A carregar...
Projeto de investigação
alterado para: Antimicrobial resistance, clonal diversity and biofilm formation of Staphylococcus aureus and other staphylococci: A One Health approach to a global threat Integrating multiple ‘omics’ analysis of methicillin-resistant Staphylococcus aureus MRSA biofilms: a One Health approach to a global threat
Financiador
Autores
Publicações
Exploring the Biofilm Formation Capacity in S. pseudintermedius and Coagulase-Negative Staphylococci Species
Publication . Silva, Vanessa; Correia, Elisete; Pereira, José Eduardo; González-Machado, Camino; Capita, Rosa; Alonso-Calleja, Carlos; Igrejas, Gilberto; Poeta, Patrícia; LAQV@REQUIMTE; DQ - Departamento de Química; MDPI - Multidisciplinary Digital Publishing Institute
The ability of biofilm formation seems to play an important role in the virulence of staphylococci. However, studies reporting biofilm formation of coagulase-negative staphylococci isolated from animals are still very scarce. Thus, we aimed to evaluate the biofilm-forming capacity of CoNS and S. pseudintermedius isolated from several animal species and to investigate the effect of conventional antimicrobials on biofilm reduction. A total of 35 S. pseudintermedius and 192 CoNS were included. Biofilm formation was accessed by the microtiter plate assay and the biofilms were stained by crystal violet. Association between biofilm formation and staphylococci species and antimicrobial resistance was also performed. Biofilm susceptibility testing was performed with tetracycline and amikacin at the minimum inhibitory concentration (MIC) and 10 × MIC. The metabolic activity of the biofilm cells after antimicrobial treatment was accessed by the XTT assay. All isolates formed biofilm, with S. urealyticus producing the most biofilm biomass and S. pseudintermedius producing the least biomass. There was a positive association between biofilm formation and multidrug resistance as well as resistance to individual antimicrobials. Neither tetracycline nor amikacin were able to eradicate the biofilm, not even at the highest concentration used. This study provides new insights into biofilm formation and the effects of antimicrobials on CoNS species.
Influence of Environmental Factors on Biofilm Formation of Staphylococci Isolated from Wastewater and Surface Water
Publication . Silva, Vanessa; Pereira, José Eduardo; Maltez, Luís; Poeta, Patrícia; Igrejas, Gilberto; LAQV@REQUIMTE; DQ - Departamento de Química; MDPI - Multidisciplinary Digital Publishing Institute
The presence of biofilms can negatively affect several different areas, such as the food industry, environment, and biomedical sectors. Conditions under which bacteria grow and develop, such as temperature, nutrients, and pH, among others, can largely influence biofilm production. Staphylococcus species survive in the natural environment due to their tolerance to a wide range of temperatures, dryness, dehydration, and low water activity. Therefore, we aimed to evaluate the influence of external environmental factors on the formation of biofilm of staphylococci isolated from hospital wastewater and surface waters. We investigated the biofilm formation of methicillin-resistant and -susceptible S. aureus (MRSA and MSSA) and coagulase-negative staphylococci (CoNS) under various temperatures, pH values, salt concentrations, glucose concentrations, and under anaerobic and aerobic conditions. CoNS had the ability to produce more biofilm biomass than MSSA and MRSA. All environmental factors studied influenced the biofilm formation of staphylococci isolates after 24 h of incubation. Higher biofilm formation was achieved at 4% of NaCl and 0.5% of glucose for MSSA and CoNS, and 1% of NaCl and 1.5% of glucose for MRSA isolates. Biofilm formation of isolates was greater at 25 °C and 37 °C than at 10 °C and 4 °C. pH values between 6 and 8 led to more robust biofilm formation than pH levels of 9 and 5. Although staphylococci are facultative anaerobes, biofilm formation was higher in the presence of oxygen. The results demonstrated that multiple environmental factors affect staphylococci biofilm formation. Different conditions affect differently the biofilm formation of MRSA, MSSA, and CoNS strains.
Molecular epidemiology of staphylococcus aureus lineages in wild animals in europe
Publication . Silva, Vanessa; Capelo, José L.; Igrejas, Gilberto; Poeta, Patrícia; LAQV@REQUIMTE; DQ - Departamento de Química; MDPI - Multidisciplinary Digital Publishing Institute
Staphylococcus aureus is an opportunist pathogen that is responsible for numerous types of infections. S. aureus is known for its ability to easily acquire antibiotic resistance determinants. Methicillin-resistant S. aureus (MRSA) is a leading cause of infections both in humans and animals and is usually associated with a multidrug-resistant profile. MRSA dissemination is increasing due to its capability of establishing new reservoirs and has been found in humans, animals and the environment. Despite the fact that the information on the incidence of MRSA in the environment and, in particular, in wild animals, is scarce, some studies have reported the presence of these strains among wildlife with no direct contact with antibiotics. This shows a possible transmission between species and, consequently, a public health concern. The aim of this review is to better understand the distribution, prevalence and molecular lineages of MRSA in European free-living animals.
Antimicrobial Resistance and Molecular Epidemiology of Staphylococcus aureus from Hunters and Hunting Dogs
Publication . Silva, Vanessa; Caniça, Manuela; Manageiro, Vera; Vieira‐Pinto, Madalena; Pereira, José Eduardo; Maltez, Luís; Poeta, Patrícia; Igrejas, Gilberto; LAQV@REQUIMTE; DQ - Departamento de Química; MDPI - Multidisciplinary Digital Publishing Institute
Several studies have showed that a dog‐to‐human transmission of Staphylococcus aureus occurs. Hunting dogs do not have as much contact with their owners as dogs that live in the same household as the owners; however, these dogs have contact with their owners during hunting activities as well as when hunting game; therefore, we aimed to isolate S. aureus from hunters and their hunting dogs to investigate a possible S. aureus transmission. Nose and mouth samples were collected from 30 hunters and their 78 hunting dogs for staphylococcal isolation. The species identification was performed using MALDI‐TOF. The antimicrobial susceptibility profiles were accessed using the Kirby–Bauer method and respective antimicrobial resistance genes were investigated by PCR. Multilocus sequence typing (MLST) and spa‐ and agr‐typing was performed in all S. aureus isolates. S. aureus were detected in 10 (30%) human samples and in 11 (15.4%) dog samples of which 11 and 5 were methicillin‐resistant S. aureus (MRSA). Other staphylococci were identified, particularly, S. pseudintermedius. Most S. aureus isolates were resistant to penicillin, erythromycin, and tetracycline. Evidence of a possible transmission of S. aureus between human and dogs was detected in three hunters and their dogs. S. aureus isolates were ascribed to 10 STs and 9 spa‐types. A moderate colonization of S. aureus in hunting dogs and their owners was detected in this study. A few dog‐to‐dog and dog‐to‐human possible transmissions were identified.
Multidrug-Resistant Methicillin-Resistant Coagulase-Negative Staphylococci in Healthy Poultry Slaughtered for Human Consumption
Publication . Silva, Vanessa; Caniça, Manuela; Ferreira, Eugénia; Vieira-Pinto, Madalena; Saraiva, Cândido; Pereira, José Eduardo; Capelo, José Luis; Igrejas, Gilberto; Poeta, Patrícia; LAQV@REQUIMTE; DQ - Departamento de Química; MDPI - Multidisciplinary Digital Publishing Institute
Coagulase-negative staphylococci are commensals that are known to be prevalent in most environments, and they are also an important reservoir of antimicrobial-resistant genes. Staphylococ-cal infections in animal husbandry are a high economic burden. Thus, we aimed to determine the prevalence and species diversity of methicillin-resistant coagulase-negative staphylococci (MRCoNS) in poultry slaughtered for human consumption and to study the antimicrobial resistance of the isolates. Swab samples were recovered from 220 commercial chickens, homebred chickens and quails. Species identification was performed using MALDI-TOF. Antimicrobial susceptibility testing was performed by the disc diffusion method against 14 antimicrobials. The presence of antimicrobial-resistant genes was investigated by polymerase chain reaction. Totals of 11 (19.6%), 13 (20.3%), and 51 (51%) MRCoNS were isolated from commercial chickens, homebred chickens and quails, respectively. S. lentus was isolated from all homebred chickens, whereas 11 S. lentus and 2 S. urealyticus were isolated from commercial chickens. As for quails, the most prevalent MRCoNS were S. urealyticus. Almost all isolates had a multidrug-resistant profile and carried the mecA gene. Most isolates showed resistance to erythromycin, clindamycin, penicillin, tetracycline, ciprofloxacin and fusidic acid and harbored the ermA, ermB, ermC, mphC tetK, tetL, tetM and tetO genes. This study showed a frequent occurrence of multidrug resistance in MRCoNS isolated from healthy poultry in Portugal.
Unidades organizacionais
Descrição
Palavras-chave
Contribuidores
Financiadores
Entidade financiadora
Fundação para a Ciência e a Tecnologia
Programa de financiamento
POR_NORTE
Número da atribuição
SFRH/BD/137947/2018