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1.
Int J Syst Evol Microbiol ; 73(10)2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37889259

RESUMEN

In 1989, Bouvet and Jeanjean delineated five proteolytic genomic species (GS) of Acinetobacter, each with two to four human isolates. Three were later validly named, whereas the remaining two (GS15 and GS16) have been awaiting nomenclatural clarification. Here we present the results of the genus-wide taxonomic study of 13 human strains classified as GS16 (n=10) or GS15 (n=3). Based on core genome phylogenetic analysis, the strains formed two respective but closely related phylogroups within the Acinetobacter haemolytic clade. The intraspecies genomic average nucleotide identity based on blast (ANIb) values for GS16 and GS15 reached ≥94.9 % and ≥98.7, respectively, whereas ANIb values between them were 92.5-93.5% and those between them and the known species were ≤91.5 %. GS16 and GS15 could be differentiated from the other Acinetobacter species by their ability to lyse gelatin and sheep blood and to assimilate d,l-lactate, along with their inability to acidify d-glucose and assimilate glutarate. In contrast, GS16 and GS15 were indistinguishable from one another by metabolic/physiological features or whole-cell MALDI-TOF mass spectra. All the GS15/GS16 genomes contained genes encoding a class D ß-lactamase, Acinetobacter-derived cephalosporinase and aminoglycoside 6'-N-acetyltransferase. Searching NCBI databases revealed genome sequences of three additional isolates of GS16, but none of GS15. We conclude that our data support GS16 as representing a novel species, but leave the question of the taxonomic status of GS15 open, given its close relatedness to GS16 and the small number of available strains. We propose the name Acinetobacter higginsii sp. nov. for GS16, with the type strain NIPH 1872T (CCM 9243T=CIP 70.18T=ATCC 17988T).


Asunto(s)
Acinetobacter , Humanos , Animales , Ovinos , Análisis de Secuencia de ADN , Filogenia , Ácidos Grasos/química , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , ARN Ribosómico 16S/genética , Composición de Base , Genómica , Hibridación de Ácido Nucleico
5.
Folia Microbiol (Praha) ; 67(1): 121-127, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34590203

RESUMEN

The isolation of Planococcus glaciei (designed strain CNCTC 7660) from blood of a patient with appendicitis is reported. Species P. glaciei (type strain CGMCC 1.6846 T) was for the first time identified as an environmental bacterium acquired from a glacier in China in 2009. To reveal the identity of the isolate CNCTC 7660, the 16S rDNA sequencing and the whole genome sequencing (Illumina MiSeq, Oxford Nanopore) were performed. The level of 16S rDNA gene sequencing similarity between CNCTC 7660 and CGMCC 1.6846 T was 99.55%. Phylogenetic analysis and average nucleotide analysis (ANI) based on the whole genome sequencing confirmed that the isolate CNCTC 7660 and CGMCC1.6846 T had ANI value above the taxonomic threshold for belonging to the same species (95%). The G + C content of CNCTC 7660 DNA was 46.8% (mol/mol). Except for the growth temperature, strains CGMCC1.6846 T and CNCTC 7660 were distinguished also biochemically. Due to the lack of information about the pathogenicity of P. glaciei, the possibility that it exerts pathogenicity in persons is suggested. But for understanding the nature of this species, further cases are needed.


Asunto(s)
Ácidos Grasos , Técnicas de Tipificación Bacteriana , República Checa , ADN Bacteriano/genética , Ácidos Grasos/análisis , Humanos , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
7.
Syst Appl Microbiol ; 44(4): 126217, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34107439

RESUMEN

This study aimed to define the taxonomic position and structure of a novel, taxonomically unique group of 26 Acinetobacter strains, provisionally designated Taxon 24 (T24). The strains were recovered from soil and freshwater ecosystems (n = 21) or animals (n = 5) in Czechia, Scotland, Germany, the Netherlands and Turkey between 1993 and 2015. They were non-glucose-acidifying, nonhemolytic, nonproteolytic, growing at 32 °C and on acetate and ethanol as single carbon sources, but not on 4-hydroxybenzoate and mostly not at 37 °C. Their whole-genome sequences were 3.0-3.7 Mb in size, with GC contents of 39.8-41.3%. Based on core genome phylogenetic analysis, the 26 strains formed a distinct clade within the genus Acinetobacter, with strongly supported subclades termed T24A (n = 11), T24B (n = 8), T24C (n = 2), T24D (n = 3) and T24E (n = 2). The internal genomic ANIb values for these subclades were >94.8%, while the ANIb values between them were <92.5%. The results of MALDI-TOF MS-based analyses agreed with this classification. The five subclades differed from each other in the results of one to six carbon source assimilation tests. Given the genomic and phenotypic distinctness, internal coherence, numbers of available strains and geographically diverse origin of T24A and T24B, we propose the names Acinetobacter terrae sp. nov. and Acinetobacter terrestris sp. nov. for these two taxa, respectively. The type strains are ANC 4282v (= CCM 8986T = CCUG 73811T = CNCTC 8082T) and ANC 4471T (= CCM 8985T = CCUG 73812T = CNCTC 8093T), respectively. We conclude that these two species together with the other T24 strains represent a widely dispersed Acinetobacter clade primarily associated with terrestrial ecosystems.


Asunto(s)
Acinetobacter , Filogenia , Acinetobacter/clasificación , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , República Checa , ADN Bacteriano/genética , Ecosistema , Agua Dulce/microbiología , Genes Bacterianos , Alemania , Países Bajos , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Escocia , Análisis de Secuencia de ADN , Microbiología del Suelo , Turquía
8.
BMC Microbiol ; 20(1): 224, 2020 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-32711478

RESUMEN

BACKGROUND: The resistance of Streptococcus pneumoniae to macrolides is becoming an increasingly important issue and thus it is important to understand the genetics related to adaptation of this species to the widespread use of antibiotics in Europe. The 58 isolates of S. pneumoniae belonging to sequence type (ST) 416 and serotype 19A and to several different phenotypes originated from Italy, Portugal and Czech Republic were thus sequenced on Illumina MiSeq. The aim of the study was to describe genetical origine of isolates, investigate their macrolide resistance and suggest reasons for spread of ST416 in the Czech Republic. RESULTS: Investigation of genes associated with serotype determined serotype switch between 15B and 19A serotypes and core genome multilocus sequence typing (cgMLST) confirmed the origine of concerned isolates in Netherlands15B-37 clone. Inspected genomes proved variability of genes associated with the macrolide resistance even within closely genetically relative isolates. CONCLUSIONS: Participation of 19A/ST416 on the spread of Netherlands15B-37 is accompanied by serotype switch between 19A and 15B serotypes and with acquisition of genes involved in macrolide resistance to the clone that was originally macrolide susceptible. There is evident tendency to interchanging and modifications of these and surrounding genes, that could lead to accelerate spreading of this sequence type in regions with high macrolide consumption.


Asunto(s)
Farmacorresistencia Bacteriana , Macrólidos/farmacología , Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/clasificación , Secuenciación Completa del Genoma/métodos , República Checa , Genoma Bacteriano , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Italia , Tipificación de Secuencias Multilocus , Países Bajos , Filogenia , Filogeografía , Polimorfismo de Nucleótido Simple , Portugal , Serogrupo , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/aislamiento & purificación
9.
Syst Appl Microbiol ; 42(2): 159-167, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30392743

RESUMEN

In 1986, Bouvet and Grimont delineated two related taxa of the genus Acinetobacter termed genospecies (GS) 8 and 9. They proposed the name Acinetobacter lwoffii for GS8, which included the supposed type strain (CIP 64.10). As the authenticity of CIP 64.10 was later questioned, this study aimed at reassessing the taxonomy of these genospecies. We investigated 52 strains of GS8 or GS9, including CIP 64.10 and the genuine type strain of A. lwoffii (NCTC 5866T). All strains were subjected to the genus-wide comparative analyses of MALDI-TOF whole-cell mass spectra, rpoB gene sequences and metabolic traits while whole-genome sequences were analysed for 16 strains. The strains were classified into two distinct groups corresponding to GS8 (n=15) and GS9 (n=37). CIP 64.10 fell within GS8 whereas NCTC 5866T belonged to GS9. Intraspecies ANIb values for the genomes of GS8 (n=6) and GS9 (n=10) were ≥96.1% and ≥95.4%, respectively, whereas the ANIb values between them were 86.8-88.6%. Based on core genome phylogeny, GS8 and GS9 formed a distinct clade within the genus, with two respective, strongly supported subclades. GS8 and GS9 were similar in physiological and catabolic properties but were separable by MALDI-TOF MS. We conclude that the name A. lwoffii pertains to GS9 and not to GS8 as originally assumed and that these groups represent two species. We propose the name Acinetobacter pseudolwoffii sp. nov. for GS8, with ANC 5044T (=CCM 8638T=CCUG 67963T=CIP 111642T) as the type strain, and provide the emended description of A. lwoffii.


Asunto(s)
Acinetobacter/clasificación , Filogenia , Técnicas de Tipificación Bacteriana , ARN Polimerasas Dirigidas por ADN/genética , Genes Bacterianos , Secuenciación Completa del Genoma
10.
J Med Microbiol ; 67(7): 1003-1011, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29856703

RESUMEN

Purpose. The aim of this study was to characterize serogroup 19 isolates resistant to macrolides and/or penicillin found among pneumococci recovered from cases of invasive and respiratory tract disease in the Czech Republic in 2014.Methods. Pneumococcal isolates of serotypes 19A (n=26) and 19F (n=10) that were non-susceptible to penicillin and/or macrolides and had been collected in 2014 were analysed using multi-locus sequence typing (MLST). Four isolates representing the major clones were subjected to whole-genome sequencing (WGS).Results. The penicillin-susceptible macrolide-resistant isolates of serotype 19A were mainly associated with sequence type (ST) 416 belonging to clonal complex (CC) 199, and the penicillin-resistant isolates were of serotype 19F belonging to ST1464 (CC 320). WGS revealed the presence of pilus 1, in association with pilus 2, in serotype19F isolates belonging to CC 320. Another adhesin, pneumococcal serine-rich protein (PsrP), was only present in serotype 19A isolates of ST416. Analysis of the penicillin-binding proteins (PBPs) of serotype 19F penicillin-resistant isolates (ST1464 and ST271) performed on PBP1a, 2b and 2x identified a large number of mutations in comparison to the reference strain, R6. Both isolates contained a unique PBP profile; however, they were highly similar to PBP sequences of the Taiwan19F-14 reference strain. The Pbp2b sequences of both 19F isolates showed the lowest similarity to those of the Taiwan19F-14 strain (91 % similarity), while they were also found to be distantly related to each other (94 % similarity).Conclusions. WGS revealed specific virulence factors in antibiotic-resistant pneumococcal clones that spread rapidly in the post-vaccine era in the Czech Republic.


Asunto(s)
Tipificación Molecular , Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/microbiología , Vacunas Neumococicas/inmunología , Serogrupo , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/aislamiento & purificación , Adulto , Anciano , Antibacterianos/farmacología , Niño , Preescolar , República Checa , Farmacorresistencia Bacteriana , Femenino , Genes Bacterianos , Genotipo , Humanos , Lactante , Masculino , Persona de Mediana Edad , Fenotipo , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/administración & dosificación , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/genética , Secuenciación Completa del Genoma , Adulto Joven
12.
Artículo en Inglés | MEDLINE | ID: mdl-28993328

RESUMEN

The objective of this study was to perform molecular surveillance for assessing the spread of carbapenemase-producing Pseudomonas aeruginosa in Czech hospitals. One hundred thirty-six carbapenemase-producing isolates were recovered from 22 hospitals located throughout the country. Sequence type 357 (ST357) dominated (n = 120) among carbapenemase producers. One hundred seventeen isolates produced IMP-type (IMP-7 [n = 116] and IMP-1 [n = 1]) metallo-ß-lactamases (MßLs), 15 produced the VIM-2 MßL, and the remaining isolates expressed the GES-5 enzyme. The blaIMP-like genes were located in three main integron types, with In-p110-like being the most prevalent (n = 115). The two other IMP-encoding integrons (In1392 and In1393) have not been described previously. blaVIM-2-carrying integrons included In59-like, In56, and a novel element (In1391). blaGES-5 was carried by In717. Sequencing data showed that In-p110-like was associated with a Tn4380-like transposon inserted in genomic island LESGI-3 in the P. aeruginosa chromosome. The other integrons were also integrated into the P. aeruginosa chromosome. These findings indicated the clonal spread of ST357 P. aeruginosa, carrying the IMP-7-encoding integron In-p110, in Czech hospitals. Additionally, the sporadic emergence of P. aeruginosa producing different carbapenemase types, associated with divergent or novel integrons, punctuated the ongoing evolution of these bacteria.


Asunto(s)
Cromosomas Bacterianos/química , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Pseudomonas/epidemiología , Pseudomonas aeruginosa/genética , beta-Lactamasas/genética , Antibacterianos/farmacología , Carbapenémicos/farmacología , República Checa/epidemiología , Monitoreo Epidemiológico , Expresión Génica , Islas Genómicas , Genotipo , Hospitales , Humanos , Incidencia , Integrones , Isoenzimas/genética , Isoenzimas/metabolismo , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/enzimología , Pseudomonas aeruginosa/aislamiento & purificación , beta-Lactamasas/metabolismo
13.
Folia Microbiol (Praha) ; 60(1): 53-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25113540

RESUMEN

Strains of genus Citrobacter (152 isolates from 1950 to 1988 deposited in the Czech National Collection of Type Cultures, Prague) were re-classified using biological and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) methods. One-hundred thirty-six strains (ca. 90 %) were identified to the species level using the biological method with evaluation by Farmer matrix. MALDI-TOF MS exhibited better identification capability, the data being more compact; the method was unambiguously successful in typing 145 (95 %) strains. Comparison of the results of identification by the two methods revealed differences (for 12 samples) in identified species which, considering all biochemical and/or MS characteristics, could be attributed to the natural variability of strains and close relation of the misidentified species (all of them belonged to the Citrobacter freundii complex). Taking into account all the above data, both methods can be considered reliable; however, the MALDI-TOF MS exhibits higher accuracy, efficiency, and rapidity.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Bioquímica/métodos , Citrobacter/química , Citrobacter/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Citrobacter/clasificación , Citrobacter/genética
14.
Microb Drug Resist ; 21(1): 74-84, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25188031

RESUMEN

A total of 2,683 nonrepetitive Escherichia coli isolates were collected from microbiological laboratories covering all regions of the Czech Republic, during April 2011. Antimicrobial susceptibility patterns of E. coli were assessed. All 38 cefotaxime-resistant (CTX-R) isolates were found to be extended-spectrum ß-lactamase (ESBL)-positive by the double-disc synergy test. Thirty-two of those isolates produced enzymes of CTX-M-1 family, five of CTX-M-9 family, and one isolate both CTX-M types. Genotyping by multilocus sequence typing classified all ESBL-producing isolates into 13 sequence types (STs). ST131 was the most prevalent and was exclusively correlated with E. coli belonging to the more-virulent phylogroup B2. blaCTX-M-15 and blaCTX-M-9-like genes were mainly carried by plasmids belonging to the IncF group, while replicon I1 was predominant among CTX-M-1-encoding plasmids. Additionally, 63% of the ESBL-producing isolates were also resistant to ciprofloxacin. Sequence analysis of quinolone resistance-determining regions of gyrA and parC revealed the presence of amino acid substitutions in 22 out of 23 ciprofloxacin-resistant isolates. The acc(6')-Ib-cr and qnrB1 plasmid-mediated quinolone resistance genes were also detected in some of the isolates. This is the first report on the emergence and spread of CTX-M-producing E. coli in the community of the Czech Republic, indicating the high prevalence of ST131 clone among CTX-M producers.


Asunto(s)
Infecciones Comunitarias Adquiridas/microbiología , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Escherichia coli/aislamiento & purificación , beta-Lactamasas/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Niño , Preescolar , Células Clonales , Infecciones Comunitarias Adquiridas/epidemiología , Conjugación Genética , República Checa/epidemiología , ADN Bacteriano/genética , Pruebas Antimicrobianas de Difusión por Disco , Electroforesis en Gel de Campo Pulsado , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Escherichia coli/genética , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/epidemiología , Femenino , Fluoroquinolonas/farmacología , Genes Bacterianos , Humanos , Lactante , Masculino , Persona de Mediana Edad , Tipificación de Secuencias Multilocus , Filogenia , Plásmidos/genética , Prevalencia , Virulencia/genética
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