RESUMO
Corynebacterium striatum, a common constituent of the human skin microbiome, is now considered an emerging multidrug-resistant pathogen of immunocompromised and chronically ill patients. However, little is known about the molecular mechanisms in the transition from colonization to the multidrug-resistant (MDR) invasive phenotype in clinical isolates. This study performed a comprehensive pan-genomic analysis of C. striatum, including isolates from "normal skin microbiome" and from MDR infections, to gain insights into genetic factors contributing to pathogenicity and multidrug resistance in this species. For this, three novel genome sequences were obtained from clinical isolates of C. striatum of patients from Brazil, and other 24 complete or draft C. striatum genomes were retrieved from GenBank, including the ATCC6940 isolate from the Human Microbiome Project. Analysis of C. striatum strains demonstrated the presence of an open pan-genome (α = 0.852803) containing 3816 gene families, including 15 antimicrobial resistance (AMR) genes and 32 putative virulence factors. The core and accessory genomes included 1297 and 1307 genes, respectively. The identified AMR genes are primarily associated with resistance to aminoglycosides and tetracyclines. Of these, 66.6% are present in genomic islands, and four AMR genes, including aac(6')-ib7, are located in a class 1-integron. In conclusion, our data indicated that C. striatum possesses genomic characteristics favorable to the invasive phenotype, with high genomic plasticity, a robust genetic arsenal for iron acquisition, and important virulence determinants and AMR genes present in mobile genetic elements.
Assuntos
Antibacterianos , Corynebacterium , Humanos , Fenótipo , Fatores de Virulência/genética , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade MicrobianaRESUMO
Corynebacterium striatum, a bacterium that is part of the normal skin microbiota, is also an opportunistic pathogen. In recent years, reports of infections and in-hospital and nosocomial outbreaks caused by antimicrobial multidrug-resistant C. striatum strains have been increasing worldwide. However, there are no studies about the genomic determinants related to antimicrobial resistance in C. striatum. This review updates global information related to antimicrobial resistance found in C. striatum and highlights the essential genomic aspects in its persistence and dissemination. The resistome of C. striatum comprises chromosomal and acquired elements. Resistance to fluoroquinolones and daptomycin are due to mutations in chromosomal genes. Conversely, resistance to macrolides, tetracyclines, phenicols, beta-lactams, and aminoglycosides are associated with mobile genomic elements such as plasmids and transposons. The presence and diversity of insertion sequences suggest an essential role in the expression of antimicrobial resistance genes (ARGs) in genomic rearrangements and their potential to transfer these elements to other pathogens. The present study underlines that the resistome of C. striatum is dynamic; it is in evident expansion and could be acting as a reservoir for ARGs.
Assuntos
Antibacterianos/farmacologia , Infecções por Corynebacterium/tratamento farmacológico , Corynebacterium/efeitos dos fármacos , Corynebacterium/genética , Farmacorresistência Bacteriana Múltipla/genética , Sequências Repetitivas Dispersas , Infecções por Corynebacterium/genética , Infecções por Corynebacterium/microbiologia , HumanosRESUMO
Corynebacterium striatum is part of microbiota of skin and nasal mucosa of humans and has been increasingly reported as the etiologic agent of community-acquired and nosocomial diseases. Antimicrobial multidrug-resistant (MDR) C. striatum strains have been increasingly related to various nosocomial diseases and/or outbreaks worldwide, including fatal invasive infections in immunosuppressed and immunocompetent patients. Although cases of infections by C. striatum still neglected in some countries, the improvement of microbiological techniques and studies led to the increase of survival of patients with C. striatum nosocomial infections at different levels of magnitude. Biofilm formation on abiotic surfaces contributes for the persistence of virulent C. striatum and dissemination of antimicrobial resistance in hospital environment. Besides that, empirical antibiotic therapy can select multi-resistant strains and transfer intra and interspecies genes horizontally. In this study, a worldwide survey of C. striatum human infections and nosocomial outbreaks was accomplished by the analysis of clinical-epidemiological and microbiological features of reported cases from varied countries, during a 44-year period (1976-2020).
Assuntos
Antibacterianos/farmacologia , Infecções por Corynebacterium/microbiologia , Corynebacterium/patogenicidade , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Corynebacterium/efeitos dos fármacos , Infecções por Corynebacterium/epidemiologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Humanos , VirulênciaRESUMO
BACKGROUND: Corynebacterium striatum is an emerging multidrug-resistant (MDR) pathogen associated with immunocompromised and chronically ill patients, as well as nosocomial outbreaks. In this study, we characterized 23 MDR C. striatum isolated of bloodstream and catheter-related infections from a hospital of Rio de Janeiro. METHODS: C. striatum isolates were identified by 16S rRNA and rpoB genes sequencing. The dissemination of these isolates was accomplished by pulsed-field gel electrophoresis (PFGE). All isolates were submitted to antimicrobial susceptibility testing by disk diffusion and by minimum inhibitory concentration using E-test strips methods. Antimicrobial resistance genes were detected by polymerase chain reaction. Quantitative tests were performed on four different abiotic surfaces and the ability to produce biofilm on the surface of polyurethane and silicone catheter was also demonstrated by scanning electron microscopy. RESULTS: Eleven PFGE profiles were found. The PFGE profile I was the most frequently observed among isolates. Five different MDR profiles were found and all PFGE profile I isolates presented susceptibility only to tetracycline, vancomycin, linezolid and daptomycin. Only the multidrug-susceptible isolate did not show mutations in the quinolone-resistance determinant region (QRDR) of the gyrA gene and was negative in the search of genes encoding antibiotic resistance. The other 22 isolates were positive to resistance genes to aminoglycoside, macrolides/lincosamides and chloramphenicol and showed mutations in the QRDR of the gyrA gene. Scanning electron microscopy illustrated the ability of MDR blood isolate partaker of the epidemic clone (PFGE profile I) to produce mature biofilm on the surface of polyurethane and silicone catheter. CONCLUSIONS: Genotyping analysis by PFGE revealed the permanence of the MDR PFGE profile I in the nosocomial environment. Other new PFGE profiles emerged as etiologic agents of invasive infections. However, the MDR PFGE profile I was also found predominant among patients with hematogenic infections. The high level of multidrug resistance associated with biofilm formation capacity observed in MDR C. striatum is a case of concern.
Assuntos
Bacteriemia/microbiologia , Biofilmes/crescimento & desenvolvimento , Infecções Relacionadas a Cateter/microbiologia , Infecções por Corynebacterium/microbiologia , Corynebacterium/fisiologia , Surtos de Doenças , Antibacterianos/farmacologia , Bacteriemia/epidemiologia , Proteínas de Bactérias/genética , Infecções Relacionadas a Cateter/epidemiologia , Corynebacterium/efeitos dos fármacos , Corynebacterium/genética , Infecções por Corynebacterium/epidemiologia , Infecção Hospitalar , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Feminino , Técnicas de Genotipagem , Humanos , Masculino , Testes de Sensibilidade Microbiana , RNA Bacteriano/genética , RNA Ribossômico 16S/genéticaRESUMO
Ceratitis capitata (medfly) is a globally important horticultural pest that can be controlled using the sterile insect technique (SIT), but the success of SIT depends on the sexual performance of mass-reared males when released into the field. We added guarana (Paullinia cupana) powder (derived from an Amazonian fruit that is considered to be a stimulant with aphrodisiac effects, capable of improving human physical stamina) to the diets of adult male medflies to determine whether it increased their sexual performance. The basic diet of a protein extract + sucrose (1:3) was enriched with guarana powder (3 % on a volume basis). Experiments examining sexual competitiveness were performed using lab-reared males fed with the enriched diet vs. lab-reared males fed on the basic diet (and lab-reared females fed on the basic diet), as well as lab-reared males fed with the enriched diet vs. wild males fed on the basic diet (and wild females fed on the basic diet). The results of both experiments indicated that males maintained on diets enriched with guarana powder showed higher copulation successes than males fed only with the basic diet. Guarana powder therefore contributed to the greater mating success of lab-reared males (probably because of its stimulant properties), and may represent a new and viable option for increasing SIT effectiveness.(AU)
Assuntos
Animais , Ceratitis capitata , Dieta/veterinária , Paullinia , Infertilidade/veterinária , Insetos , Comportamento Sexual Animal , Reprodução , TephritidaeRESUMO
Ceratitis capitata (medfly) is a globally important horticultural pest that can be controlled using the sterile insect technique (SIT), but the success of SIT depends on the sexual performance of mass-reared males when released into the field. We added guarana (Paullinia cupana) powder (derived from an Amazonian fruit that is considered to be a stimulant with aphrodisiac effects, capable of improving human physical stamina) to the diets of adult male medflies to determine whether it increased their sexual performance. The basic diet of a protein extract + sucrose (1:3) was enriched with guarana powder (3 % on a volume basis). Experiments examining sexual competitiveness were performed using lab-reared males fed with the enriched diet vs. lab-reared males fed on the basic diet (and lab-reared females fed on the basic diet), as well as lab-reared males fed with the enriched diet vs. wild males fed on the basic diet (and wild females fed on the basic diet). The results of both experiments indicated that males maintained on diets enriched with guarana powder showed higher copulation successes than males fed only with the basic diet. Guarana powder therefore contributed to the greater mating success of lab-reared males (probably because of its stimulant properties), and may represent a new and viable option for increasing SIT effectiveness.
Assuntos
Animais , Ceratitis capitata , Dieta/veterinária , Infertilidade/veterinária , Paullinia , Comportamento Sexual Animal , Insetos , Reprodução , TephritidaeRESUMO
Corynebacterium striatum is a potentially pathogenic microorganism that causes nosocomial outbreaks. However, little is known about its virulence factors that may contribute to healthcare-associated infections (HAIs). We investigated the biofilm production on abiotic surfaces of multidrug-resistant (MDR) and multidrug-susceptible (MDS) strains of C. striatum of pulsed-field gel electrophoresis types I-MDR, II-MDR, III-MDS and IV-MDS isolated during a nosocomial outbreak in Rio de Janeiro, Brazil. The results showed that C. striatum was able to adhere to hydrophilic and hydrophobic abiotic surfaces. The C. striatum 1987/I-MDR strain, predominantly isolated from patients undergoing endotracheal intubation procedures, showed the greatest ability to adhere to all surfaces. C. striatum bound fibrinogen to its surface, which contributed to biofilm formation. Scanning electron microscopy showed the production of mature biofilms on polyurethane catheters by all pulsotypes. In conclusion, biofilm production may contribute to the establishment of HAIs caused by C. striatum.
Assuntos
Biofilmes/efeitos dos fármacos , Infecções Relacionadas a Cateter/microbiologia , Infecções por Corynebacterium/microbiologia , Corynebacterium/fisiologia , Infecção Hospitalar/microbiologia , Surtos de Doenças , Farmacorresistência Bacteriana Múltipla , Adulto , Antibacterianos/farmacologia , Aderência Bacteriana/fisiologia , Brasil/epidemiologia , Infecções Relacionadas a Cateter/epidemiologia , Corynebacterium/classificação , Corynebacterium/ultraestrutura , Infecções por Corynebacterium/epidemiologia , Infecção Hospitalar/epidemiologia , Eletroforese em Gel de Campo Pulsado , Equipamentos e Provisões , Feminino , Fibrinogênio/farmacologia , Vidro , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Poliuretanos , Fatores de VirulênciaRESUMO
Corynebacterium striatum is a potentially pathogenic microorganism that causes nosocomial outbreaks. However, little is known about its virulence factors that may contribute to healthcare-associated infections (HAIs). We investigated the biofilm production on abiotic surfaces of multidrug-resistant (MDR) and multidrug-susceptible (MDS) strains of C. striatum of pulsed-field gel electrophoresis types I-MDR, II-MDR, III-MDS and IV-MDS isolated during a nosocomial outbreak in Rio de Janeiro, Brazil. The results showed that C. striatum was able to adhere to hydrophilic and hydrophobic abiotic surfaces. The C. striatum 1987/I-MDR strain, predominantly isolated from patients undergoing endotracheal intubation procedures, showed the greatest ability to adhere to all surfaces. C. striatum bound fibrinogen to its surface, which contributed to biofilm formation. Scanning electron microscopy showed the production of mature biofilms on polyurethane catheters by all pulsotypes. In conclusion, biofilm production may contribute to the establishment of HAIs caused by C. striatum.