RESUMEN
Bioremediation of surfactants in water bodies holds significant ecological importance as they are contaminants of emerging concern posing substantial threats to the aquatic environment. Microbes exhibiting special ability in terms of bioremediation of contaminants have always been reported to thrive in extraordinary environmental conditions that can be extreme in terms of temperature, lack of nutrients, and salinity. Therefore, in the present investigation, a total of 46 bacterial isolates were isolated from the Indian sector of the Southern Ocean and screened for degradation of sodium dodecyl sulphate (SDS). Further, two Gram-positive psychrotolerant bacterial strains, ASOI-01 and ASOI-02 were identified with significant SDS degradation potential. These isolates were further studied for growth optimization under different environmental conditions. The strains were characterized as Staphylococcus saprophyticus and Bacillus pumilus based on morphological, biochemical, and molecular (16S RNA gene) characteristics. The study reports 88.9% and 93.4% degradation of SDS at a concentration of 100 mgL-1, at 20 °C, and pH 7 by S. saprophyticus ASOI-01 and B. pumilus ASOI-02, respectively. The experiments were also conducted in wastewater samples where a slight reduction in degradation efficiency was observed with strains ASOI-01 and ASOI-02 exhibiting 76.83 and 64.93% degradation of SDS respectively. This study infers that these bacteria can be used for the bioremediation of anionic surfactants from water bodies and establishes the potential of extremophilic microbes for the utilization of sustainable wastewater management.
Asunto(s)
Bacillus pumilus , Biodegradación Ambiental , Agua de Mar , Dodecil Sulfato de Sodio , Staphylococcus saprophyticus , Dodecil Sulfato de Sodio/metabolismo , Bacillus pumilus/genética , Bacillus pumilus/metabolismo , Bacillus pumilus/aislamiento & purificación , Bacillus pumilus/clasificación , Staphylococcus saprophyticus/genética , Staphylococcus saprophyticus/aislamiento & purificación , Staphylococcus saprophyticus/metabolismo , Staphylococcus saprophyticus/clasificación , Agua de Mar/microbiología , Tensoactivos/metabolismo , Filogenia , ARN Ribosómico 16S/genética , Contaminantes Químicos del Agua/metabolismo , Aguas Residuales/microbiologíaRESUMEN
AIM: To compare two identification methods for coagulase-negative staphylococci (CoNS) isolated from patients with urinary tract infections, VITEK® 2 and MALDI-TOF VITEK®MS, with genotypic identification by internal transcribed spacer PCR (ITS-PCR). RESULTS: A total of 217 CoNS isolates were studied. Agreement of the VITEK® 2 system with ITS-PCR was 84.8%, with 98% sensitivity and 100% specificity. Thirty-one of the 33 strains incorrectly identified by VITEK® 2 belonged to the species Staphylococcus saprophyticus. MALDI-TOF VITEK®MS showed an excellent correlation with ITS-PCR since it correctly identified all CoNS isolates. CONCLUSION: MALDI-TOF VITEK®MS is more accurate than the automated VITEK® 2 system in identifying CoNS isolated from urinary tract infections to species level, particularly urinary isolates of S. saprophyticus.
Asunto(s)
ADN Bacteriano/genética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Infecciones Estafilocócicas/microbiología , Staphylococcus saprophyticus/aislamiento & purificación , Infecciones Urinarias/microbiología , Cartilla de ADN/genética , Humanos , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , ARN Ribosómico 16S/genética , ARN Ribosómico 23S/genética , Sensibilidad y Especificidad , Infecciones Estafilocócicas/orina , Staphylococcus saprophyticus/genética , Infecciones Urinarias/orinaRESUMEN
Staphylococcus saprophyticus is an important pathogen responsible for community urinary tract infections (UTI). Besides composing the human microbiota, this species is widely distributed in the environment and the origins of this organism for human infection is not fully characterized. Although some virulence determinants are known, such as d-serine deaminase (DsdA), urease and cell-wall associated proteins, few studies investigated the distribution of virulence-associated genes and analyzed the pathogenic potential of S. saprophyticus strains from different sources. The aim of the present study was to detect the presence of S. saprophyticus genes encoding surface proteins UafA, Aas, Ssp, SdrI, SssF as well as the DsdA and urease enzymes. A total of 142 S. saprophyticus strains were obtained from four sources: UTI, colonization, water and food. It was found, in every tested strain, the presence of genes encoding the surface proteins UafA, Aas, Ssp and SssF and the DsdA and urease enzymes. In contrast, the gene encoding SdrI surface protein was not detected in any of the strains of S. saprophyticus. These results provide a better understanding of the characteristics of S. saprophyticus strains and suggest that isolates from non-human sources have a potential to colonize the urinary tract.
Asunto(s)
Proteínas Bacterianas/genética , Genes Bacterianos/genética , Infecciones Estafilocócicas/microbiología , Staphylococcus saprophyticus/genética , Staphylococcus saprophyticus/aislamiento & purificación , Factores de Virulencia/genética , Brasil , ADN Bacteriano/aislamiento & purificación , Femenino , Humanos , Hidroliasas/genética , Proteínas de la Membrana/genética , Staphylococcus saprophyticus/enzimología , Staphylococcus saprophyticus/patogenicidad , Ureasa/genética , Sistema Urinario/microbiología , Infecciones Urinarias/microbiología , Virulencia/genéticaRESUMEN
INTRODUCTION: Bovine mastitis causes important economic losses in the dairy industry. Coagulase-negative staphylococci (CNS) are a group of bacteria commonly isolated from bovine mastitis and can display resistance to a wide range of antimicrobial agents. OBJECTIVES: The objective of this study was to determine staphylococcal resistance towards ß-lactam, macrolide and lincosamide antimicrobials in quarters previously treated with third-generation cephalosporin and after lincosamide intramammary therapy. METHODS: Sick quarters of eighteen cows from Villaguay, Entre Ríos (Argentina) with clinical mastitis were studied. All staphylococcal isolates were tested by disk diffusion for their antimicrobial susceptibilities. Cefoxitin resistance was investigated by PCR and sequencing for both the mecA and mecC genes. RESULTS: Resistances to penicillin, oxacillin and cefoxitin were observed, whereas no resistance to macrolide and lincosamide was detected. A cefoxitin-resistant Staphylococcus saprophyticus was found to be mecA-negative but mecC-positive. CONCLUSIONS: This study reports for the first time the mecC gene from a CNS in bovine mastitis in South America. Because CNS may act as reservoirs of antimicrobial resistance genes, they can be seen as a potential public health threat with respect to antimicrobial resistance and the development of multiple resistance. Also, the emergence of methicillin-resistant phenotypes will limit therapeutic options.
Asunto(s)
Antibacterianos/farmacología , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana , Mastitis Bovina/microbiología , Infecciones Estafilocócicas/veterinaria , Staphylococcus saprophyticus/aislamiento & purificación , Animales , Argentina , Bovinos , Cefoxitina/farmacología , Femenino , Lincosamidas/farmacología , Macrólidos/farmacología , Pruebas de Sensibilidad Microbiana , Análisis de Secuencia de ADN , Staphylococcus saprophyticus/efectos de los fármacos , Staphylococcus saprophyticus/genética , beta-Lactamas/farmacologíaRESUMEN
Staphylococcus saprophyticus is an uropathogen belonging to the human microbiota and is responsible for community-acquired infections of the urinary tract. Identification of Staphylococcus species by biochemical tests is laborious and costly when compared to routine laboratory tests. Because of their high sensitivity and specificity, molecular methods are better suited for accurate identification of Staphylococcusspp. Therefore, the goal of this work was to standardize a polymerase chain reaction (PCR) protocol using species-specific primers, based on the heat-shock repressor coding hrcA gene, for the identification of S.saprophyticus. A total of 142 S. saprophyticus strains were obtained from different sources, including clinical, environmental, and foodborne strains. We also included 98 strains of Staphylococcus spp. to further validate the proposed method. Reliable results for the detection of S. saprophyticus isolates were obtained for 100% of the strains evaluated. The results were in accordance with matrix-assisted laser desorption ionization-time of flight mass spectrometry identification, thus highlighting the applicability of species-specific PCR for the molecular identification of S. saprophyticus.
Asunto(s)
Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena de la Polimerasa/métodos , Proteínas Represoras/genética , Staphylococcus saprophyticus/clasificación , Staphylococcus saprophyticus/aislamiento & purificación , Microbiología Ambiental , Femenino , Microbiología de Alimentos , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/microbiología , Sensibilidad y Especificidad , Infecciones Estafilocócicas/microbiología , Staphylococcus saprophyticus/genética , Infecciones Urinarias/microbiologíaRESUMEN
OBJECTIVE: To analyze and compare the etiological uropathogens and the susceptibility profile findings on urine culture between sporadic cases of community-acquired, uncomplicated urinary tract infection (UTI) and recurrent UTI cases in women. MATERIALS AND METHODS: We retrospectively analyzed the clinical data of 1629 women with uncomplicated UTI evaluated at our hospital between January 2007 and December 2012. Patients were divided into 2 groups: (1) no recurrent UTI and (2) recurrent UTI. We analyzed the microbiological findings and compared susceptibility profiles between groups. RESULTS: A total of 420 women were included. Group 1 had 233 (55.5%) patients and group 2 had 187 (44.5%). Escherichia coli was the most common agent in both groups (76.4% and 74.3%, respectively; P = .625), whereas Staphylococcus saprophyticus (8.2%) was the second most common in group 1, and Enterococcus faecalis was the second most common in group 2 (8.0%). Nitrofurantoin was the only oral agent that maintained the susceptibility profile in both groups (87.1% and 88.7%, respectively; P = .883). For E coli infections, only nitrofurantoin and amoxicillin/clavulanate maintained susceptibility rates more than 90% in both groups. CONCLUSION: UTI episodes in patients with recurrent UTI had similar bacterial spectra, but different susceptibility profiles compared with those from patients with nonrecurrent infections. The susceptibility rate for nitrofurantoin in patients with recurrent UTI remained high and comparable to the observed in patients with sporadic UTI, reinforcing its indication for empirical treatment while waiting for urine culture results.
Asunto(s)
Antiinfecciosos Urinarios/uso terapéutico , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Farmacorresistencia Bacteriana , Enterococcus faecalis/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Femenino , Humanos , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Nitrofurantoína/uso terapéutico , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Staphylococcus saprophyticus/aislamiento & purificación , Adulto JovenRESUMEN
Staphylococcus saprophyticus is a rarely reported agent of urinary tract infection (UTI) in the pediatric population. In our retrospective 3-year study, S. saprophyticus comprised 24.5% of 106 isolates of UTIs in female adolescents 12-15 years of age who attended an emergency department. Clinicians should be aware of the high prevalence of this etiology when empirically treating UTIs in female adolescents.
Asunto(s)
Infecciones Estafilocócicas/epidemiología , Staphylococcus saprophyticus/aislamiento & purificación , Infecciones Urinarias/epidemiología , Infecciones Urinarias/microbiología , Adolescente , Niño , Femenino , Humanos , Prevalencia , Estudios RetrospectivosRESUMEN
The epidemiology of urinary tract infections (UTI) by Staphylococcus saprophyticus has not been fully characterised and strain typing methods have not been validated for this agent. To evaluate whether epidemiological relationships exist between clusters of pulsed field gel-electrophoresis (PFGE) genotypes of S. saprophyticus from community-acquired UTI, a cross-sectional surveillance study was conducted in the city of Rio de Janeiro, Brazil. In total, 32 (16%) female patients attending two walk-in clinics were culture-positive for S. saprophyticus. Five PFGE clusters were defined and evaluated against epidemiological data. The PFGE clusters were grouped in time, suggesting the existence of community point sources of S. saprophyticus. From these point sources, S. saprophyticus strains may spread among individuals.
Asunto(s)
Infecciones Estafilocócicas/microbiología , Staphylococcus saprophyticus/aislamiento & purificación , Infecciones Urinarias/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Técnicas de Tipificación Bacteriana , Brasil/epidemiología , Niño , Preescolar , Análisis por Conglomerados , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Estudios Transversales , Electroforesis en Gel de Campo Pulsado , Femenino , Humanos , Lactante , Persona de Mediana Edad , Vigilancia de la Población , Embarazo , Infecciones Estafilocócicas/epidemiología , Staphylococcus saprophyticus/clasificación , Infecciones Urinarias/epidemiología , Adulto JovenRESUMEN
The epidemiology of urinary tract infections (UTI) by Staphylococcus saprophyticus has not been fully characterised and strain typing methods have not been validated for this agent. To evaluate whether epidemiological relationships exist between clusters of pulsed field gel-electrophoresis (PFGE) genotypes of S. saprophyticus from community-acquired UTI, a cross-sectional surveillance study was conducted in the city of Rio de Janeiro, Brazil. In total, 32 (16%) female patients attending two walk-in clinics were culture-positive for S. saprophyticus. Five PFGE clusters were defined and evaluated against epidemiological data. The PFGE clusters were grouped in time, suggesting the existence of community point sources of S. saprophyticus. From these point sources, S. saprophyticus strains may spread among individuals.
Asunto(s)
Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Persona de Mediana Edad , Embarazo , Adulto Joven , Infecciones Estafilocócicas/microbiología , Staphylococcus saprophyticus/aislamiento & purificación , Infecciones Urinarias/microbiología , Técnicas de Tipificación Bacteriana , Brasil/epidemiología , Análisis por Conglomerados , Estudios Transversales , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Electroforesis en Gel de Campo Pulsado , Vigilancia de la Población , Infecciones Estafilocócicas/epidemiología , Staphylococcus saprophyticus/clasificación , Infecciones Urinarias/epidemiologíaRESUMEN
The emergence of Staphylococcus spp. not only as human pathogens, but also as reservoirs of antibiotic resistance determinants, requires the development of methods for their rapid and reliable identification in medically important samples. The aim of this study was to compare three phenotypic methods for the identification of Staphylococcus spp. isolated from patients with urinary tract infection using the PCR of the 16S-23S interspace region generating molecular weight patterns (ITR-PCR) as reference. All 57 S. saprophyticus studied were correctly identified using only the novobiocin disk. A rate of agreement of 98.0% was obtained for the simplified battery of biochemical tests in relation to ITR-PCR, whereas the Vitek I system and novobiocin disk showed 81.2% and 89.1% agreement, respectively. No other novobiocin-resistant non-S. saprophyticus strain was identified. Thus, the novobiocin disk is a feasible alternative for the identification of S. saprophyticus in urine samples in laboratories with limited resources. ITR-PCR and the simplified battery of biochemical tests were more reliable than the commercial systems currently available. This study confirms that automated systems are still unable to correctly differentiate CoNS species and that simple, reliable and inexpensive methods can be used for routine identification.
Asunto(s)
Bioquímica/métodos , ADN Espaciador Ribosómico/genética , Reacción en Cadena de la Polimerasa/métodos , ARN Ribosómico 16S/genética , ARN Ribosómico 23S/genética , Infecciones Estafilocócicas/microbiología , Staphylococcus saprophyticus/aislamiento & purificación , Infecciones Urinarias/microbiología , Antibacterianos/farmacología , ADN Bacteriano/genética , Farmacorresistencia Bacteriana , Humanos , Staphylococcus saprophyticus/clasificación , Staphylococcus saprophyticus/efectos de los fármacos , Staphylococcus saprophyticus/genéticaRESUMEN
BACKGROUND: Staphylococcus saprophyticus is the second most frequent community-acquired causative agent of urinary tract infection (UTI). The objective of this study was to evaluate the susceptibility profile and resistance detection in Staphylococcus species. isolated from patients with UTI. MATERIALS AND METHODS: The isolates were investigated using the disk diffusion method, Vitek I system, E-test®, and detection of the mecA gene. RESULTS: Most isolates (76.2%) were resistant to oxacillin by the disk diffusion method, followed by those resistant to penicillin (72.2%). The oxacillin disk diffusion method, E-test, and Vitek I method showed higher sensitivity (94.4%) and lower specificity (28.9, 26.5, and 24.0%, respectively) than the cefoxitin disk diffusion test (sensitivity: 83.5%, specificity: 85.5%) for the detection of oxacillin resistance. CONCLUSIONS: The large number of oxacillin-resistant isolates indicates that the breakpoint value recommended by the Clinical and Laboratory Standards Institute may overestimate oxacillin resistance in S. saprophyticus. Thus, changes in these guidelines are necessary for the correct detection of this resistance.