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- COST Action ES1403: New and Emerging challenges and opportunities in wastewater REUSe (NEREUS)Publication . Fatta-Kassinos, Despo; Manaia, C.; Berendonk, T. U.; Cytryn, E.; Bayona, J.; Chefetz, B.; Slobodnik, J.; Kreuzinger, N.; Rizzo, L.; Malato, S.; Lundy, L.; Ledin, A.
- Evolution of gentamicin and arsenite resistance acquisition in Ralstonia pickettii water isolatesPublication . Ferro, Pompeyo; Vaz-Moreira, Ivone; Manaia, Célia M.Ralstonia pickettii are ubiquitous in water environments. Members of this species are frequently, but not always, resistant to both gentamicin and arsenite. Gentamicin and arsenite co-resistance and the putative molecular mechanisms were investigated. A group of 37 R. pickettii strains isolated from drinking water and hospital wastewater were characterized for gentamicin and arsenite resistance phenotypes, the number and size of plasmids, and screened for genetic elements associated with arsenite tolerance, Integrative and Conjugative Elements (ICEs), among other. The genomes of three representative strains were compared. Most gentamicin resistant (GR) isolates (32/33) were resistant to arsenite, and harbored ICE- and ars operon-related genes. These genetic elements were not detected in any of the five arsenite susceptible strains, regardless of the GR (n = 1) or gentamicin susceptibility (GS) (n = 4) phenotype. The comparison of the genomes of two GR (one resistant and one susceptible to arsenite) and one GS strains suggested that these phenotypes correspond to three phylogroups, distinguished by presence of some genes only in GR isolates, in addition to point mutations in functional genes. The presence of ICEs and ars operon-related genes suggest that arsenite resistance might have been acquired by GR lineages.
- Acinetobacter rudis sp. nov., isolated from raw milk and raw wastewaterPublication . Vaz-Moreira, Ivone; Novo, Ana; Hantsis-Zacharov, Elionora; Lopes, Ana Rita; Gomila, Margarita; Nunes, Olga C.; Manaia, Célia M.; Halpern, MalkaTwo bacterial strains, G30T and A1PC16, isolated respectively from raw milk and raw wastewater, were characterized using a polyphasic approach. Chemotaxonomic characterization supported the inclusion of these strains in the genus Acinetobacter, with Q-8 and Q-9 as the major respiratory quinones, genomic DNA G+C contents within the range observed for this genus(38–47 mol%) and C16 : 0, C18 : 1v9c and C16 : 1v7c/iso-C15 : 0 2-OH as the predominant fatty acids. The observation of 16S rRNA gene sequence similarity lower than 97% with other Acinetobacter species with validly published names led to the hypothesis that these isolates could represent a novel species. This hypothesis was supported by comparative analysis of partial sequences of the genes rpoB and gyrB, which showed that strains G30T and A1PC16 did not cluster with any species with validly published names, forming a distinct lineage. DNA–DNA hybridizations confirmed that the two strains were members of the same species, which could be distinguished from their congeners by several phenotypic characteristics. On the basis of these arguments, it is proposed that strains G30T and A1PC16 represent a novel species, for which the name Acinetobacter rudis sp. nov. is proposed. The type strain is strain G30T (5LMG 26107T 5CCUG 57889T 5DSM 24031T 5CECT 7818T).
- Genotypic analysis of candida albicans isolates obtained from removable prosthesis wearersPublication . Costa, F.; Manaia, C. M.; Figueiral, M. H.; Pinto, E.Aims: To assess of the genotypic diversity of Candida albicans isolated from removable prosthesis wearers, with and without denture-related stomatitis (DRS). The occurrence of different genotypes in pathological and control cases was investigated. Methods and Results: One hundred and sixty-four isolates of C. albicans obtained from different oral cavity locations were compared by randomly amplified polymorphic DNA (RAPD). The coherence of this analysis was confirmed by genotyping a selected group of isolates with pulsed field gel electrophoresis (PFGE). Among the 164 isolates, 150 were grouped into seven groups on the basis of their RAPD patterns. Three of these groups (comprising 54 isolates) had significant (α < 0.10) predominance of clinical or control cases. For the other isolates, no significant differences were observed between control and DRS cases. Occasionally, more than one genotype was found in the same person. These findings were sustained by PFGE analysis. No relevant associations between the genotypic patterns and pathology level were found. Conclusions: This study evidenced that C. albicans with similar genotypes may be found in individuals with DRS and in control cases. Significance and Impact of the Study: This conclusion hints the involvement of other aetiological factors that alone or in association with C. albicans may trigger the emergence of DRS.
- The role of environmental stressors and genetic information on the antimicrobial tolerance of Ralstonia pickettiiPublication . Ferro, Pompeyo; Vaz-Moreira, Ivone; Tamames, Javier; Martínez, José L.; Manaia, C. M.
- blaTEM and vanA as indicator genes of antibiotic resistance contamination in a hospital–urban wastewater treatment plant systemPublication . Narciso-da-Rocha, Carlos; Varela, Ana R.; Schwartz, Thomas; Nunes, Olga C.; Manaia, Celia M.Four indicator genes were monitored by quantitative PCR in hospital effluent (HE) and in the raw and treated wastewater of the municipal wastewater treatment plant receiving the hospital discharge. The indicator genes were the class 1 integrase gene intI1, to assess the capacity of bacteria to be involved in horizontal gene transfer processes; blaTEM, one of the most widespread antibiotic resistance genes in the environment, associated with Enterobacteriaceae; vanA, an antibiotic resistance gene uncommon in the environment and frequent in clinical isolates; and marA, part of a locus related to the stress response in Enterobacteriaceae. Variation in the abundance of these genes was analysed as a function of the type of water, and possible correlations with cultivable bacteria, antimicrobial residue concentrations, and bacterial community composition and structure were analysed. HE was confirmed as an important source of blaTEM and vanA genes, and wastewater treatment showed a limited capacity to remove these resistance genes. The genes blaTEM and vanA presented the strongest correlations with culturable bacteria, antimicrobial residues and some bacterial populations, representing interesting candidates as indicator genes to monitor resistance in environmental samples. The intI1 gene was the most abundant in all samples, demonstrating that wastewater bacterial populations hold a high potential for gene acquisition
- Antibiotic resistance genes in the human-impacted environment: a one health perspectivePublication . Tiedje, James M.; Wang, Fang; Manaia, Célia M.; Virta, Marko; Sheng, Hongjie; Ma, Liping; Zhang, Tong; Topp, EdwardAntibiotic resistance and its environmental component are gaining more attention as part of combating the growing healthcare crisis. The One Health framework, promulgated by many global health agencies, recognizes that antimicrobial resistance is a truly inter-domain problem in which human health, animal agriculture, and the environment are the core and interrelated components. This prospectus presents the status and issues relevant to the environmental component of antibiotic resistance, namely, the needs for advancing surveillance methodology: the environmental reservoirs and sources of resistance, namely, urban wastewater treatment plants, aquaculture production systems, soil receiving manure and biosolid, and the atmosphere which includes longer range dispersal. Recently, much work has been done describing antibiotic resistance genes in various environments; now quantitative, mechanistic, and hypothesis-driven studies are needed to identify practices that reduce real risks and maintain the effectiveness of our current antibiotics as long as possible. Advanced deployable detection methods for antibiotic resistance in diverse environmental samples are needed in order to provide the surveillance information to identify risks and define barriers that can reduce risks. Also needed are practices that reduce antibiotic use and thereby reduce selection for resistance, as well as practices that limit the dispersal of or destroy antibiotic-resistant bacteria or their resistance genes that are feasible for these varied environmental domains.
- Antibiotic resistance, antimicrobial residues and bacterial community composition in urban wastewaterPublication . Novo, Ana; André, Sandra; Viana, Paula; Nunes, Olga C.; Manaia, Célia M.This study was based on the hypothesis that the occurrence of antimicrobial residues and antibiotic resistant bacteria in the sewage could be correlated with the structure and composition of the bacterial community and the antibiotic resistance loads of the final effluent. Raw and treated wastewater composite samples were collected from an urban treatment plant over 14 sampling dates. Samples were characterized for the i) occurrence of tetracyclines, penicillins, sulfonamides, quinolones, triclosan, arsenic, cadmium, lead, chromium and mercury; ii) antibiotic resistance percentages for tetracycline, sulfamethoxazole, ciprofloxacin and amoxicillin and iii) 16S rRNA gene-DGGE patterns. The data of corresponding samples, taking into account the hydraulic residence time, was analyzed using multivariate analysis. Variations on the bacterial community structure of the final effluent were significantly correlated with the occurrence of tetracyclines, penicillins, sulfonamides, quinolones and triclosan in the raw inflow. Members of the class Epsilonproteobacteria presented positive correlations with those antimicrobials, whereas negative correlations were observed with Beta and Gammaproteobacteria and Firmicutes. Antibiotic resistance percentages presented different trends of variation in heterotrophs/enterobacteria and in enterococci, varied over time and after wastewater treatment. Antibiotic resistance was positively correlated with the occurrence of tetracyclines residues and high temperature. A relationship between antibiotic residues, bacterial community structure and composition and antibiotic resistance is demonstrated. Further studies, involving more wastewater treatment plants may help to elucidate this complex relationship.
- A pilot study combining ultrafiltration with ozonation for the treatment of secondary urban wastewater: organic micropollutants, microbial load and biological effectsPublication . Graça, Cátia A. L.; Ribeirinho-Soares, Sara; Abreu-Silva, Joana; Ramos, Inês I.; Ribeiro, Ana R.; Castro-Silva, Sérgio M.; Segundo, Marcela A.; Manaia, Célia M.; Nunes, Olga C.; Silva, Adrián M. T.Ozonation followed by ultrafiltration (O3 + UF) was employed at pilot scale for the treatment of secondary urban wastewater, envisaging its safe reuse for crop irrigation. Chemical contaminants of emerging concern (CECs) and priority substances (PSs), microbial load, estrogenic activity, cell viability and cellular metabolic activity were measured before and immediately after O3 + UF treatment. The microbial load was also evaluated after one-week storage of the treated water to assess potential bacteria regrowth. Among the organic micropollutants detected, only citalopram and isoproturon were not removed below the limit of quantification. The treatment was also effective in the reduction in the bacterial loads considering current legislation in water quality for irrigation (i.e., in terms of enterobacteria and nematode eggs). However, after seven days of storage, total heterotrophs regrew to levels close to the initial, with the concomitant increase in the genes 16S rRNA and intI1. The assessment of biological effects revealed similar water quality before and after treatment, meaning that O3 + UF did not produce detectable toxic by-products. Thus, the findings of this study indicate that the wastewater treated with this technology comply with the water quality standards for irrigation, even when stored up to one week, although improvements must be made to minimise microbial overgrowth.
- Paenibacillus residui sp. nov., isolated from urban waste compostPublication . Vaz-Moreira, Ivone; Figueira, Vânia; Lopes, Ana Rita; Pukall, Rüdiger; Spröer, Cathrin; Schumann, Peter; Nunes, Olga C.; Manaia, Célia M.Two bacterial strains, MC-246T and MC-247, were isolated from municipal urban waste compost and characterized by a polyphasic approach. Both isolates were Gram-stain-variable, endosporeforming rods that were catalase-, oxidase- and b-galactosidase-positive, and able to grow at 25– 50 6C and pH 7.0–9.0, with optimum growth at 37 6C and pH 7. The predominant cellular fatty acids were anteiso-C15 : 0, iso-C15 : 0, iso-C16 : 0, anteiso-C17 : 0 and iso-C17 : 0; the major respiratory quinone was menaquinone MK-7; the cell wall peptidoglycan was of type A1c; and the DNA G+C content was 49 mol%. These characteristics, as well as data from 16S RNA gene sequence analysis, showed that these strains were affiliated with the genus Paenibacillus; the type strains of Paenibacillus ginsengarvi and Paenibacillus hodogayensis were among their closest neighbours (,94.2 % sequence similarity). Nevertheless, the hypothesis that strains MC246T and MC-247 could represent a novel species was supported by the low 16S rRNA gene sequence similarity values shared with other members of the genus Paenibacillus and by the observation of distinct biochemical and physiological traits. Strains MC-246T and MC-247 shared 99.6 % 16S rRNA gene sequence similarity and showed almost identical MALDI-TOF mass spectra, but could be distinguished at the phenotypic and genotypic level. However, DNA–DNA hybridization between strains MC-246T and MC-247 resulted in values above 70 % indicating that both organisms represent a single species, for which the name Paenibacillus residui sp. nov. is proposed; the type strain is MC-246T (5DSM 22072T 5CCUG 57263T).