RESUMEN
A bacterium designated as strain STP14 was isolated from a sewage treatment plant and identified as Acinetobacter calcoaceticus based on 16S ribosomal RNA gene sequencing. Strain STP14 exhibited resistance to several metals such as mercury, cobalt, copper, nickel, lead, and cadmium. Among these metals, the bacterium showed maximum resistance to cadmium in concentration up to 1200 mg/L. The antimicrobial susceptibility test of A. calcoaceticus strain STP14 showed coresistance to all tested antibiotics except tigecycline and chloramphenicol for which 16 ± 1- and 15 ± 1-mm zone of inhibition was observed, respectively. The protein pattern of the crude cellular extract revealed substantial differences in protein bands of untreated control and cadmium treated A. calcoaceticus strain STP14 suggesting variable protein expression under cadmium stress. Metals and antibiotic resistance are increasing phenomenon and universal concern of public health. This study improves our understanding regarding the bacterial coresistance against metals and antibiotics and the possible emergence of multidrug resistance due to selective pressure and coselection in the metal polluted sewage sludge.
Asunto(s)
Acinetobacter calcoaceticus/efectos de los fármacos , Acinetobacter calcoaceticus/genética , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Metales Pesados/toxicidad , Aguas del Alcantarillado/microbiología , Acinetobacter calcoaceticus/aislamiento & purificación , Metales Pesados/análisis , Pruebas de Sensibilidad Microbiana , Aguas del Alcantarillado/química , Purificación del Agua/métodosRESUMEN
BACKGROUND: Multidrug-resistant (MDR) Acinetobacter calcoaceticus-Acinetobacter baumannii (Acb) complex has become an important cause of nosocomial pneumonia. Sulbactam is a ß-lactamase inhibitor with antimicrobial activity against MDR Acb complex. METHODS: To investigate outcomes of pneumonia involving MDR Acb complex treated with sulbactam or ampicillin/sulbactam for at least 7 days, we conducted a retrospective study of 173 adult patients over a 34 month period. RESULTS: Of 173 patients, 138 (79.8%) received combination therapy, mainly with carbapenems (119/138, 86.2%). The clinical response rate was 67.6% and the 30 day mortality rate was 31.2%. The independent predictors of clinical failure were malignancy, bilateral pneumonia and shorter duration of treatment. In patients with sulbactam-susceptible strains, there was no difference in clinical and microbiological outcome between combination therapy and monotherapy. Compared to the sulbactam-susceptible group, the sulbactam-resistant group had a lower rate of airway eradication, a longer duration of treatment and a higher rate of combination therapy with predominantly carbapenems (p < 0.05). There was no significant difference between the two groups in clinical resolution and 30 day mortality rates. CONCLUSIONS: Sulbactam could be a treatment option for pneumonia involving MDR Acb complex, and combination therapy with carbapenems could be considered for sulbactam-resistant cases.
Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Acinetobacter calcoaceticus/efectos de los fármacos , Antibacterianos/uso terapéutico , Neumonía Bacteriana/tratamiento farmacológico , Sulbactam/uso terapéutico , Infecciones por Acinetobacter , Acinetobacter baumannii/aislamiento & purificación , Acinetobacter calcoaceticus/aislamiento & purificación , Adulto , Anciano , Ampicilina/administración & dosificación , Ampicilina/uso terapéutico , Carbapenémicos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Quimioterapia Combinada , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Neumonía Bacteriana/microbiología , Estudios Retrospectivos , Sulbactam/administración & dosificación , Taiwán , Factores de TiempoAsunto(s)
Infecciones por Acinetobacter/tratamiento farmacológico , Acinetobacter calcoaceticus/aislamiento & purificación , Antibacterianos/uso terapéutico , Ciprofloxacina/uso terapéutico , Endoftalmitis/tratamiento farmacológico , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Infecciones por Acinetobacter/microbiología , Humor Acuoso/microbiología , Endoftalmitis/microbiología , Infecciones Bacterianas del Ojo/microbiología , Humanos , Cuerpo Vítreo/microbiologíaAsunto(s)
Infecciones por Acinetobacter/veterinaria , Acinetobacter calcoaceticus/aislamiento & purificación , Antiinfecciosos/uso terapéutico , Fluoroquinolonas , Enfermedades de los Genitales Masculinos/veterinaria , Enfermedades de los Caballos/tratamiento farmacológico , Quinolonas/uso terapéutico , Vesículas Seminales , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/cirugía , Animales , Antiinfecciosos/efectos adversos , Enrofloxacina , Enfermedades de los Genitales Masculinos/tratamiento farmacológico , Enfermedades de los Genitales Masculinos/cirugía , Enfermedades de los Caballos/cirugía , Caballos , Masculino , Quinolonas/efectos adversos , Semen/microbiología , Vesículas Seminales/microbiología , Vesículas Seminales/patología , Vesículas Seminales/cirugía , Resultado del TratamientoRESUMEN
Twenty bacterial strains were isolated from a sample of contaminated heating oil and screened for their ability to use petroleum and several common fuels as the sole source of carbon and energy. One of the isolates, named MM5, was able to grow on petroleum derivatives and brought about an emulsification of those compounds. Gas chromatography studies showed that strain MM5 was able to degrade hydrocarbons of heating oil. MM5 has been tentatively identified as a strain of Acinetobacter calcoaceticus. The fine structure of MM5 was examined by transmission electron microscopy. Incubation in the presence of hydrocarbon substrates resulted in the development of intracellular electron-transparent inclusions. These structures were absent in the non-hydrocarbon cultures studied.