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1.
Front Med (Lausanne) ; 9: 931379, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35966843

RESUMEN

Chryseobacterium indologenes is a non-glucose-fermenting Gram-negative bacillus. This emerging multidrug resistant opportunistic nosocomial pathogen can cause severe infections in neonates and immunocompromised patients. This study aimed to present the first detailed draft genome sequence of a multidrug-resistant C. indologenes strain isolated from the cerebrospinal fluid of an infant hospitalized at the Neonatal Intensive Care Unit of Brazilian Tertiary Hospital. We first analyzed the susceptibility of C. indologenes strain to different antibiotics using the VITEK 2 system. The strain demonstrated an outstanding resistance to all the antibiotic classes tested, including ß-lactams, aminoglycosides, glycylcycline, and polymyxin. Next, C. indologenes was whole-genome-sequenced, annotated using Prokka and Rapid Annotation using Subsystems Technology (RAST), and screened for orthologous groups (EggNOG), gene ontology (GO), resistance genes, virulence genes, and mobile genetic elements using different software tools. The draft genome contained one circular chromosome of 4,836,765 bp with 37.32% GC content. The genomic features of the chromosome present numerous genes related to cellular processes that are essential to bacteria. The MDR C. indologenes revealed the presence of genes that corresponded to the resistance phenotypes, including genes to ß-lactamases (bla IND-13, bla CIA-3, bla TEM-116, bla OXA-209, bla VEB-15), quinolone (mcbG), tigecycline (tet(X6)), and genes encoding efflux pumps which confer resistance to aminoglycosides (RanA/RanB), and colistin (HlyD/TolC). Amino acid substitutions related to quinolone resistance were observed in GyrA (S83Y) and GyrB (L425I and K473R). A mutation that may play a role in the development of colistin resistance was detected in lpxA (G68D). Chryseobacterium indologenes isolate harbored 19 virulence factors, most of which were involved in infection pathways. We identified 13 Genomic Islands (GIs) and some elements associated with one integrative and conjugative element (ICEs). Other elements linked to mobile genetic elements (MGEs), such as insertion sequence (ISEIsp1), transposon (Tn5393), and integron (In31), were also present in the C. indologenes genome. Although plasmids were not detected, a ColRNAI replicon type and the most resistance genes detected in singletons were identified in unaligned scaffolds. We provided a wide range of information toward the understanding of the genomic diversity of C. indologenes, which can contribute to controlling the evolution and dissemination of this pathogen in healthcare settings.

2.
J Glob Antimicrob Resist ; 20: 36-40, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31279132

RESUMEN

OBJECTIVES: Enterobacter hormaechei is an important causative agent of severe infections in critically ill patients. Aminoglycosides are among the main antibiotics for the treatment of E. hormaechei infections, however the development of antimicrobial resistance is an increasing problem. RmtG is a 16S rRNA methyltransferase, a class of enzymes conferring high-level resistance to clinically relevant aminoglycosides. The aim of this study was to characterise the full genetic context of plasmids harbouring the rmtG gene in two aminoglycoside-resistant E. hormaechei isolated in Brazil. METHODS: ThermtG-harbouring plasmids were transferred to an Escherichia coli J53 recipient strain and were fully sequenced using a MiSeq sequencing system. Complete genome assemblies were accomplished using a combination of Newbler v.3.0, SPAdes 3.10.0 and phrap/cross_match programs. Plasmid sequences were annotated using RAST server and were then manually curated using BLAST databases and ISfinder. Easyfig 2.0 was used to map and compare regions of interest containing rmtG in both plasmids. RESULTS: Both isolates carried thermtG gene on an IncA/C plasmid of ˜152kb and ˜235kb, respectively, associated with a Tn3 transposon. The plasmids contain a transfer region as well as genes involved in plasmid stability and resistance to ß-lactams, sulfonamides and quaternary ammonium compounds. One of the plasmids also carried the mrk operon encoding type 3 fimbriae. CONCLUSION: This first detection ofrmtG in E. hormaechei supports the ability for horizontal transfer. The location in complex genetic platforms carried by Tn3 transposons in IncA/C plasmids may facilitate dissemination to other Gram-negative pathogens, further limiting treatment options.


Asunto(s)
Cromosomas Bacterianos/genética , Enterobacter/aislamiento & purificación , Infecciones por Enterobacteriaceae/diagnóstico , Metiltransferasas/genética , Plásmidos/genética , Infecciones Urinarias/microbiología , Proteínas Bacterianas/genética , Brasil , Enterobacter/clasificación , Enterobacter/genética , Transferencia de Gen Horizontal , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Secuenciación Completa del Genoma
3.
Diagn Microbiol Infect Dis ; 96(2): 114900, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31859023

RESUMEN

This study used whole-genome sequencing (WGS) and PFGE to analysis KPC-2-producing Klebsiella pneumoniae strains from clinical specimens collected in Brazilian hospitals. The study identifies the emergence of a novel small IncX3 plasmid (pKPB11), 12,757-bp in length, in a high-risk K. pneumoniae ST11/CG258 lineage, a successful clonal group in Brazil, carrying the blaKPC-2 gene on a non-Tn4401 genetic element (NTEKPC-Ic). Comparative analysis of the pKPB11 showed that this plasmid reduced its size, losing part of its conjugation apparatus. The pKPB11 was also compared to another strain sequenced in this study (KPC89) that had the hybrid IncX3-IncU plasmid (pKP89), of approximately 45 kb in length, similarly carrying the blaKPC-2 gene on NTEKPC-Ic. To the best of our knowledge, pKPB11 is the first example of small IncX3 plasmid found in a high-risk KPC-2-producing K. pneumoniae ST11/CG258.


Asunto(s)
Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/clasificación , Klebsiella pneumoniae/genética , Plásmidos/genética , beta-Lactamasas/genética , Brasil/epidemiología , Orden Génico , Genoma Bacteriano , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Infecciones por Klebsiella/epidemiología , Tipificación de Secuencias Multilocus
6.
Microb Drug Resist ; 25(8): 1127-1131, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31074706

RESUMEN

The dissemination of antimicrobial resistance genes and the bacterium that harbor them have increasingly become a public concern, especially in low- and middle-income countries. The present study used whole-genome sequencing to analyze 10 KPC-2-producing Klebsiella pneumoniae isolates obtained from clinical specimens originated from Brazilian hospitals. The study documents a relevant "snapshot" of the presence of class 1 integrons in 90% of the strains presenting different gene cassettes (dfrA30, dfrA15, dfrA12, dfrA14, aadA1, aadA2, and aac(6')Iq), associated or not with transposons. Two strains presented nonclassical integron (lacking the normal 3'conserved segment). In general, most strains showed a complex resistome, characterizing them as highly resistant. Integrons, a genetically stable and efficient system, confer to bacteria as highly adaptive and low cost evolution potential to bacteria, even more serious when associated with high-risk clones, indicating an urgent need for control and prevention strategies to avoid the spread of resistance determinants in Brazil. Despite this, although the class 1 integron identified in the KPC-2-producing K. pneumoniae clones is important, our findings suggest that other elements probably have a greater impact on the spread of antimicrobial resistance, since many of these important genes were not related to this cassette.


Asunto(s)
Klebsiella pneumoniae/genética , beta-Lactamasas/genética , Brasil , Elementos Transponibles de ADN/genética , Farmacorresistencia Bacteriana Múltiple/genética , Humanos , Integrones , Secuenciación Completa del Genoma/métodos
7.
Artículo en Inglés | MEDLINE | ID: mdl-30533840

RESUMEN

Penicillium brasilianum (strain LaBioMMi 136) has been reported to be a great producer of secondary metabolites and a source of enzymes of biotechnological interest. Here, we report the draft genome sequence of P. brasilianum (strain LaBioMMi 136), isolated as an endophyte from the plant Melia azedarach (family Meliaceae).

9.
PLoS One ; 13(6): e0198643, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29889876

RESUMEN

The emergence of infections associated to new antimicrobial resistance in Acinetobacter baumannii (Ab) genotypes represents a major challenge. In this context, this study aimed to determine the diversity of resistance mechanisms and investigate clonal dissemination and predominant sequence types (STs) in multidrug-resistant Ab strains of clinical (tracheal aspirate, n = 17) and environmental (surface, n = 6) origins. Additionally, the major clones found in clinical (A) and environmental (H) strains had their complete genomes sequenced. All strains were submitted to polymerase chain reactions (PCR) for the detection of the ISAba1/blaOXA-51-like and ISAba1/blaOXA-23-like genes, while the expression of genes encoding the carO porin, AdeABC (adeB), AdeFGH (adeG), and AdeIJK (adeJ) efflux pumps was determined by real time PCR (qPCR). Most of the strains were characterized as extensively drug-resistant (XDR) with high minimal inhibitory concentrations (MICs) detected for tigecycline and carbapenems. Associations between ISAba1/OXA-51 and ISAba1/OXA-23 were observed in 91.3% and 52.2% of the strains, respectively. Only the adeB gene was considered hyper-expressed. Furthermore, most of the strains analyzed by the MuLtilocus Sequence-Typing (MLST) were found to belong to the clonal complex 113 (CC113). In addition, a new ST, ST1399, belonging to CC229, was also discovered herein. Strains analyzed by whole genome sequencing presented resistance genes linked to multidrug-resistance phenotypes and confirmed the presence of Tn2008, which provides high levels carbapenem-resistance.


Asunto(s)
Acinetobacter baumannii/enzimología , Proteínas Bacterianas/metabolismo , beta-Lactamasas/metabolismo , Acinetobacter baumannii/genética , Secuencia de Aminoácidos , Antibacterianos/farmacología , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/genética , Carbapenémicos/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Porinas/química , Porinas/genética , Alineación de Secuencia , Tigeciclina/farmacología , Secuenciación Completa del Genoma , beta-Lactamasas/genética
10.
J Med Microbiol ; 67(4): 523-528, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29509136

RESUMEN

In this study, we describe the frequency of virulence genes in Klebsiella pneumoniae carbapenemase-2-producing Klebsiella pneumoniae (KPC-KP), including hypervirulent (hv) and hypermucoviscous (hm) strains by whole-genome sequencing. We also evaluate the capacity for biofilm formation by using phenotypic techniques. The occurrence of several virulence genes (fimABCDEFGHIK, mrkABCDFHJ, ecpA, wabG, entB, ugE, irp1, irp2, traT, iutA and ureADE) and a high frequency of hvhmKPC-KP isolates was found. Most hospital-associated lineages of KPC-KP belong to the international clonal group 258 (CG258). Biofilm formation was a constant feature among 90.9 % of KPC-KP strains. This report suggests a close relationship between ST437 and weak biofilm production, given that all weakly biofilm-producing strains belonged to this sequence type. This also supports the dissemination of KPC-KP containing numerous virulence determinants belonging to the biofilm-producing CG258 type in Brazil, including hv and hm strains. These factors allow this pathogen to cause infections, leading to its rapid expansion and persistence in hospital settings.


Asunto(s)
Proteínas Bacterianas/metabolismo , Biopelículas , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/enzimología , Klebsiella pneumoniae/patogenicidad , beta-Lactamasas/metabolismo , Proteínas Bacterianas/genética , Brasil , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/fisiología , Pruebas de Sensibilidad Microbiana , beta-Lactamasas/genética
11.
J Glob Antimicrob Resist ; 13: 35-36, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29476983

RESUMEN

OBJECTIVES: Klebsiella pneumoniae is considered an opportunistic pathogen and an important agent of nosocomial and community infections. It presents the ability to capture and harbour several antimicrobial resistance genes and, in this context, the extensive use of carbapenems to treat serious infections has been responsible for the selection of several resistance genes. This study reports the draft genome sequence of a KPC-2-producing K. pneumoniae strain (Kp10) simultaneously harbouring blaCTX-M-15 and blaCTX-M-59 genes isolated from urine culture of a patient with Parkinson's disease. METHODS: Classical microbiological methods were applied to isolate and identify the strain, and PCR and sequencing were used to identify and characterise the genes and the genetic environment. Whole-genome sequencing (WGS) was performed using a Nextera XT DNA library and a NextSeq platform. RESULTS: WGS analysis revealed the presence of 5915 coding genes, 46 RNA-encoding genes and 255 pseudogenes. Kp10 belonged to sequence type 340 (ST340) of clonal complex 258 (CC258) and carried 20 transferable genes associated with antimicrobial resistance, comprising seven drug classes. Although the simultaneous presence of different blaCTX-M genes in the same strain is rarely reported, the blaKPC-2, blaCTX-M-15 and blaCTX-M-59 genes were not associated with the same genetic mobile structure in Kp10. CONCLUSIONS: These results confirm the capacity of K. pneumoniae to harbour several antimicrobial resistance genes. Thus, this draft genome could help in future epidemiological studies regarding the dissemination of clinically relevant resistance genes.


Asunto(s)
Farmacorresistencia Bacteriana , Genoma Bacteriano , Secuencias Repetitivas Esparcidas , Klebsiella pneumoniae/genética , Análisis de Secuencia de ADN , beta-Lactamasas/genética , Anciano , Técnicas Bacteriológicas , Femenino , Genes Bacterianos , Humanos , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/aislamiento & purificación , Anotación de Secuencia Molecular , Enfermedad de Parkinson/complicaciones , Reacción en Cadena de la Polimerasa , Orina/microbiología , Secuenciación Completa del Genoma
13.
Bioengineering (Basel) ; 4(3)2017 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-28952541

RESUMEN

The use of culture-independent approaches, such as metagenomics, provides complementary access to environmental microbial diversity. Mangrove environments represent a highly complex system with plenty of opportunities for finding singular functions. In this study we performed a functional screening of fosmid libraries obtained from an oil contaminated mangrove site, with the purpose of identifying clones expressing hydrolytic activities. A novel gene coding for a ß-N-acetylhexosaminidase with 355 amino acids and 43KDa was retrieved and characterized. The translated sequence showed only 38% similarity to a ß-N-acetylhexosaminidase gene in the genome of Veillonella sp. CAG:933, suggesting that it might constitute a novel enzyme. The enzyme was expressed, purified, and characterized for its enzymatic activity on carboxymethyl cellulose, p-Nitrophenyl-2acetamide-2deoxy-ß-d-glucopyranoside, p-Nitrophenyl-2acetamide-2deoxy-ß-d-galactopyranoside, and 4-Nitrophenyl ß-d-glucopyranoside, presenting ß-N-acetylglucosaminidase, ß-glucosidase, and ß-1,4-endoglucanase activities. The enzyme showed optimum activity at 30 °C and pH 5.5. The characterization of the putative novel ß-N-acetylglucosaminidase enzyme reflects similarities to characteristics of the environment explored, which differs from milder conditions environments. This work exemplifies the application of cultivation-independent molecular techniques to the mangrove microbiome for obtaining a novel biotechnological product.

14.
Antimicrob Agents Chemother ; 59(12): 7387-95, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26392506

RESUMEN

In Enterobacteriaceae, the blaNDM genes have been found in many different genetic contexts, and a wide diversity of plasmid scaffolds bearing those genes has been found. In August 2013, we identified NDM-1-producing Escherichia coli and Enterobacter hormaechei strains from a single rectal swab sample from a patient hospitalized in Rio de Janeiro, Brazil, who had no history of travel abroad. Complete DNA sequencing using the Illumina platform and annotation of the two plasmids harboring the blaNDM-1 gene, one from each strain, showed that they belonged to incompatibility groups IncFIIK and IncX3 and harbored a novel transposon named Tn3000. Similar genetic structures have been identified among other isolates in Brazil but also on plasmids from other continents. Our findings suggest that the blaNDM-1 gene may be transmitted by Tn3000 in different parts of the world.


Asunto(s)
Elementos Transponibles de ADN/genética , Enterobacter/aislamiento & purificación , Escherichia coli/aislamiento & purificación , beta-Lactamasas/metabolismo , Antibacterianos/farmacología , Aztreonam/farmacología , Proteínas Bacterianas/genética , Secuencia de Bases , Brasil , Conjugación Genética , Secuencia Conservada , Enterobacter/efectos de los fármacos , Enterobacter/genética , Enterobacter/metabolismo , Infecciones por Enterobacteriaceae/microbiología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Escherichia coli/metabolismo , Fosfomicina/farmacología , Humanos , India , Pruebas de Sensibilidad Microbiana , Marruecos , Nepal , Plásmidos , Recto/microbiología , beta-Lactamasas/genética
15.
Antimicrob Agents Chemother ; 58(5): 2958-60, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24566176

RESUMEN

We sequenced the oldest blaKPC-2-bearing plasmid isolated in Brazil and another plasmid also carried by a Klebsiella pneumoniae strain of sequence type 442 (ST442), isolated 52 months later. Both plasmids present an IncN backbone and few acquired regions. Because the 2005 plasmid presented deletions and a truncated gene within Tn4401b compared to the 2009 plasmid, we can thus infer that IncN blaKPC-2-bearing plasmids pFCF1305 and pFCF3SP had a common ancestor circulating in Brazil prior to May 2005.


Asunto(s)
Klebsiella pneumoniae/enzimología , Klebsiella pneumoniae/genética , Plásmidos/genética , Brasil , Farmacorresistencia Bacteriana Múltiple/genética , beta-Lactamasas/genética
16.
J Bacteriol ; 194(23): 6620-1, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23144380

RESUMEN

The bacterium Corynebacterium pseudotuberculosis is of major veterinary importance because it affects livestock, particularly sheep, goats, and horses, in several countries, including Australia, Brazil, the United States, and Canada, resulting in significant economic losses. In the present study, we describe the complete genome of the Corynebacterium pseudotuberculosis Cp316 strain, biovar equi, isolated from the abscess of a North American horse.


Asunto(s)
Corynebacterium pseudotuberculosis/genética , ADN Bacteriano/química , ADN Bacteriano/genética , Genoma Bacteriano , Análisis de Secuencia de ADN , Absceso/microbiología , Absceso/veterinaria , Animales , California , Infecciones por Corynebacterium/microbiología , Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/aislamiento & purificación , Enfermedades de los Caballos/microbiología , Caballos , Datos de Secuencia Molecular
17.
Front Genet ; 3: 38, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22461785

RESUMEN

Improvements in genome sequencing techniques have resulted in generation of huge volumes of data. As a consequence of this progress, the genome assembly stage demands even more computational power, since the incoming sequence files contain large amounts of data. To speed up the process, it is often necessary to distribute the workload among a group of machines. However, this requires hardware and software solutions specially configured for this purpose. Grid computing try to simplify this process of aggregate resources, but do not always offer the best performance possible due to heterogeneity and decentralized management of its resources. Thus, it is necessary to develop software that takes into account these peculiarities. In order to achieve this purpose, we developed an algorithm aimed to optimize the functionality of de novo assembly software ABySS in order to optimize its operation in grids. We run ABySS with and without the algorithm we developed in the grid simulator SimGrid. Tests showed that our algorithm is viable, flexible, and scalable even on a heterogeneous environment, which improved the genome assembly time in computational grids without changing its quality.

18.
Stand Genomic Sci ; 7(2): 189-99, 2012 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-23408795

RESUMEN

The Actinobacteria, Corynebacterium pseudotuberculosis strain P54B96, a nonmotile, non-sporulating and a mesophile bacterium, was isolated from liver, lung and mediastinal lymph node lesions in an antelope from South Africa. This strain is interesting in the sense that it has been found together with non-tuberculous mycobacteria (NTMs) which could nevertheless play a role in the lesion formation. In this work, we describe a set of features of C. pseudotuberculosis P54B96, together with the details of the complete genome sequence and annotation. The genome comprises of 2.34 Mbp long, single circular genome with 2,084 protein-coding genes, 12 rRNA, 49 tRNA and 62 pseudogenes and a G+C content of 52.19%. The analysis of the genome sequence provides means to better understanding the molecular and genetic basis of virulence of this bacterium, enabling a detailed investigation of its pathogenesis.

19.
J Bacteriol ; 193(24): 7025-6, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22123771

RESUMEN

In this work, we report the whole-genome sequence of Corynebacterium pseudotuberculosis bv. equi strain CIP 52.97 (Collection Institut Pasteur), isolated in 1952 from a case of ulcerative lymphangitis in a Kenyan horse, which has evidently caused significant losses to agribusiness. Therefore, obtaining this genome will allow the detection of important targets for postgenomic studies, with the aim of minimizing problems caused by this microorganism.


Asunto(s)
Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/genética , Genoma Bacteriano , Enfermedades de los Caballos/microbiología , Animales , Secuencia de Bases , Infecciones por Corynebacterium/microbiología , Corynebacterium pseudotuberculosis/aislamiento & purificación , Caballos , Kenia , Datos de Secuencia Molecular
20.
J Bacteriol ; 193(22): 6420-1, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22038974

RESUMEN

In this work, we report the complete genome sequence of a Corynebacterium pseudotuberculosis PAT10 isolate, collected from a lung abscess in an Argentine sheep in Patagonia, whose pathogen also required an investigation of its pathogenesis. Thus, the analysis of the genome sequence offers a means to better understanding of the molecular and genetic basis of virulence of this bacterium.


Asunto(s)
Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/genética , Genoma Bacteriano , Absceso Pulmonar/microbiología , Enfermedades de las Ovejas/microbiología , Animales , Argentina , Secuencia de Bases , Corynebacterium pseudotuberculosis/aislamiento & purificación , Corynebacterium pseudotuberculosis/patogenicidad , Datos de Secuencia Molecular , Ovinos , Virulencia
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