Browsing by Author "Henriques, Isabel"
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- Adaptative biological response of aerobic granular sludge to events of single or combined wastewater related stressorsPublication . Alves, Marta; Henriques, Isabel; Castro, Paula M. L.; Amorim, Catarina L.Wastewater comprises various stressors and their individual and combined immediate effects on aerobic granular sludge (AGS) are still underexplored. In this study, the AGS was exposed for 24 hours to wastewater with varying salt concentrations (up to 30 g NaCl L⁻¹) alongside pharmaceuticals (diclofenac, DCF or carbamazepine, CBZ). Differences in extracellular polymeric substances (EPS) production and composition were observed between single and combined stressor exposures. The removal of pharmaceuticals was influenced by the wastewater salinity level and the type of pharmaceutical, with a positive correlation found between the EPS polysaccharides content and the removal efficiency at salinity levels up to 10 g NaCl L⁻¹ . The combination of salinity and pharmaceuticals in wastewater also impacted the AGS bacteriome composition, with the bacteriome of the AGS not-exposed to stressors showing greater similarity to that of AGS exposed to DCF than to that exposed to CBZ, at each wastewater salinity level. Functional profiling suggested that short-term exposure to stressors slightly increased the relative abundance of mismatch repair, cell motility, and homologous recombination functions in the AGS microbiome. Summing up, the stressors impact on AGS bacteriome structure and EPS production varies depending on the pharmaceutical and whether it is combined with salt or not. This study unveiled the immediate AGS response to both single and combined stressors exposure, but a more thoughtful characterization of the bacteriome composition over the early adaptation period to stressors is needed to understand the community succession and to identify key microbial groups.
- Antibiotic resistance in European wastewater treatment plants mirrors the pattern of clinical antibiotic resistance prevalencePublication . Pärnänen, Katariina M. M.; Narciso-da-Rocha, Carlos; Kneis, David; Berendonk, Thomas U.; Cacace, Damiano; Do, Thi Thuy; Elpers, Christian; Fatta-Kassinos, Despo; Henriques, Isabel; Jaeger, Thomas; Karkman, Antti; Martinez, Jose Luis; Michael, Stella G.; Michael-Kordatou, Irene; O’Sullivan, Kristin; Rodriguez-Mozaz, Sara; Schwartz, Thomas; Sheng, Hongjie; Sørum, Henning; Stedtfeld, Robert D.; Tiedje, James M.; Giustina, Saulo Varela Della; Walsh, Fiona; Vaz-Moreira, Ivone; Virta, Marko; Manaia, Célia M.Integrated antibiotic resistance (AR) surveillance is one of the objectives of the World Health Organization global action plan on antimicrobial resistance. Urban wastewater treatment plants (UWTPs) are among the most important receptors and sources of environmental AR. On the basis of the consistent observation of an increasing north-to-south clinical AR prevalence in Europe, this study compared the influent and final effluent of 12 UWTPs located in seven countries (Portugal, Spain, Ireland, Cyprus, Germany, Finland, and Norway). Using highly parallel quantitative polymerase chain reaction, we analyzed 229 resistance genes and 25 mobile genetic elements. This first trans-Europe surveillance showed that UWTP AR profiles mirror the AR gradient observed in clinics. Antibiotic use, environmental temperature, and UWTP size were important factors related with resistance persistence and spread in the environment. These results highlight the need to implement regular surveillance and control measures, which may need to be appropriate for the geographic regions.
- Antibiotic-resistant E.Coli in an UV-treated effluent: Troubled waters ahead?Publication . Tavares, Rafael; Silva, Isabel; Figueiredo, Sofia; Manaia, Célia M.; Tacão, Marta; Henriques, Isabel
- Assessment of rhizospheric culturable bacteria of Phragmites australis and Juncus effusus from polluted sitesPublication . Pereira, Sofia I. A.; Pires, Carlos; Henriques, Isabel; Correia, António; Magan, Naresh; Castro, Paula M. L.This study aimed at the isolation and characterization of metal(loid)-tolerant bacteria from the rhizosphere of Phragmites australis and Juncus effusus plants growing in two long-term contaminated sites in Northern Portugal. Site 1 had higher contamination than Site 3. Bacteria were isolated using metal(loid)-supplemented (Cd, Zn, and As) media. Isolates were grouped by random amplified polymorphic DNA and identified by 16S rRNA gene sequencing. Strains were also examined for their metal(loid) tolerance. The counts of metal(loid)-tolerant bacteria were higher in Site 1 and ranged between log 7.17 CFU g(-1) soil in As-containing medium and log 7.57 CFU g(-1) soil in Zn-containing medium, while counts at Site 3 varied between log 5.33 CFU g(-1) soil in Cd-containing medium and log 6.97 CFUg(-1) soil in As-containing medium. The composition of bacterial populations varied between locations. In Site 1, the classes Actinobacteria (36%) and Bacilli (24%) were well represented, while in Site 3 strains were mainly affiliated to classes Actinobacteria (35%), 'y-Proteobacteria (35%), and 13-Proteobacteria (12%). The order of metal(loid) toxicity for the isolated strains was Cd > As > Zn. Overall, 10 strains grew at 500 mg Cd L-1, 1000 mg Zn L-1, and 500 mg As L-1, being considered the most metal(loid)-tolerant bacteria. These strains belonged to genera Cupriavidus, Burkholderia, Novosphingobium, Sphingo bacterium, Castellaniella, Mesorhizobium, Chryseobacterium, and Rhodococcus and were mainly retrieved from Site 1. The multiple metal(loid)-tolerant strains isolated in this study have potential to be used in bioremediation/phytoremediation.
- Bacterial community and antibiotic resistance dynamics in a full-scale wastewater treatment plant with UV disinfectionPublication . Narciso-Da-Rocha, Carlos; Rocha, Jaqueline; Vaz-Moreira, Ivone; Lira, Felipe; Tamames, Javier; Henriques, Isabel; Martinez, José Luis; Manaia, Célia M.
- Bacterial community dynamics within an aerobic granular sludge reactor treating wastewater loaded with pharmaceuticalsPublication . Amorim, Catarina L.; Alves, Marta; Castro, Paula M.L.; Henriques, IsabelPharmaceuticals are micropollutants often present in wastewater treatment systems. In this study, the potential impact of such micropollutants on the bacterial population within aerobic granular sludge (AGS) bioreactor was investigated. The AGS bacterial community structure and composition were accessed combining DGGE fingerprinting and barcoded pyrosequencing analysis. Both revealed the existence of a dynamic bacterial community, independently of the pharmaceuticals presence. The AGS microbiome at both phylum and class levels varied over time and, after stopping pharmaceuticals feeding, the bacterial community did not return to its initial composition. Nevertheless, most of the assigned OTUs were present throughout the different operational phases. This core microbiome, represented by over 72% of the total sequences in each phase, probably played an important role in biological removal processes, avoiding their failure during the disturbance period. Quantitative-PCR revealed that pharmaceuticals load led to gradual changes on the abundance of ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB) and polyphosphate-accumulating organisms (PAO) but their persistence during that phase demonstrated the resilience of such bacterial groups. AGS microbiome changed over time but a core community was maintained, probably ensuring the accomplishment of the main biological removal processes.
- Bacterial lineages putatively associated with the dissemination of antibiotic resistance genes in a full-scale urban wastewater treatment plantPublication . Narciso-da-Rocha, Carlos; Rocha, Jaqueline; Vaz-Moreira, Ivone; Lira, Felipe; Tamames, Javier; Henriques, Isabel; Martinez, Jose Luis; Manaia, Célia M.Urban wastewater treatment plants (UWTPs) are reservoirs of antibiotic resistance. Wastewater treatment changes the bacterial community and inevitably impacts the fate of antibiotic resistant bacteria and antibiotic resistance genes (ARGs). Some bacterial groups are major carriers of ARGs and hence, their elimination during wastewater treatment may contribute to increasing resistance removal efficiency. This study, conducted at a full-scale UWTP, evaluated variations in the bacterial community and ARGs loads and explored possible associations among them. With that aim, the bacterial community composition (16S rRNA gene Illumina sequencing) and ARGs abundance (real-time PCR) were characterized in samples of raw wastewater (RWW), secondary effluent (sTWW), after UV disinfection (tTWW), and after a period of 3 days storage to monitoring possible bacterial regrowth (tTWW-RE). Culturable enterobacteria were also enumerated. Secondary treatment was associated with the most dramatic bacterial community variations and coincided with reductions of ~2 log-units in the ARGs abundance. In contrast, no significant changes in the bacterial community composition and ARGs abundance were observed after UV disinfection of sTWW. Nevertheless, after UV treatment, viability losses were indicated ~2 log-units reductions of culturable enterobacteria. The analysed ARGs (qnrS, blaCTX-M, blaOXA-A, blaTEM, blaSHV, sul1, sul2, and intI1) were strongly correlated with taxa more abundant in RWW than in the other types of water, and which associated with humans and animals, such as members of the families Campylobacteraceae, Comamonadaceae, Aeromonadaceae, Moraxellaceae and Bacteroidaceae. Further knowledge of the dynamics of the bacterial community during wastewater treatment and its relationship with ARGs variations may contribute with information useful for wastewater treatment optimization, aiming at a more effective resistance control.
- Bioremediation of coastal aquaculture effluents spiked with florfenicol using microalgae-based granular sludge – a promising solution for recirculating aquaculture systemsPublication . Oliveira, Ana S.; Alves, Marta; Leitão, Frederico; Tacão, Marta; Henriques, Isabel; Castro, Paula M. L.; Amorim, Catarina L.Aquaculture is a crucial industry in the agri-food sector, but it is linked to serious environmental problems. There is a need for efficient treatment systems that allow water recirculation to mitigate pollution and water scarcity. This work aimed to evaluate the self-granulation process of a microalgae-based consortium and its capacity to bioremediate coastal aquaculture streams that sporadically contain the antibiotic florfenicol (FF). A photo-sequencing batch reactor was inoculated with an autochthonous phototrophic microbial consortium and was fed with wastewater mimicking coastal aquaculture streams. A rapid granulation process occurred within ca. 21 days, accompanied by a substantially increase of extracellular polymeric substances in the biomass. The developed microalgae-based granules exhibited high and stable organic carbon removal (83-100%). Sporadically wastewater contained FF which was partially removed (ca. 5.5-11.4%) from the effluent. In periods of FF load, the ammonium removal slightly decreased (from 100 to ca. 70%), recovering 2 days after FF feeding ceased. A high-chemical quality effluent was obtained, complying with ammonium, nitrite, and nitrate concentrations for water recirculation within a coastal aquaculture farm, even during FF feeding periods. Members belonging to the Chloroidium genus were predominant in the reactor inoculum (ca. 99%) but were replaced from day-22 onwards by an unidentified microalga from the phylum Chlorophyta (>61%). A bacterial community proliferated in the granules after reactor inoculation, whose composition varied in response to feeding conditions. Bacteria from the Muricauda and Filomicrobium genera, Rhizobiaceae, Balneolaceae, and Parvularculaceae families, thrived upon FF feeding. This study demonstrates the robustness of microalgae-based granular systems for aquaculture effluent bioremediation, even during periods of FF loading, highlighting their potential as a feasible and compact solution in recirculation aquaculture systems.
- Characterization of multi-drug resistant Escherichia coli in the UV-treated outflow of an urban wastewater treatment plantPublication . Tavares, Rafael D. S.; Tacão, Marta; Figueiredo, Sofia; Duarte, Ana S.; Manaia, Célia; Henriques, Isabel
- Common and distinctive genomic features of Klebsiella pneumoniae thriving in the natural environment or in clinical settingsPublication . Rocha, Jaqueline; Henriques, Isabel; Gomila, Margarita; Manaia, Célia M.The Klebsiella pneumoniae complex is comprised of ubiquitous bacteria that can be found in soils, plants or water, and as humans’ opportunistic pathogens. This study aimed at inferring common and distinctive features in clinical and environmental K. pneumoniae. Whole genome sequences of members of the K. pneumoniae complex (including K. variicola, n = 6; and K. quasipneumoniae, n = 7), of clinical (n = 78) and environmental (n = 61) origin from 21 countries were accessed from the GenBank. These genomes were compared based on phylogeny, pangenome and selected clinically relevant traits. Phylogenetic analysis based on 2704 genes of the core genome showed close relatedness between clinical and environmental strains, in agreement with the multi-locus sequence typing. Eight out of the 62 sequence types (STs) identified, included both clinical and environmental genomes (ST11, ST14, ST15, ST37, ST45, ST147, ST348, ST437). Pangenome-wide association studies did not evidence significant differences between clinical and environmental genomes. However, the genomes of clinical isolates presented significantly more exclusive genes related to antibiotic resistance/plasmids, while the environmental isolates yielded significantly higher allelic diversity of genes related with functions such as efflux or oxidative stress. The study suggests that K. pneumoniae can circulate among the natural environment and clinical settings, probably under distinct adaptation pressures.
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