Asunto(s)
Quemaduras/microbiología , Infecciones por Pseudomonas/diagnóstico , Pseudomonas mendocina/aislamiento & purificación , beta-Lactamasas/genética , Adulto , Quemaduras/cirugía , Colistina/uso terapéutico , Resultado Fatal , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia Multiorgánica/etiología , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas mendocina/genética , Trasplante de Piel , Resultado del TratamientoRESUMEN
The objective of this study was to investigate the molecular mechanisms explaining the multidrug-resistant (MDR) phenotype found in a novel clinical Shewanella sp. strain (Shew256) recovered from a diabetic patient. Whole-genome shotgun sequencing was performed using Illumina MiSeq-I and Nextera XT DNA library. De novo assembly was performed with SPAdes. RAST Server was used to predict the open-reading frames and the predictions were confirmed using BLAST. Further genomic analysis was carried out using average nucleotide identity (ANI), ACT (Artemis), OrthoMCL, ARG-ANNOT, ISfinder, PHAST, tRNAscan-SE, plasmidSPAdes, PlasmidFinder and MAUVE. PCR and plasmid extraction were also performed. Genomic analysis revealed a total of 456 predicted genes unique to Shew256 compared with other Shewanella genomes. Moreover, the presence of different resistance genes, including blaPER-2, was found. A complex class 1 integron containing the ISCR1 gene, disrupted by two putative transposase genes, was identified. Furthermore, other resistance genes, a transposon containing aph(3'), insertion sequences, phages and non-coding RNAs were also found. In conclusion, evidence of acquisition of resistance genes and mobile elements that could explain the MDR phenotype were observed. This Shewanella sp. represents a prime example of how antibiotic resistance determinants can be acquired by uncommon pathogens.
Asunto(s)
Elementos Transponibles de ADN/genética , Farmacorresistencia Bacteriana Múltiple/genética , Genes Bacterianos/genética , Shewanella/enzimología , Shewanella/genética , beta-Lactamasas/genética , Anciano , Antibacterianos/farmacología , ADN Bacteriano/genética , Transferencia de Gen Horizontal , Genoma Bacteriano , Infecciones por Bacterias Gramnegativas/microbiología , Humanos , Integrones , Masculino , Pruebas de Sensibilidad Microbiana , Sistemas de Lectura Abierta , Filogenia , Plásmidos/genética , Factores R/genética , ARN no Traducido , Análisis de Secuencia de ADN , Shewanella/efectos de los fármacos , Shewanella/aislamiento & purificación , Secuenciación Completa del GenomaRESUMEN
A taxonomically unique bacterial strain, Acinetobacter sp. A47, has been recovered from several soft tissue samples from a patient undergoing reconstructive surgery owing to a traumatic amputation. The results of 16S rRNA, rpoB, and gyrB gene comparative sequence analyses showed that A47 does not belong to any of the hitherto-known taxa and may represent an as-yet-unknown Acinetobacter species. The recognition of this novel organism contributes to our knowledge of the taxonomic complexity underlying infections caused by Acinetobacter.
Asunto(s)
Infecciones por Acinetobacter , Acinetobacter/genética , Traumatismos de los Tejidos Blandos , Acinetobacter/clasificación , Acinetobacter/fisiología , Infecciones por Acinetobacter/diagnóstico , Infecciones por Acinetobacter/microbiología , ADN Bacteriano/análisis , ADN Bacteriano/genética , Femenino , Genes Bacterianos/genética , Humanos , Persona de Mediana Edad , Datos de Secuencia Molecular , Fenotipo , Traumatismos de los Tejidos Blandos/diagnóstico , Traumatismos de los Tejidos Blandos/microbiologíaRESUMEN
Acinetobacter baumannii pigmented strains are not common in clinical settings. Here, we report an outbreak caused by indigo-pigmented A. baumannii strains isolated in an acute care hospital in Argentina from March to September 2012. Pan-PCR assays exposed a unique pattern belonging to the recently described regional CC113(B)/CC79(P) clonal complex that confirms the relevant relationships among the indigo-pigmented A. baumannii strains. All of them were extensively drug resistant and harbored different genetic elements associated with horizontal genetic transfer, such as the transposon Tn2006, class 2 integrons, AbaR-type islands, IS125, IS26, strA, strB, florR, and the small recombinase ISCR2 associated with the sul2 gene preceded by ISAba1.
Asunto(s)
Infecciones por Acinetobacter/epidemiología , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/metabolismo , Brotes de Enfermedades , Farmacorresistencia Bacteriana Múltiple , Pigmentos Biológicos/metabolismo , Acinetobacter baumannii/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Animales , Argentina , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , Femenino , Genotipo , Humanos , Secuencias Repetitivas Esparcidas , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Tipificación Molecular , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADNRESUMEN
Herein, we report four cases of Comamonas kerstersii intra-abdominal infections representing the first report of human infections caused by this Comamonas species. In addition, our work demonstrates the association of C. kerstersii with peritonitis secondary to appendix rupture.