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1.
J Glob Antimicrob Resist ; 31: 38-44, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35948241

RESUMEN

OBJECTIVES: In contrast to other qnr families, qnrVC has been reported mainly in Vibrio spp. and inserted in class 1 integrons. This study aimed to identify the variants of qnrVC genes detected in Klebsiella pneumoniae carbapenemase-2-producing Enterobacter and Klebsiella strains isolated from Brazilian coastal waters and the genetic contexts associated with their occurrence. METHODS: qnrVC variants were identified by Sanger sequencing. Stains were typified by pulsed-field gel electrophoresis. Antimicrobial susceptibility testing, conjugation assays, and whole genome sequencing (WGS) were applied to identify the strains' antimicrobial resistance profile, qnrVC and blaKPC-2 co-transference, and qnrVC genetic context. RESULTS: qnrVC1 was identified in 15 Enterobacter and 3 Klebsiella, and qnrVC4 in 2 Enterobacter strains. Pulsed-field gel electrophoresis revealed 12 clonal profiles of Enterobacter and one of Klebsiella. Strains were resistant to aminoglycosides, beta-lactams, fosfomycin, quinolones, and sulfamethoxazole-trimethoprim. Co-transference of qnrVC and blaKPC-2 were obtained from five representative Enterobacter strains, which showed resistance to ampicillin and amoxicillin-clavulanate, and reduced susceptibility to extended-spectrum cephalosporins, meropenem, and ciprofloxacin. WGS analysis from representative strains revealed one K. quasipneumoniae subsp. similipneumoniae, one E. soli, four E. kobei, and seven isolates belonging to Enterobacter Taxon 3. Long-read WGS showed qnrVC and blaKPC-2 were carried by the same replicon on Klebsiella and Enterobacter strains, and the qnrVC association with not previously described genetic environments composed of insertion sequences and truncated genes. These contexts occurred in small- and high-molecular-weight plasmids belonging to IncFII, IncP6, pKPC-CAV1321, and IncU groups. CONCLUSION: Our results suggest that the dissemination of qnrVC among Enterobacterales in Brazilian coastal waters is associated with several genetic recombination events.


Asunto(s)
Enterobacter , Klebsiella , Antibacterianos/farmacología , Enterobacter/genética , Klebsiella/genética , Klebsiella pneumoniae/genética
2.
Arch Microbiol ; 204(1): 14, 2021 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-34894275

RESUMEN

The current knowledge of bean plants microbiome is far from being complete. Unraveling the complexity of the bacterial communities within common bean cultivars that may significantly contribute to plant health, growth and protection against soil pathogens, represents a major challenge. In this study, the richness and composition of the bacterial communities from bean plant rhizospheres and control bulk soils were analyzed by high-throughput sequencing and comparative analyses. From the classified sequences, Proteobacteria represented the most abundant phylum (42-66%), followed by Acidobacteria (12-36%) and Actinobacteria (11-18%), Bacterial community structures were different between bulk soil and rhizosphere samples. Comparing the bean cultivars, the biofortified cultivar presented high number of sequences affiliated to the genera Burkholderia and Rhodanobacter. Interestingly, despite the presence of stable and persistent core bacterial taxa associated with the common bean varieties, our analysis suggested that the biofortified common bean cultivar could select and maintain differential abundances of microbial groups in the rhizosphere environment.


Asunto(s)
Phaseolus , Rizosfera , Bacterias/genética , Plantas , Microbiología del Suelo
3.
Genet Mol Biol ; 43(4): e20200160, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33270074

RESUMEN

Early age acute leukemia (EAL) shows a high frequency of KMT2A-rearrangements (KMT2A-r). Previous investigations highlighted double-strand breaks arising from maternal exposure to xenobiotics during pregnancy as a risk factor for EAL and KMT2A-r. In this case-control study, we investigated the relationship between EAL and genetic variants of the nonhomologous end-joining (XRCC6 rs5751129, XRCC4 rs6869366 and rs28360071), since they might affect DNA repair capacity, leading to KMT2A-r and leukemogenesis. Samples from 577 individuals (acute lymphoblastic leukemia-ALL, n=164; acute myeloid leukemia-AML, n=113; controls, n=300) were genotyped. No significant association was found for rs5751129 and rs6869366, whereas rs28360071 was associated with an increased risk for ALL with KMT2A-r (IIxID: OR - Odds ratio 2.23, CI 1.17-4.25, p=0.014). Bone marrow samples from ALL patients showed a higher expression of XRCC4 compared to AML patients (p=0.025). Human Splicing Finder 3.1 predicted that the deleted allele of rs28360071 is potentially associated with the activation of a 5' cryptic splice site in intron 3 of XRCC4. The sequencing of cDNA did not show any differences on the splicing process for the rs28360071 genotypes. Our results suggest that the deleted allele for rs28360071 increases the risk for ALL with KMT2A-r, but not by modifying the XRCC4 expression levels or its structure.

4.
Zootaxa ; 4442(1): 137-152, 2018 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-30313987

RESUMEN

Two new species of Hemimycale from Southeastern Brazil are described in this study with the use of morphological and molecular data. Hemimycale oxeata sp. nov. is orange salmon colored in life and has unique oxeote like tornote spicules in addition to the typical (subtylo-)strongyles of the genus. Hemimycale ceadensis sp. nov. is reddish orange in life and has raised, tiny pore sieves, and subtylostrongyles with asymmetrical ends and raphides as microscleres. The diagnosis of the genus Hemimycale was slightly modified for the inclusion of the new species. Maximum-Likelihood analyses of 18S rRNA and COI sequences resulted in the clustering of both new species with the type species of the genus, thus confirming our morphological identification. The value of anatomical characters of pore sieves for diagnosing species and the genus is discussed. A key for species identification is also furnished.


Asunto(s)
Poríferos , Animales , Brasil , ARN Ribosómico 18S
5.
Sci Rep ; 7(1): 17554, 2017 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-29242567

RESUMEN

The cattle tick Rhipicephalus microplus is a hematophagous ectoparasite that causes important economic losses in livestock. Different species of ticks harbor a symbiont bacterium of the genus Coxiella. It was showed that a Coxiella endosymbiont from R. microplus (CERM) is a vertically transmitted mutualist symbiont, comprising 98% of the 16S rRNA sequences in both eggs and larvae. Sequencing of the bacterial genome revealed genes for biosynthetic pathways for several vitamins and key metabolic cofactors that may provide a nutritional complement to the tick host. The CERM was abundant in ovary and Malpighian tubule of fully engorged female. Tetracycline treatment of either the tick or the vertebrate host reduced levels of bacteria in progeny in 74% for eggs and 90% for larvae without major impact neither on the reproductive fitness of the adult female or on embryo development. However, CERM proved to be essential for the tick to reach the adult life stage, as under antibiotic treatment no tick was able to progress beyond the metanymph stage. Data presented here suggest that interference in the symbiotic CERM-R. microplus relationship may be useful to the development of alternative control methods, highlighting the interdependence between ticks and their endosymbionts.


Asunto(s)
Coxiella/fisiología , Rhipicephalus/microbiología , Simbiosis , Animales , Coxiella/efectos de los fármacos , Coxiella/genética , Femenino , Genoma Bacteriano/genética , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Larva/microbiología , Ninfa/efectos de los fármacos , Ninfa/crecimiento & desarrollo , Ninfa/microbiología , Óvulo/efectos de los fármacos , Óvulo/crecimiento & desarrollo , Óvulo/microbiología , Rhipicephalus/crecimiento & desarrollo , Simbiosis/efectos de los fármacos , Tetraciclina/farmacología
6.
Emerg Infect Dis ; 23(10): 1737-1739, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28930027

RESUMEN

We isolated East/Central/South African genotype chikungunya virus during the 2016 epidemic in Rio de Janeiro, Brazil. Genome sequencing revealed unique mutations in the nonstructural protein 4 (NSP4-A481D) and envelope protein 1 (E1-K211T). Moreover, all Brazil East/Central/South isolates shared the exclusive mutations E1-M407L and E2-A103T.


Asunto(s)
Aedes/virología , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/transmisión , Virus Chikungunya/genética , Insectos Vectores/virología , ARN Viral/genética , Adolescente , Adulto , África/epidemiología , Animales , Brasil/epidemiología , Fiebre Chikungunya/virología , Virus Chikungunya/clasificación , Virus Chikungunya/aislamiento & purificación , Chlorocebus aethiops , Femenino , Genotipo , Humanos , Masculino , Filogenia , Células Vero
8.
Diagn Microbiol Infect Dis ; 88(1): 93-94, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28237176

RESUMEN

In this study, we report the isolation of OXA-72-producing Acinetobacter pittii in Brazil. A carbapenem-resistant A. pittii strain was recovered from a hospitalized female patient from Espírito Santo, Southeastern Brazil. PCR screening and DNA sequencing allowed us to identify the presence of blaOXA-72. We observed blaOXA-72 in a ~11kb plasmid and flanked by XerC/XerD-binding sites.


Asunto(s)
Acinetobacter/efectos de los fármacos , Acinetobacter/enzimología , Proteínas Bacterianas/genética , Carbapenémicos/farmacología , Resistencia betalactámica , beta-Lactamasas/genética , Infecciones por Acinetobacter/microbiología , Brasil , ADN Bacteriano/química , ADN Bacteriano/genética , Femenino , Hospitalización , Humanos , Persona de Mediana Edad , Plásmidos/análisis , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
9.
Mem Inst Oswaldo Cruz ; 112(1): 79-80, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28076471

RESUMEN

Alarmingly, the isolation of methicillin-resistant Staphylococcus aureus (MRSA) has been increasing among patients with cystic fibrosis (CF). During a previous molecular characterisation of MRSA isolates obtained from patients with CF from Rio de Janeiro, Brazil, one isolate was identified as the ST398 clone, a livestock-associated (LA) MRSA. In this study, we report the draft genome sequence of an LA-MRSA ST398 clone isolated from a patient with CF.


Asunto(s)
Fibrosis Quística/microbiología , ADN Bacteriano , Genoma Bacteriano , Staphylococcus aureus Resistente a Meticilina/genética , Infecciones Estafilocócicas/microbiología , Femenino , Humanos
10.
Mem. Inst. Oswaldo Cruz ; 112(1): 79-80, Jan. 2017.
Artículo en Inglés | LILACS | ID: biblio-841753

RESUMEN

Alarmingly, the isolation of methicillin-resistant Staphylococcus aureus (MRSA) has been increasing among patients with cystic fibrosis (CF). During a previous molecular characterisation of MRSA isolates obtained from patients with CF from Rio de Janeiro, Brazil, one isolate was identified as the ST398 clone, a livestock-associated (LA) MRSA. In this study, we report the draft genome sequence of an LA-MRSA ST398 clone isolated from a patient with CF.


Asunto(s)
Humanos , Infecciones Estafilocócicas/microbiología , Fibrosis Quística/microbiología , Staphylococcus aureus Resistente a Meticilina/genética , ADN Bacteriano , Genoma Bacteriano
11.
Appl Microbiol Biotechnol ; 101(1): 301-319, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27699477

RESUMEN

The giant snail Achatina fulica is considered an invasive species in most territories in which it was introduced, due to its ability to process a large amount of lignocellulose as a consequence of the presence of a cellulolytic-associated microflora. Streptomyces are well known as crucial agents in the decomposition of complex polymers in soil environments and also as cellulolytic symbionts commonly associated with herbivore insects. Here, we employed a combination of genomic and biochemical tools for a detailed evaluation of the cellulolytic potential of Streptomyces sp. I1.2, an aerobic bacterium isolated from the intestinal lumen of A. fulica in a screening for cellulolytic bacteria. Genomic analysis revealed that the ratio and diversity of CAZy domains and GH families coded by Streptomyces sp. I1.2 are comparable to those present in other highly cellulolytic bacteria. After growth on crystalline cellulose or sugarcane bagasse as sole carbon sources, the functionality of several genes encoding endoglucanases, cellobiohydrolases, xylanases, CBMs, and one ß-glucosidase were confirmed by the combination of enzymatic activity measurements, zymography, TLC, and cellulose-binding assays. The endoglucanases secreted by this isolate were stable at 50 °C and exhibited activity over a broad pH range between 4.0 and 8.0. The endoglucanases and cellobiohydrolases secreted by Streptomyces sp. I1.2 exhibited specific activities that were similar to the levels present in a commercial cellulase preparation from Trichoderma reesei, while I1.2 xylanase levels were even 350 % higher. The results presented here show that Streptomyces sp. I1.2 is promising for future biotechnological applications, since it is able to produce endoglucanases, cellobiohydrolases, and xylanases in appreciable amounts when grown on a low-cost residue such as sugarcane bagasse.


Asunto(s)
Celulosa/metabolismo , Glicósido Hidrolasas/análisis , Streptomyces/enzimología , Streptomyces/metabolismo , Animales , Carbono/metabolismo , Gastrópodos/microbiología , Concentración de Iones de Hidrógeno , Hidrólisis , Streptomyces/genética , Streptomyces/aislamiento & purificación , Temperatura
12.
Genome Announc ; 4(6)2016 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-27932646

RESUMEN

Acinetobacter spp. are found in 53% of air colonization samples from the hospital environment. In this work, we sequenced all the genome of airborne Acinetobacter sp. strain 5-2Ac02. We found important features at the genomic level in regards to the rhizome. By phylogenetic analysis, A. towneri was the species most closely related to Acinetobacter sp. 5-2Ac02.

13.
Mem. Inst. Oswaldo Cruz ; 111(12): 777-780, Dec. 2016. tab
Artículo en Inglés | LILACS | ID: biblio-829254

RESUMEN

Achromobacter species are being increasingly isolated from the respiratory tract of cystic fibrosis patients. Recent reports indicate that Achromobacter ruhlandii is a potential human pathogen in cystic fibrosis-related infections. Here we report the draft genome of four A. ruhlandii strains isolated from cystic fibrosis patients in Brazil. This report describes A. ruhlandii as a potential opportunistic pathogen in cystic fibrosis and provides a framework to for additional enquires into potential virulence factors and resistance mechanisms within this species.


Asunto(s)
Humanos , Achromobacter/genética , Fibrosis Quística/microbiología , ADN Bacteriano/genética , Genoma Bacteriano/genética , Infecciones por Bacterias Gramnegativas/microbiología , Achromobacter/aislamiento & purificación , Secuencia de Bases , Tipificación de Secuencias Multilocus
14.
Mem Inst Oswaldo Cruz ; 111(12): 777-780, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27812598

RESUMEN

Achromobacter species are being increasingly isolated from the respiratory tract of cystic fibrosis patients. Recent reports indicate that Achromobacter ruhlandii is a potential human pathogen in cystic fibrosis-related infections. Here we report the draft genome of four A. ruhlandii strains isolated from cystic fibrosis patients in Brazil. This report describes A. ruhlandii as a potential opportunistic pathogen in cystic fibrosis and provides a framework to for additional enquires into potential virulence factors and resistance mechanisms within this species.


Asunto(s)
Achromobacter/genética , Fibrosis Quística/microbiología , ADN Bacteriano/genética , Genoma Bacteriano/genética , Infecciones por Bacterias Gramnegativas/microbiología , Achromobacter/aislamiento & purificación , Secuencia de Bases , Humanos , Tipificación de Secuencias Multilocus
15.
Mem Inst Oswaldo Cruz ; 111(9): 592-3, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27653362

RESUMEN

Acinetobacter pittii has emerged as an important hospital pathogen that is associated with outbreaks and drug resistance. In cystic fibrosis (CF) patients, the detection of Acinetobacter spp. is rare; however, we isolated the A. pittii sequence type ST643 in several Brazilian CF patients treated in the same centre. The current study describes the draft genome of A. pittii ST643.


Asunto(s)
Infecciones por Acinetobacter/microbiología , Acinetobacter/genética , Fibrosis Quística/microbiología , Acinetobacter/clasificación , ADN Bacteriano/genética , Genoma Bacteriano , Humanos , Tipificación de Secuencias Multilocus , Reacción en Cadena de la Polimerasa
16.
Mem. Inst. Oswaldo Cruz ; 111(9): 592-593, Sept. 2016.
Artículo en Inglés | LILACS | ID: lil-794730

RESUMEN

Acinetobacter pittii has emerged as an important hospital pathogen that is associated with outbreaks and drug resistance. In cystic fibrosis (CF) patients, the detection of Acinetobacter spp. is rare; however, we isolated the A. pittii sequence type ST643 in several Brazilian CF patients treated in the same centre. The current study describes the draft genome of A. pittii ST643.


Asunto(s)
Humanos , Infecciones por Acinetobacter/microbiología , Acinetobacter/genética , Fibrosis Quística/microbiología , Acinetobacter/clasificación , ADN Bacteriano/genética , Genoma Bacteriano , Tipificación de Secuencias Multilocus , Reacción en Cadena de la Polimerasa
17.
J Clin Microbiol ; 53(12): 3894-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26400790

RESUMEN

Molecular methodologies were used to identify 28 Achromobacter spp. from patients with cystic fibrosis (CF). Multilocus sequence typing (MLST) identified 17 Achromobacter xylosoxidans isolates (all bla(OXA-114) positive), nine Achromobacter ruhlandii isolates (all bla(OXA-114) positive), one Achromobacter dolens isolate, and one Achromobacter insuavis isolate. All less common species were misidentified as A. xylosoxidans by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Chronic colonization by clonally related A. ruhlandii isolates was demonstrated.


Asunto(s)
Achromobacter/clasificación , Achromobacter/genética , Fibrosis Quística/complicaciones , Infecciones por Bacterias Gramnegativas/microbiología , Tipificación de Secuencias Multilocus/métodos , Reacción en Cadena de la Polimerasa/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Achromobacter/aislamiento & purificación , Humanos , beta-Lactamasas/genética
18.
J Biotechnol ; 212: 69-70, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26299206

RESUMEN

Haloferax gibbonsii strain ARA6 is a haloarchaea isolated from saline saltern samples from Vermelha lake, located in Araruama region, Rio de Janeiro, Brazil. Its genome displays 66,2% G+C content and is composed by one circular chromosome of 2,945,391 bp and four circular plasmids comprising 993,063 bp. This genomic information shows H. gibbonsii's potential for biotechnological applications and can also contribute to assign evolutionary traits in the genus Haloferax.


Asunto(s)
Genoma Bacteriano , Haloferax/genética , Secuencia de Bases , Brasil , ADN Bacteriano/genética , Haloferax/aislamiento & purificación , Haloferax/metabolismo , Datos de Secuencia Molecular , Péptidos/genética , Polihidroxialcanoatos/metabolismo
19.
Zootaxa ; 3925(4): 536-50, 2015 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-25781759

RESUMEN

In this paper we describe two species of the cosmopolitan sponge genus Haliclona from Rio de Janeiro State, SE Brazil, one of which is new to science and the other a new record to Brazil. Haliclona (Rhizoniera) fugidia sp. nov. is brownish-pink, salmon or cream, thickly encrusting, without oscular tubes and tangential ectosomal reticulation. Choanosomal skeleton is a mostly unispicular ladder-like reticulation of oxeas, very organized near the sponge surface and denser and more disorganized in the interior of the sponge. Haliclona (Halichoclona) vansoesti de Weerdt et al., 1999 was originally described from the Caribbean. It has a very loose connection between ectosome and choanosome, a whitish translucent ectosome combined with a purplish choanosome, a cavernous structure and a friable or crispy consistency. The conspecificity of SE Brazilian and Caribbean populations of H. (Halich.) vansoesti was verified through phylogenetic analysis of small subunit 18S rRNA (18S) and mitochondrial cytochrome oxidase subunit I (COI) gene sequences. A maximum likelihood phylogenetic tree constructed with 18S sequences indicates that specimens of H. (Halich.) vansoesti from Rio de Janeiro were phylogenetically closer to the same species from the Caribbean than to other species of Haliclona. Although not available for H. (Halich.) vansoesti from the Caribbean, COI sequences of our specimens were also quite distinct from those of other Haliclona species. Molecular identification based on DNA sequences is a useful complement to traditional morphology-based taxonomy, especially in highly plastic sponges such as Haliclona spp. and other haplosclerids.


Asunto(s)
Haliclona/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Brasil , Haliclona/anatomía & histología , Haliclona/genética , Haliclona/crecimiento & desarrollo , Tamaño de los Órganos , Filogenia
20.
PLoS One ; 9(8): e104100, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25093512

RESUMEN

BACKGROUND: Multidrug resistance is a critical factor in tuberculosis control. To gain better understanding of multidrug resistant tuberculosis in Brazil, a retrospective study was performed to compare genotypic diversity and drug resistance associated mutations in Mycobacterium tuberculosis isolates from a national reference center. METHODS AND FINDINGS: Ninety-nine multidrug resistant isolates from 12 Brazilian states were studied. Drug-resistance patterns were determined and the rpoB and katG genes were screened for mutations. Genotypic diversity was investigated by IS6110-RFLP and Luminex 47 spoligotyping. Mutations in rpoB and katG were seen in 91% and 93% of the isolates, respectively. Codon 315 katG mutations occurred in 82.8% of the isolates with a predominance of the Ser315Thr substitution. Twenty-five isolates were clustered in 11 groups with identical IS6110-RFLP patterns while 74 showed unique patterns with no association between mutation frequencies or susceptibility profiles. The most prevalent spoligotyping lineages were LAM (47%), T (17%) and Haarlen (12%). The Haarlen lineage showed a higher frequency of codon 516 rpoB mutations while codon 531 mutations prevailed in the other isolates. CONCLUSIONS: Our data suggest that there were no major multidrug resistant M. tuberculosis strains transmitted among patients referred to the reference center, indicating an independent acquisition of resistance. In addition, drug resistance associated mutation profiles were well established among the main spoligotyping lineages found in these Brazilian multidrug resistant isolates, providing useful data for patient management and treatment.


Asunto(s)
Proteínas Bacterianas/genética , Catalasa/genética , Farmacorresistencia Bacteriana Múltiple/genética , Mutación/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis Resistente a Múltiples Medicamentos/genética , Adulto , Técnicas de Tipificación Bacteriana , Brasil/epidemiología , Análisis por Conglomerados , ARN Polimerasas Dirigidas por ADN , Demografía , Femenino , Humanos , Incidencia , Masculino , Mycobacterium tuberculosis/clasificación , Filogenia , Polimorfismo de Longitud del Fragmento de Restricción , Estudios Retrospectivos , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología
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