Project description:Although the biodegradation of biodegradable plastics in soil and compost is well-studied, there is little knowledge on the metabolic mechanisms of synthetic polymers degradation by marine microorganisms. Here, we present a multiomics study to elucidate the biodegradation mechanism of a commercial aromatic-aliphatic copolyester film by a marine microbial enrichment culture. The plastic film and each monomer can be used as sole carbon source. Our analysis showed that the consortium synergistically degrades the polymer, different degradation steps being performed by different members of the community. Analysis of gene expression and translation profiles revealed that the relevant degradation processes in the marine consortium are closely related to poly(ethylene terephthalate) biodegradation from terrestrial microbes. Although there are multiple genes and organisms with the potential to perform a degradation step, only a few of these are active during biodegradation. Our results elucidate the potential of marine microorganisms to mineralize biodegradable plastic polymers and describe the mechanisms of labor division within the community to get maximum energetic yield from a complex synthetic substrate.
Project description:Wastewater treatment plants (WWTPs) and Drinking water treatment plants (DWTPs) are critical points for public health for persistently remaining microorganisms after treatment may pose a risk. This study aimed to conduct microbial metagenomic analyses on waters from both DWTPs and WWTPs under the Istanbul Water and Sewerage Administration (ISKI). In this study a total of 52 samples were included, comprising 18 samples from DWTPs and 34 from WWTPs. All water samples underwent pre-isolation filtration. DNA isolation was conducted using filter material, followed by library preparation and sequencing on a NovaSeq 6000 instrument following the manufacturer's guidelines.
Project description:Polylactic acid (PLA) is a promising biodegradable material used in various fields, such as mulching films and disposable packaging materials. Biological approaches for completely degrading biodegradable polymers can provide environmentally friendly solutions. However, to our knowledge, no studies have performed transcriptome profiling to analyze PLA-degrading genes of PLA-degrading bacteria. Therefore, this study reports for the first time an RNA sequence approach for tracing genes involved in PLA biodegradation in the PLA-degrading bacterium Brevibacillus brevis. In the interpretation results of the differentially expressed genes, the hydrolase genes mhqD and nap and the serine protease gene besA were up-regulated by a fold change of 7.97, 4.89, and 4.09, respectively. This result suggests that hydrolases play a key role in PLA biodegradation by B. brevis. In addition, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses showed that genes implicated in biofilm formation were upregulated. The biodegradation of PLA starts with bacteria attaching to the surface of PLA and forming a biofilm. Therefore, it could be confirmed that the above genes were up-regulated for access to PLA and biodegradation. Our results provide transcriptome-based insights into PLA biodegradation, which pitch a better understanding of microbial biodegradation of plastics.
Project description:Wastewater-based epidemiology has been revealed as a powerful approach for the survey of the population's health and lifestyle. In this context, proteins have been proposed as potential biomarkers that complement the information provided by those used up to now (small exogenous molecules, metabolites, and genomic material). However, few is known about the range of molecular species and dynamics of proteins in wastewater and the information hidden in these protein profiles is still to be uncovered. In previous research, we have described for the first time the proteome of wastewater using polymer probes immersed in wastewater at the entrance of a wastewater treatment plant (WWTP). Here, we studied the protein composition of wastewater from municipalities with diverse population and industrial activities. For this purpose, we collected water samples at the inlet of 10 different WWTPs in Catalonia at three different times of the year and the soluble fraction of this material was then analyzed by Liquid Chromatography High-resolution Tandem Mass Spectrometry using a shotgun proteomics approach. The complete proteomic profiles, the distribution among different organisms, and the semiquantitative analysis of the main constituents are described. Excreta (urine and feces) from humans, and blood and other residues from livestock were identified as the two main protein sources. Significant differences between the proteomes in the soluble phase and the particulate material, respectively dominated by eukaryote and bacterial proteins, were observed. Our findings provide new insights into the characterization of wastewater proteomics that allow proposing specific bioindicators for wastewater-based environmental monitoring, including human and animal population monitoring, most notably, for rodent pest control (immunoglobulins, amylases), and livestock processing industry monitoring (albumins).
Project description:protein based stable isotope probing was performed for identifying microorganisms actually responsible for biphenyl biodegradation in soil environment.
Project description:In this study, we exposed Caenorhabditis elegans wild types N2 to water collected from six sources in the Dutch village Sneek. The sources were: wastewater from a hospital, a community (80 households), a nursing home, influent into the local municipal wastewater treatment plant, effluent of the wastewater treatment plant, and surface water samples. The goal of the experiment was to determine if C. elegans can be used to identify pollutants in the water by transcriptional profiling. Age synchronized worms at developmental L4 larval stage were exposed to treatment for 24 hours. After flash freezing the samples, RNA was isolated, labeled and hybridized on oligo microarray (Agilent) slides.
Project description:Three surface waters in Gainesville, Florida were used in a 48 hour whole effluents exposure to assess gene expression profiles of male fathead minnow liver. Microarray analysis was used to determine changes in gene expression of exposed fish to waters from a site downstream of a wastewater treatment plant (streamwater), a wastewater treatment plant (wastewater), and a lake (stormwater). Differences in gene expression between fish exposed to collected waters and controls were observed. Number of altered genes and biological processes were 1028 and 18 for stormwater; 787 and 19 for streamwater; and: 575 and 12 for wastewater. In general, the effects observed in all exposed fish were related with fatty acid metabolism, DNA repair, oxidation-reduction process, cell wall catabolic process and apoptosis. All exposed fish showed altered expression of genes related with DNA damage repair. In particular fish exposed to stormwater and streamwater showed downregulation of several key intermediates transcripts of cholesterol. The presence and environmental persistence of perfluorinated chemicals (PFCs) in these waters, the resemblance in known effects on transcripts with those found in this study, suggest that the set of genes differentially regulated in fathead minnows after 48 hours of exposure may be attributed to exposure to PFCs. Three surface water sites were chosen for effluent collection in Gainesville, Florida: A lake (stormwater), surface water downstream of a wastewater treatment plant (streamwater), and a wastewater treatment plant effluent used for landscaping irrigation (wastewater). Water from each site was collected two days prior to the fish exposure experiment using Chemfluor ® tubing and a 120 liters steel barrels coated with polyester resin (gel coat) to avoid cross-contamination. Three barrels for each effluent were collected during day 1. Water from the barrel was transported to the laboratory and pumped into four fiberglass cylinders in the aquatic toxicology facility. Water from each cylinder was then pumped into four replicate aquariums per treatment and kept for 1 day without fish (pre-treatment). On day 2, four male fathead minnows from a common tank were transferred to each replicate aquarium and kept for 48 hours, with one 75% water change after first 24 hours. The exposure system consisted of 40 L glass aquaria. Each exposure was conducted in quadruplicate and each aquarium contained the four male fish in 25 L of treatment water . The water used in the control treatment was carbon filtered, dechlorinated tap water. The positions of the treatment tanks were randomized and test initiation times were staggered to ensure an exposure/sampling interval of 48 h. The fish were not fed during the experiment. The temperature range of the water was 24-26 °C with a photoperiod of 16 h light: 8 h dark. Liver was isolate from 4 males indviduals for each treatment except for control group (3 individuals).
Project description:Understanding the bacterial community structure, and their functional analysis for active bioremediation process is essential to design better and cost effective strategies. Microarray analysis enables us to simultaneously study the functional and phylogenetic markers of hundreds of microorganisms which are involved in active bioremediation process in an environment. We have previously described development of a hybrid 60-mer multibacterial microarray platform (BiodegPhyloChip) for profiling the bacterial communities and functional genes simultaneously in environments undergoing active bioremediation process (Pathak et al; Appl Microbiol Biotechnol,Vol. 90, 1739-1754). The present study involved profiling the status of bacterial communities and functional (biodegradation) genes using the developed 60-mer oligonucleotide microarray BiodegPhyloChip at five contaminated hotspots in the state of Gujarat, in western India. The expression pattern of functional genes (coding for key enzymes in active bioremediation process) at these sites was studied to understand the dynamics of biodegradation in the presence of diverse group of chemicals. The results indicated that the nature of pollutants and their abundance greatly influence the structure of bacterial communities and the extent of expression of genes involved in various biodegradation pathways. In addition, site specific factors also play a pivotal role to affect the microbial community structure as was evident from results of 16S rRNA gene profiling of the five contaminated sites, where the community structure varied from one site to another drastically.
Project description:The ability of Microlunatus phosphovorus to accumulate large amounts of polyphosphate (Poly-P) plays an important role in removing soluble phosphorus from wastewater. Our analyses indicate that Microlunatus phosphovorus accumulates Poly-P under aerobic conditions but releases phosphorus under anaerobic conditions. To determine the mechanisms underlying Poly-P metabolism, we compared transcriptional profiles under aerobic and anaerobic conditions. Significant differences were detected in the expression levels of genes associated with Poly-P metabolism between aerobic and anaerobic conditions. These findings enhance our understanding of phosphate metabolism in a major bacterial species involved in wastewater phosphorus reduction.
Project description:Membrane proteins can be examined in near-native lipid-bilayer environments with the advent of polymer-encapsulated nanodiscs. These nanodiscs self-assemble directly from cellular membranes, allowing in vitro probing of membrane proteins with techniques that had previously been restricted to soluble or detergent-solubilized proteins. Nonetheless, the high charge densities of existing polymers obstruct bioanalytical and preparative techniques through unspecific interactions. Here we describe a simple strategy for producing water-soluble, electroneutral polymer nanodiscs. Through attachment of a sulfobetaine group, the commercial polymers DIBMA and SMA can be easily converted into the charge-neutral maleimide derivatives, sulf DIBMA and sulf SMA, which readily extract proteins and phospholipids from artificial and cellular membranes to form nanodiscs. Crucially, the electroneutrality of the new nanodiscs averts unspecific interactions, thereby enabling reliable lab-on-a-chip detection of protein/lipid interactions and in vitro translation of membrane proteins. Finally, we create a library containing thousands of human membrane proteins and use proteome profiling by mass spectrometry to show the preservation of protein complexes in electroneutral nanodiscs.