatment systems and may be harnessed for the conversion of mixed lipid substrates (wastewater) into biodiesel. The project aims to elucidate the genetic blueprints and the functional relevance of specific populations within the community. It focuses on within-population genetic and functional heterogeneity, trying to understand how fine-scale variations contribute to differing lipid accumulating phenotypes. Insights from this project will contribute to the understanding the functioning of microbial ecosystems, and improve optimization and modeling strategies for current and future biological wastewater treatment processes. This project contains datasets derived from the same biological wastewater treatment plant. The data includes metagenomes, metatranscriptomes, metaproteomes and organisms isolated in pure cultures. Characterization of microbial communities at the genomic, transcriptomic, proteomic and metabolomic levels, with a special interest on lipid accumulating bacterial populations, which are naturally enriched in biological wastewater treatment systems and may be harnessed for the conversion of mixed lipid substrates (wastewater) into biodiesel. The project aims to elucidate the genetic blueprints and the functional relevance of specific populations within the community. It focuses on within-population genetic and functional heterogeneity, trying to understand how fine-scale variations contribute to differing lipid accumulating phenotypes. Insights from this project will contribute to the understanding the functioning of microbial ecosystems, and improve optimization and modeling strategies for current and future biological wastewater treatment processes. This project contains datasets derived from the same biological wastewater treatment plant. The data includes metagenomes, metatranscriptomes, metaproteomes and organisms isolated in pure cultures.
2020-08-19 | PXD013655 | Pride
Project description:On March 12, 2020, the World Health Organization (WHO) declared COVID-19 as a global pandemic. COVID-19 is produced by a novel β-coronavirus known as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) [1]. Several studies have detected SARS-CoV-2 RNA in urine, feces, and other biofluids from both symptomatic and asymptomatic people with COVID-19 [2], suggesting that SARS-CoV-2 RNA could be detected in human wastewater [3]. Thus, wastewater-based epidemiology (WBE) is now used as an approach to monitor COVID-19 prevalence in many different places around the world [4-10] . Reverse transcription quantitative polymerase chain reaction (RT-qPCR) is the most common SARS-CoV-2 detection method in WBE, but there are other methods for viral biomolecule detection that could work as well. The aim of this study was to evaluate the presence of SARS-CoV-2 proteins in untreated wastewater (WW) influents collected from six wastewater treatment plants (WWTPs), from Durham Region, Ontario, Canada, using a LC-MS/MS-based proteomics approach. We identified many SARS-CoV-2 proteins in these wastewater samples, with peptides from pp1ab being the most consistently detected and with consistent abundance.
2022-03-31 | PXD026412 | Pride
Project description:Understanding microbial community diversity is thought to be crucial for improving process functioning and stabilities of wastewater treatment systems. However, current studies largely focus on taxonomic groups based on 16S rRNA, which are not necessarily linked to functioning, or a few selected functional genes. Here we launched a study to profile the overall functional genes of microbial communities in three full-scale wastewater treatment systems. Triplicate activated sludge samples from each system were analyzed using a high-throughput metagenomics tool named GeoChip 4.2, resulting in the detection of 38,507 to 40,647 functional genes. A high similarity of 75.5% to 79.7% shared genes was noted among the nine samples. Moreover, correlation analyses showed that the abundances of a wide array of functional genes were associated with system performances. For example, the abundances of overall nitrogen cycling genes had a strong correlation to total nitrogen (TN) removal rates (r = 0.7647, P < 0.01). The abundances of overall carbon cycling genes were moderately correlated with COD removal rates (r = 0.6515, P < 0.01). Lastly, we found that influent chemical oxygen demand (COD inf) and total phosphorus concentrations (TP inf), and dissolved oxygen (DO) concentrations were key environmental factors shaping the overall functional genes. Together, the results revealed vast functional gene diversity and some links between the functional gene compositions and microbe-mediated processes.
2014-12-31 | GSE53744 | GEO
Project description:Manufactured nanomaterials (MNMs) are increasingly incorporated into consumer products that are disposed into sewage. In wastewater treatment, MNMs adsorb to activated sludge biomass where they may impact biological wastewater treatment performance, including nutrient removal. Here, we studied MNM effects on bacterial polyhydroxyalkanoate (PHA), specifically polyhydroxybutyrate (PHB), biosynthesis because of its importance to enhanced biological phosphorus (P) removal (EBPR). Activated sludge was sampled from an anoxic selector of a municipal wastewater treatment plant (WWTP), and PHB-containing bacteria were concentrated by density gradient centrifugation. After starvation to decrease intracellular PHB stores, bacteria were nutritionally augmented to promote PHB biosynthesis while being exposed to either MNMs (TiO2 or Ag) or to Ag salts (each at a concentration of 5 mg L-1). Cellular PHB concentration and PhyloChip community composition were analyzed. The final bacterial community composition differed from activated sludge, demonstrating that laboratory enrichment was selective. Still, PHB was synthesized to near-activated sludge levels. Ag salts altered final bacterial communities, although MNMs did not. PHB biosynthesis was diminished with Ag (salt or MNMs), indicating the potential for Ag-MNMs to physiologically impact EBPR through the effects of dissolved Ag ions on PHB producers.
2014-12-03 | GSE63781 | GEO