Olga Nunes

University of Porto | UP · Faculty of Engineering

Carbapenem-resistant Klebsiella pneumoniae represents a healthcare threat, already disseminated in the environment. This study aimed to compare the behaviour of a clinical and an environmental K. pneumoniae strain (multilocus sequence type ST147) harbouring the gene blaKPC-3 in water. The abundance of the genes phoE (specific for K. pneumoniae) and...

Graphitic carbon nitride (GCN) is an optical semiconductor with excellent photoactivity under visible light irradiation. It has been widely applied for organic micropollutant removal from contaminated water, and less investigated for microorganisms' inactivation. The photocatalytic degradation mechanism using GCN is attributed to a series of reacti...

Pseu.do.gul.ben.ki.a'ni.a Gr. neut. adj. pseudes , false; N.L. fem. n. Gulbenkiania , a bacterial generic name; N.L. fem. n. Pseudogulbenkiania , false Gulbenkiania . Proteobacteria / Betaproteobacteria / Neisseriales / Chromobacteriaceae / Pseudogulbenkiania Rods , non‐spore‐forming, Gram‐stain‐negative. Motile by a polar flagellum. Aerobic with c...

This work demonstrates the suitability of employing carbon-based catalytic membranes for persulfate activation and water disinfection in continuous flow mode of operation for the first time. Poly(vinylidene fluoride) (PVDF) membranes with and without nitrogen-doped reduced graphene oxide (rGO-M) were prepared and tested. The cumulative effect of ea...

The low-efficiency rate of urban wastewater (UWW) treatment generates tons of discharged water with a high concentration of pollutants, pathogens and antibiotic-resistance genes (ARGs). Microalgal systems may be a green alternative to be implemented as a UWW polishing treatment. This study assessed the ability of Chlorella vulgaris and UWW autochth...

Water is the most valuable resource on the planet. However, massive anthropogenic activities generate threatening levels of biological, organic, and inorganic pollutants that are not efficiently removed in conventional wastewater treatment systems. High levels of conventional pollutants (carbon, nitrogen, and phosphorus), emerging chemical contamin...

The presence of heavy metals and/or harmful bacteria in drinking water represents significant risks to human health. This study aimed to develop a low-cost water treatment technology using synthesized nanocomposites with metal nanoparticles (MNPs) supported on activated carbon (AC) for bacteria and heavy metal removal. In addition, the performance...

In this study, a combination of coagulation/flocculation and Fenton processes was studied as tertiary treatment in order to generate treated water susceptible to reuse. The combination of both processes has never been applied in disinfection of real urban wastewater. The best removals of turbidity and enterobacteria were achieved when applying a co...

Demineralized and disinfected waters may have very low microbial loads, requiring that large volumes of water are filtered to recover enough biomass for further analysis. Extended filtration periods, often interrupted by clogging, are a major limiting factor to concentrate samples’ microbiota for further examination, besides hindering the work pace...

Antibiotic resistant bacteria and antibiotic resistance genes are important environmental contaminants. Nonetheless, what drives the evolution, spread and transmission of antibiotic resistance dissemination is still poorly understood. The abundance of antibiotic resistant bacteria and antibiotic resistance genes is often elevated in human impacted...

Gulosibacter molinativorax ON4T is the only known organism to produce molinate hydrolase (MolA), which catalyses the breakdown of the thiocarbamate herbicide into azepane-1-carboxylic acid (ACA) and ethanethiol. A combined genomic and transcriptomic strategy was used to fully characterize the strain ON4T genome, particularly the molA genetic enviro...

Gulbenkiania (Gul.ben.ki.a'ni.a. N.L. fem. n. Gulbenkiania in honor of Calouste Gulbenkian (1869–1955), a protector of the arts and sciences in Portugal and founder of the Fundação Calouste Gulbenkian). Proteobacteria / Betaproteobacteria / Neisseriales / Chromobacteriaceae / Gulbenkiania Rods , non‐spore‐forming, and Gram‐staining‐negative. Motile...

Paracandidimonas (Pa.ra.can.di.di.mo'nas. Gr. prep. para like; N.L. fem. n. Candidimonas bacterial genus name; N.L. fem. n. Paracandidimonas a bacterium like Candidimonas ). Proteobacteria / Betaproteobacteria / Burkholderiales / Alcaligenaceae / Paracandidimonas Rods , non‐spore‐forming, and Gram‐staining‐negative. Aerobic or facultatively aerobic...

Pusillimonas (Pu.sil.li.mo'nas. L. masc. adj. pusillus very small/minute; Gr. fem. n. monas unit/monad; N.L. fem. n. Pusillimonas very small monad/unicell, referring to the small size of cells and colonies of the type species). Proteobacteria / Betaproteobacteria / Burkholderiales / Alcaligenaceae / Pusillimonas Rods , Gram‐stain‐negative, and nonm...

Parapusillimonas (Pa.ra.pu.sil.li.mo'nas. Gr. prep. para like; N.L. fem. n. Pusillimonas bacterial genus name; N.L. fem. n. Parapusillimonas a bacterium like Pusillimonas ). Proteobacteria / Betaproteobacteria / Burkholderiales / Alcaligenaceae / Parapusillimonas Gram‐staining‐negative motile short rods , with three flagella . Facultatively anaerob...

To address the increasing contamination of aquatic environments and incidence of waterborne diseases, advanced oxidation processes with activated persulfate have emerged as tools to inactivate wastewater microorganisms and contaminants. In this work, the disinfection of a secondary effluent from a wastewater treatment plant by iron-based persulfate...

Improving the chemical and biological quality of treated wastewater is particularly important in world regions under water stress. In these regions, reutilization of wastewater is seen as an alternative to reduce water demand, particularly for agriculture irrigation. In a reuse scenario, the treated wastewater must have enough quality to avoid chem...

Today, various methods such as bioleaching are increasingly used to remove toxic and reuse useful metals from low-grade ores and tailings. Bioleaching is an ecologically based technique carried by iron or sulfur-oxidizing bacteria, which convert insoluble metal sulfide to soluble metal sulfate. The purpose of this study was to test and compare two...

Pa.lu.di.bac.te'ri.um. L. fem. n. palus -udis a marsh; L. neut. n. bacterium a rod; N.L. neut. n. Paludibacterium a rod isolated from peat. Proteobacteria / Betaproteobacteria / Neisseriales / Chromobacteriaceae / Paludibacterium Curved rods, non-spore-forming, and Gram-stain negative. Motile by means of a single polar flagellum. Facultative anaero...

Disinfection is a crucial step during the water treatment process due to the significant risks of water contamination with human and animal excreta. The development of innovative disinfection technologies that can be applied at water point of use, avoiding contamination problems in water distribution systems and reservoirs, are needed. Thus, the pr...

Ozonation is among the currently used technologies to remove chemical and biological contaminants from secondary treated urban wastewater (UWW). Despite its effectiveness on the abatement of organic micropollutants (OMPs) and disinfection, previous studies have shown that regrow of bacteria may occur upon storage of the ozonated UWW. This reactivat...

Ozone-based water treatments were investigated to simultaneously remove organic micropollutants (OMPs) and bacteria from surface water samples collected in a river reservoir supplying a drinking water treatment plant. Among the 21 environmentally relevant OMPs selected, 15 were detected at low (< 20) ng L⁻¹ level. Surface water samples were then sp...

The exposure of soil to metals and to antibiotic resistant bacteria may lead to the progressive deterioration of soil quality. The persistence of antibiotic resistant bacteria or antibiotic resistance genes in soil can be influenced by the microbial community or by soil amendments with metal salts. This work assessed the effect of soil amendment wi...

Carbapenem-resistant Klebsiella pneumoniae are a major global threat in healthcare facilities. The propagation of carbapenem resistance determinants can occur through vertical transmission, with genetic elements being transmitted by the host bacterium, or by horizontal transmission, with the same genetic elements being transferred among distinct ba...

Schle.gel.el'la. L. fem. dim. ending ‐ella; N.L. fem. n. Schlegelella named in honor of H. G. Schlegel, a pioneer in PHA research. Proteobacteria / Betaproteobacteria / Burkholderiales / Comamonadaceae / Schlegelella Short rods 0.8–2.8 μm long and 0.4–0.6 μm wide. Motile. Gram‐negative. Nonsporulating. Aerobe. Moderately thermophilic or mesophilic,...

Can.di.di.mo'nas. L. masc. adj. candidus white; L. fem. n. monas a unit, monad; N.L. fem. n. Candidimonas a unit (rod) that produces white colonies. Proteobacteria / Betaproteobacteria / Burkholderiales / Alcaligenaceae / Candidimonas Rods, non‐spore‐forming, Gram‐stain‐negative. Nonmotile or motile by polar flagella. Aerobic or facultatively aerob...

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...

Sulfonamides are the oldest class of synthetic antibiotics still in use in clinical and veterinary settings. The intensive utilization of sulfonamides has been leading to the widespread contamination of the environment with these xenobiotic compounds. Consequently, in addition to pathogens and commensals, also bacteria inhabiting a wide diversity o...

Water is one of the main sources of human pathogenic microorganisms in developing countries. Therefore, new low-cost water treatment technologies are required to prevent public health problems. The main goal of this work was to develop a water purification technology using magnetic nanoparticles, to be applied in a water outlet point where the cont...

Tertiary treatments capable of removing chemical and biological contaminants of emerging concern have been successfully developed and implemented at full scale, opening the possibility of using wastewater treatment plants as recycling units, capable of producing wastewater that can be reused in various activities, such as agriculture irrigation; Ho...

The World Health Organization Global Action Plan recommends integrated surveillance programs as crucial strategies for monitoring antibiotic resistance. Although several national surveillance programs are in place for clinical and veterinary settings, no such schemes exist for monitoring antibiotic-resistant bacteria in the environment. In this tra...

The present work is the first report characterising bacterial communities recovered from sulphide ore from a Portuguese active mine (Neves-Corvo) and collecting samples from three independent processing stages (feed/tailings/paste), at three sampling periods over 15 months. The recovered bacterial communities demonstrated low richness and heterogen...

Relationships between collective scientific knowledge and country's economic prosperity and competitiveness have been described. Hence, interactions between industry and academic institutions is seen as a way to valorize this knowledge at social and economic levels. The ability to translate scientific knowledge in social and economic benefits is no...

Caenimicrobium [Cae.ni.mi.cro'bi.um, L. neut. n. caenum mud, referring to the isolation of the type strain from activated sludge; N.L. neut. n. microbium microbe (from Gr. adj. mikros small and Gr. n. bios life); N.L. neut. n. Caenimicrobium mud (‐inhabiting) microbe]. Proteobacteria / Betaproteobacteria / Burkholderiales / Alcaligenaceae / Caenimi...

We have recently argued that, because microbes have pervasive – often vital – influences on our lives, and that therefore their roles must be taken into account in many of the decisions we face, society must become microbiology‐literate, through the introduction of relevant microbiology topics in school curricula (Timmis et al. 2019. Environ Microb...

Alicycliphilus (A.li.cy.cli'phi.lus. Gr. neut. n. aleiphar annointing oil; Gr. masc. n. kyklos circle or ring; Gr. masc. n. philos friend; N.L. masc. n. Alicyciphilus alicyclic compound liking, referring to the substrates used for the isolation of this organism). Proteobacteria / Betaproteobacteria / Burkholderiales / Comamonadaceae / Alicycliphilu...

Melaminivora [Me.la.mi.ni.vo'ra. N.L. neut. n. melaminum melamine; L. v. voro to eat, to devour; N.L. fem. n. Melaminivora melamine eating]. Proteobacteria / Betaproteobacteria / Burkholderiales / Comamonadaceae / Melaminivora Rods 2.0–3.5‐μm long and 0.5–0.9‐μm wide. Motile by a single unipolar flagellum. Gram‐negative . Nonsporulating. Aerobe . N...

Diaphorobacter [Di.a.pho.ro.bac'ter. Gr. masc. adj. diaphoros different, profitable; N.L. masc. n. bacter rod; N.L. masc. n. Diaphorobacter distinguished and profitable rod, referring to usefulness in nitrogen removal]. Proteobacteria / Betaproteobacteria / Burkholderiales / Comamonadaceae / Diaphorobacter Rods , non‐spore‐forming, Gram‐stain‐negat...

Te.pi.di'phi.lus. L. masc. adj. tepidus lukewarm; Gr. masc. adj. philos friendly to; N.L. masc. n. Tepidiphilus liker of lukewarm conditions. Proteobacteria / Hydrogenophilia / Hydrogenophilales / Hydrogenophilaceae / Tepidiphilus Rods with poly‐beta‐hydroxybutyrate granules, non‐spore forming, Gram‐negative with a single polar flagellum . Aerobic,...

Hy.dro.mo'nas. Gr. neut. n. hydor water; L. fem. n. monas a unit, monad; N.L. fem. n. Hydromonas a unit (monad) from water. Proteobacteria / Betaproteobacteria / Burkholderiales / Burkholderiaceae / Hydromonas Rods with electron‐dense intracellular inclusions, non‐spore‐forming, Gram‐negative. Aerobic, mesophilic, with the ability to grow between 1...

O.ry.zi.so.li.bac'ter. L. fem. n. oryza rice; L. neut. n. solum soil; N.L. masc. n. bacter rod; N.L. masc. n. Oryzisolibacter rod from rice crop bulk soil. Proteobacteria / Betaproteobacteria / Burkholderiales / Comamonadaceae / Oryzisolibacter Rods 1.9 ± 0.35‐μm long and 0.6 ± 0.04‐μm wide. Motile . Gram‐negative . Nonsporulating. Facultative aero...

Hy.dro.ge.ni'phi.lus. Gr. neut. n. hydor water; Gr. v. genein to produce; N.L. neut. n. hydrogenum hydrogen (that which produces water); Gr. masc. adj. philos loving, friendly to; N.L. masc. n. Hydrogenophilus hydrogen lover. Proteobacteria / Betaproteobacteria / Hydrogenophilales / Hydrogenophilaceae / Hydrogenophilus Straight rods , 0 . 4–0 . 8 ×...

Background: Microbial communities recurrently establish metabolic associations resulting in increased fitness and ability to perform complex tasks, such as xenobiotic degradation. In a previous study, we have described a sulfonamide-degrading consortium consisting of a novel low-abundant actinobacterium, named strain GP, and Achromobacter denitrif...

Antibiotic resistance is a global problem that must be managed under the One Health perspective. Retrospectively, it is assumed that microbial populations able to cope with compounds with antimicrobial activity and susceptible bacteria lived in equilibrium for a thousand years. This situation would change in the middle 1940s of the twentieth centur...

The presence of antibiotic resistant-bacteria (ARB) and antibiotic resistance genes (ARG) in treated effluents of urban wastewater treatment plants (WWTP) may represent a threat to the environment and public health. Therefore, cost-effective technologies contributing to minimize loads of these contaminants in the final effluents of WWTP are require...

History shows that the discovery of, and the resistance to, antibiotics go hand in hand. While knowledge of resistance mechanisms, their impact and distribution is vast, over the years, the topic of antibiotic degradation has often been overlooked and regarded as being discrete from the research on resistance. As a result, understanding of the degr...

Antibiotic residues are widespread in the environment and their presence is known to contribute to the propagation of antibiotic resistance. Nevertheless, knowledge on processes involved in their degradation is scattered. This second part of a two part review aims at compiling knowledge on the (bio-) degradation of antibiotics, focusing on β-lactam...

Functional cotton fabrics consisting of neat polymeric carbon nitride (CN) combined with graphene oxide (GO) were prepared by a simple impregnation route. The CN-based coated fabrics were characterized by several techniques. The self-cleaning efficiency of these hybrid fabrics was assessed in the photocatalytic degradation of caffeine and rhodamine...

Conclusions • P. aeruginosa and hosted bla VIM and intI1 genes persist in soil slurries irrespective of the metal salts presence. • After 14 days of incubation, in presence of the metals, the P. aeruginosa housekeeping gene ecf decreased more than the ARG bla VIM • Further assays are ongoing to define the impact of the soil contamination with metal...

This work evaluated the removal of a mixture of eight antibiotics (i.e. ampicillin (AMP), azithromycin (AZM), erythromycin (ERY), clarithromycin (CLA), ofloxacin (OFL), sulfamethoxazole (SMX), trimethoprim (TMP) and tetracycline (TC)) from urban wastewater, by ozonation operated in continuous mode at different hydraulic retention times (HRTs) (i.e....

Secondary urban wastewater samples were spiked with azithromycin (AZT), trimethoprim (TMP), ofloxacin (OFL) and sulfamethoxazole (SMX) at 100 µg L ⁻¹ to investigate the efficiency of a TiO 2 -photocatalytic treatment using UVA-LEDs. Different operating parameters were studied, such as the irradiation conditions, catalyst load and the use of methano...

In the last decade, biological degradation and mineralization of antibiotics have been increasingly reported feats of environmental bacteria. The most extensively described example is that of sulfonamides that can be degraded by several members of Actinobacteria and Proteobacteria. Previously, we reported sulfamethoxazole (SMX) degradation and part...

Bacteria harboring conjugative plasmids have the potential for spreading antibiotic resistance through horizontal gene transfer. It is described that the selection and dissemination of antibiotic resistance is enhanced by stressors, like metals or antibiotics, which can occur as environmental contaminants. This study aimed at unveiling the composit...

This study determined the limit of quantification (LOQ) values that can be achieved using current methodologies to quantify antibiotic resistance genes (ARGs) in soils. The LOQ values found can be considered extremely high to perform an accurate assessment of the impacts of ARGs discharges in soils. Our key message is that ARGs accumulation will...

Antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) can be discharged in soil through irrigation or other agricultural practices, from sources that may contain other contaminants such as metals. These contaminants may drive changes in the soil microbial community and generate selective pressures. In this study, we assessed th...

The determination of values of abundance of antibiotic resistance genes (ARGs) per mass of soil is extremely useful to assess the potential impacts of relevant sources of antibiotic resistance, such as irrigation with treated wastewater or manure application. Culture-independent methods and, in particular, quantitative PCR (qPCR), have been regarde...

Achromobacter denitrificans strain PR1, previously found to harbor specific degradation pathways with high sulfamethoxazole (SMX) degradation rates, was bioaugmented into laboratory-scale membrane bioreactors (MBRs) operated under aerobic conditions to treat SMXcontaining real domestic wastewater. Different hydraulic retention times (HRTs), which i...

The effect of different membranes, membrane modules, feed temperatures, flow rates and solute concentrations on the permeate flux and salt rejection in direct contact membrane distillation (DCMD) was first studied with synthetic seawater and compared to distilled water. After optimizing these operating conditions, DCMD was tested with real feed sam...

Although sulfonamide residues are frequently reported as freshwaters contaminants, information on the ability of native bacteria to modify these synthetic antibiotics is scarce. Our purpose was to investigate the potential of bacteria from different aquatic environments to cleave or transform sulfamethoxazole (SMX) and infer on their ability to red...

The role of water in the TiO2-based photocatalytic phenomenon is not yet fully understood. The photocatalysis of methylene blue dissolved in propylene carbonate and different concentrations of water was studied. It was observed that the photocatalytic activity of TiO2 (P25 from Evonik) peaks when propylene carbonate solvent is used with minute amou...

Solar-driven advanced oxidation processes were studied in a pilot-scale photoreactor, as tertiary treatments of effluents from an urban wastewater treatment plant. Solar-H2O2, heterogeneous photocatalysis (with and/or without the addition of H2O2 and employing three different photocatalysts) and the photo-Fenton process were investigated. Chemical...

Strain EPL6T, a Gram-negative, motile, short rod was isolated from a propanil and 3,4-dichloroaniline enrichment culture produced from rice paddy soil. Based on the analyses of the 16S rRNA gene sequence, strain EPL6T was observed to be a member of the family Comamonadaceae, sharing the highest pairwise identity with type strains of the species Ali...

Achromobacter denitrificans strain PR1 was isolated from an enrichment culture able to use sulfamethoxazole as an energy source. Here, we describe the complete genome of this strain sequenced by Illumina MiSeq and Oxford Nanopore MinION.

Sulfonamide antibiotics compete with p-aminobenzoic acid for the active sites of dihydropteroate synthase (DHPS), blocking the synthesis of folic acid in bacteria. They are micropollutants and the removal efficiencies in conventional wasterwater treatment plants (WWTP) are variable. They are often found in wastewater, surface water and groundwater....

Pure cultures have been found to degrade pharmaceutical compounds. However, these cultures are rarely characterized kinetically at environmentally relevant concentrations. This study investigated the kinetics of sulfamethoxazole (SMX) degradation by Achromobacter denitrificans strain PR1 at a wide range of concentrations, from ng/L to mg/L, to asse...

Optical mapping (OM) has been used in microbiology for the past 20 years, initially as a technique to facilitate DNA sequence-based studies; however, with decreases in DNA sequencing costs and increases in sequence output from automated sequencing platforms, OM has grown into an important auxiliary tool for genome assembly and comparison. Currently...

“Masseiras” is an ancient Portuguese agriculture system, where soil was developed from sand dunes enriched with seaweeds over more than a century. Due to the importance for the local economy, this system evolved for greenhouse structures. In this study we compared the bacterial community composition and structure of “Masseiras” soil, aiming at asse...

Molinate is a thiocarbamate herbicide used in rice crop protection. As other pesticides, molinate is a recognized environmental pollutant and bio-accumulated by some wildlife forms. Gulosibacter molinativorax ON4(T) is able to hydrolyse molinate into metabolites which are further degraded by other un-related bacteria. Hence, it can be used in molin...

Drinking water comprises a complex microbiota, in part shaped by the disinfection and distribution systems. Gram-negative bacteria, mainly members of the phylum Proteobacteria, represent the most frequent bacteria in drinking water, and their ubiquity and physiological versatility raises questions about possible implications in human health. The fi...

TiO2 semiconductor is being investigated and used for different applications such as energy production, photoinactivation, photoabatement, self-cleaning and water desalination. TiO2 has, however, a large band gap, ca. 3.2 eV, which limits its absorption to UV light range that accounts only for ca. 5% of the solar spectrum energy. Therefore, strateg...

Bottled water” refers to natural or treated water that reaches the consumer as a packaged product, normally a glass or plastic container. Mineral or spring waters that do not suffer any treatment capable of altering their natural microbiota are appreciated by consumers and constitute interesting microbial habitats. These types of water have a rich...

The main purpose of this work was to assess the (i) short-term effect of the main nitrification and denitrification variables on the nitrogen’s biological removal via nitrite from highstrength leachates, and (ii) the effect of the presence/absence of nitrites/nitrates in a downstream photo-oxidation process. The biological reaction rates were evalu...

Previous studies demonstrated the capability of mixed culture DC1 to mineralize the thiocarbamate herbicide molinate through the activity of molinate hydrolase (MolA). Because liquid suspensions are not compatible with long-term storage and are not easy to handle when bioremediation strategies are envisaged, in this study spray drying was evaluated...

Implant-associated infections are caused by surface-adhering microorganisms persisting as biofilms, resistant to host defence and antimicrobial agents. Given the limited efficacy of traditional antibiotics, novel strategies may rely on the prevention of such infections through the design of new biomaterials. In the present work, two antimicrobial a...

Although alkaline hydrolysis emerges as an alternative process to treat healthcare waste (HCW), information about its emissions is scarce, namely as regards effluents production. This work aims to characterize the effluents from alkaline hydrolysis tests with samples of components usually present in HCW, under a temperature of 110°C and with 1 M Na...

Disinfection processes aim at reducing the number of viable cells through the generation of damages in different cellular structures and molecules. Since disinfection involves unspecific mechanisms, some microbial populations may be selected due to resilience to treatment and/or to high post-treatment fitness. In this study, the bacterial community...

To evaluate the anti-adhesive properties of chlorhexidine digluconate (CHX)-loaded nanohydroxyapatite materials against single- and dual-species biofilm of S. aureus and E. coli. Methods: S. aureus and E. coli (alone and in combination) were inoculated into cultures containing the biomaterials. The resulting biofilms were quantified by the enumerat...

Previously, two municipal solid waste commercial composts (MSW1 and MSW2) were characterized. Although sharing the same type of raw material, most of their physicochemical, stability and maturity properties differed. The present study aimed to characterize them at a microbiological level, and to infer on possible relationships between the composts...