RESUMO
We characterized a multidrug-resistant (MDR) Enterobacter spp. isolate highlighting the genetic aspects of the antimicrobial resistance genes. An Enterobacter spp. isolate (Ec61) was recovered in 2014 from a transtracheal aspirate sample from a patient admitted to a Brazilian tertiary hospital and submitted to further microbiological and genomic characterization. Ec61 was identified as Enterobacter hormaechei subsp. xiangfangensis strain ST451, showing an MDR profile and the presence of genes codifying the new ß-lactamase variants BKC-2 and ACT-84 and the mobile colistin resistance gene mcr-9.1.
Assuntos
Colistina , Enterobacter , Antibacterianos/farmacologia , Brasil , Colistina/farmacologia , Enterobacter/genética , Humanos , Plasmídeos , beta-Lactamases/genéticaRESUMO
ABSTRACT Due to the emergence of multi-drug resistant bacteria, and the evident limitation in therapeutic options, alternatives to combat bacterial infections have been sought. One of these is phage therapy, which is the use of bacterial viruses to kill pathogenic bacteria responsible for the infection. These viruses called bacteriophages are very abundant organisms in the world and are harmless to humans. There are several advantages in using phage therapy, especially against multi-drug resistant pathogens, which tend to be dominated by individual strains. The advantages include fewer collateral effects such as lower disturbance of gut microbiota and less antimicrobials consumption, which itself leads to reducing antibiotic resistance rates. Unfortunately, few clinical studies have been initiated in Brazil and this area is little explored in our country. This manuscript describes clinical evidence of successful phage utilization on pathogens considered a threat in Brazil, highlighting the benefits of a possible phage utilization as an important tool to combat antimicrobial resistance in our country.
RESUMO
Due to the emergence of multi-drug resistant bacteria, and the evident limitation in therapeutic options, alternatives to combat bacterial infections have been sought. One of these is phage therapy, which is the use of bacterial viruses to kill pathogenic bacteria responsible for the infection. These viruses called bacteriophages are very abundant organisms in the world and are harmless to humans. There are several advantages in using phage therapy, especially against multi-drug resistant pathogens, which tend to be dominated by individual strains. The advantages include fewer collateral effects such as lower disturbance of gut microbiota and less antimicrobials consumption, which itself leads to reducing antibiotic resistance rates. Unfortunately, few clinical studies have been initiated in Brazil and this area is little explored in our country. This manuscript describes clinical evidence of successful phage utilization on pathogens considered a threat in Brazil, highlighting the benefits of a possible phage utilization as an important tool to combat antimicrobial resistance in our country.
Assuntos
Bacteriófagos , Farmacorresistência Bacteriana/genética , Terapia por Fagos , Antibacterianos , Infecções Bacterianas , Brasil , HumanosAssuntos
Humanos , Feminino , Pré-Escolar , beta-Lactamases/metabolismo , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Paquistão , beta-Lactamases/genética , Testes de Sensibilidade Microbiana , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Antibacterianos/farmacologiaAssuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli/isolamento & purificação , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Pré-Escolar , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Feminino , Humanos , Testes de Sensibilidade Microbiana , Paquistão , beta-Lactamases/genéticaRESUMO
Miniature inverted repeat transposable elements (MITEs) have been identified flanking class 1 integrons. We have identified and characterized a 439-bp MITE-like structure in seven Acinetobacter species isolates from Portugal and Brazil. The complete sequence similarity of the elements and flanking regions suggests that MITEs may act as mobilizable vectors for the dissemination of integrons.
Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter/genética , Elementos de DNA Transponíveis , Integrons , Sequências Repetidas Invertidas , Acinetobacter/isolamento & purificação , Brasil , DNA Bacteriano/química , DNA Bacteriano/genética , Transferência Genética Horizontal , Humanos , Dados de Sequência Molecular , Portugal , Análise de Sequência de DNAAssuntos
Pseudomonas aeruginosa/metabolismo , beta-Lactamases/metabolismo , Adulto , Brasil , Pré-Escolar , DNA Bacteriano/genética , Eletroforese em Gel de Campo Pulsado , Europa (Continente) , Feminino , Humanos , Leucemia/microbiologia , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ferimentos e Lesões/microbiologiaRESUMO
Seven bla(IMP-1)-harboring Acinetobacter sp. isolates and one Pseudomonas putida clinical isolate were recovered from hospitalized patients. All isolates possessed a class 1 integron, named In86, carrying the same cassette array [bla(IMP1), aac(6')-31, and aadA1], which was plasmid located in five of the isolates. This report describes the ability of nonfermentative nosocomial pathogens to acquire and disseminate antimicrobial resistance determinants.
Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos , Integrons/genética , Acinetobacter/efeitos dos fármacos , Acinetobacter/genética , Acinetobacter/isolamento & purificação , Acinetobacter/patogenicidade , Sequência de Aminoácidos , Sequência de Bases , Brasil/epidemiologia , Códon de Terminação , Infecção Hospitalar , Transferência Genética Horizontal , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Fases de Leitura Aberta , Plasmídeos/genética , Pseudomonas putida/efeitos dos fármacos , Pseudomonas putida/genética , Pseudomonas putida/isolamento & purificação , Pseudomonas putida/patogenicidade , Transcrição GênicaRESUMO
As part of the SENTRY Antimicrobial Surveillance Program in 2002, five multidrug-resistant Pseudomonas aeruginosa clinical isolates were detected with metallo-beta-lactamase (MbetaL) activity. The isolates were recovered from different patients in a medical center located in Dusseldorf, Germany. The resistant determinant was isolated amplifying the region between the integrase and the aacA4 gene cassette. Sequencing revealed a novel MbetaL gene, designated bla(GIM-1). Additional analysis showed that GIM-1, comprising 250 amino acids and with a pI value of 5.4, differs in its primary sequence from that described for IMP, VIM, and SPM-1 enzymes by 39 to 43%, 28 to 31%, and 28%, respectively. The enzyme possesses unique amino acids within the major consensus sequence (HXHXD) of the MbetaL family. Kinetics analysis revealed that GIM-1 has no clear preference for any substrate and did not hydrolyze azlocillin, aztreonam, and the serine-beta-lactamase inhibitors. bla(GIM-1) was found on a 22-kb nontransferable plasmid. The new MbetaL gene was embedded in the first position of a 6-kb class 1 integron, In77, with distinct features, including an aacA4 cassette downstream of the MbetaL gene that appeared to be truncated with bla(GIM-1). The aacA4 was followed by an aadA1 gene cassette that was interrupted by a copy of the IS1394. This integron also carried an oxacillinase gene, bla(OXA-2), before the 3'-CS region. GIM-1 appears to be a unique MbetaL, which is located in a distinct integron structure, and represents the fourth subclass of mobile MbetaL enzymes to be characterized.
Assuntos
beta-Lactamases/genética , Sequência de Aminoácidos , Carbapenêmicos/farmacologia , Primers do DNA , DNA Bacteriano/genética , Farmacorresistência Bacteriana , Eletroforese em Gel de Ágar , Eletroforese em Gel de Campo Pulsado , Genes Bacterianos/genética , Integrons/genética , Focalização Isoelétrica , Cinética , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Fenótipo , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Since January 2002 Pseudomonas sp. strains resistant to carbapenems and ceftazidime have been routinely screened as part of the SENTRY Antimicrobial Surveillance Program for metallo-beta-lactamase production, and their resistance determinants have been analyzed. Pseudomonas aeruginosa index strain 101-4704, which harbors a novel bla(IMP) variant, bla(IMP-16), was isolated in April 2002 from a 60-year-old man in Brasilia, Brazil. bla(IMP-16) was found on the chromosome of the P. aeruginosa index strain, and the deduced amino acid sequence (IMP-16) showed the greatest identities to IMP-11 (90.3%) and IMP-8 (89.5%). Sequence analysis revealed that bla(IMP-16) was associated with a class 1 integron, which also encoded aminoglycoside-modifying enzymes. Downstream of bla(IMP-16) resided an open reading frame, which consisted of a new aminoglycoside-modifying gene, namely, aac(6')-30, which was fused with aac(6')-Ib'. The amino acid sequence of the aac(6')-30 putative protein showed the most identity (52.7%) to the sequence of AAC(6')-29b described previously. The fourth gene cassette constituted aadA1. The steady-state kinetics of IMP-16 demonstrated that the enzyme preferred cephalosporins and carbapenems to penicillins. The main functional difference observed among the kinetic values for IMP-16 compared to those for other IMPs was a lack of cefoxitin hydrolysis and a lower kcat/Km value for imipenem (0.36 microM(-1) . s(-1)). This report further emphasizes the spread of metallo-beta-lactamase genes and their close association with various aminoglycoside resistance genes.