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1.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37921436

RESUMO

During an ongoing female urinary microbiome research study, strains c17Ua_112T and c31Ua_26T isolated from urine samples of a patient diagnosed with overactive bladder and a healthy postmenopausal woman, respectively, could not be allocated to any Gardnerella species with valid names. In this work, we aimed to characterize these strains. The 16S rRNA gene sequences confirmed that these strains are members of the genus Gardnerella. Phylogenetic analysis based on cpn60 strongly supported two clades, one encompassing c17Ua_112T and nine other strains from the public database, and the other including c31Ua_26T and three other strains, which were distinct from currently recognized species of the genus Gardnerella. Likewise, the phylogenomic tree also showed that strains c17Ua_112T and c31Ua_26T formed independent and robust clusters. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between c17Ua_112T and c31Ua_26T were 79.27 and 27.4 %, respectively. Strain c17Ua_112T showed the highest ANI (94.8 %) and dDDH values (59.8 %) with Gardnerella piotii UGent 18.01T, and strain c31Ua_26T revealed highest ANI (84.2 %) and dDDH (29.1 %) values with Gardnerella swidsinskii GS 9838-1T. Based on the data presented here, the two strains c17Ua_112T and c31Ua_26T represent two novel species of the genus Gardnerella, for which the names Gardnerella pickettii (c17Ua_112T=DSM 113414T=CCP 71T) and Gardnerella greenwoodii (c31Ua_26T=DSM 113415T=CCP 72T) are proposed.


Assuntos
Ácidos Graxos , Microbiota , Feminino , Humanos , Gardnerella/genética , Ácidos Graxos/química , Análise de Sequência de DNA , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Genômica , Hibridização de Ácido Nucleico
2.
J Antimicrob Chemother ; 76(2): 305-311, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33150386

RESUMO

BACKGROUND: In Portugal, carbapenem-resistant Acinetobacter baumannii (CRAB) has been associated with ST98, ST103 and ST208 (Oxford Scheme, Oxf) and a clone has usually been associated with a particular period of time. These clonal shifts were primarily explained by an increased antimicrobial resistance profile. Here we explore genomic and biochemical differences among these and more recent clones, which could further explain the diversity and evolution of this species. METHODS: A total of 116 CRAB isolates (2010-15), together with representatives of a previously described CRAB collection (4 isolates, 2001-06) were characterized by attenuated total reflection Fourier transform infrared spectroscopy (FTIR-ATR) and MLST. Representatives of different FTIR-ATR/MLST clusters were selected for WGS (n = 13), which allowed the in silico extraction of resistance and virulence genes, capsule locus and SNP analysis. RESULTS: A. baumannii clonal shifts of OXA-58-producing ST103Oxf (2001-04), OXA-40-producing ST98Oxf (2002-06), OXA-23-producing ST208Oxf (2006-10) and OXA-23-producing ST218Oxf (2010-15) were accompanied by an increase in AMR genes and virulence factors. FTIR-ATR clustering was congruent with sugar composition predicted from the capsular locus: a fucosamine cluster comprising ST98Oxf, ST103Oxf and a single ST218Oxf isolate; a pseudaminic acid cluster of ST208Oxf and ST1557Oxf isolates; and legionaminic acid, resembling the sialic acid from mammalian cells, in a cluster comprising ST218Oxf isolates. The whole-genome phylogenetic tree was congruent with MLST, with isolates presenting 5-28 938 SNPs. ST208Oxf and ST218Oxf presented ∼1900 SNPs while ST103Oxf and ST1557Oxf showed a greater number of SNPs (∼28 000). CONCLUSIONS: Clonal shifts of CRAB were promoted, in our country, by consecutive virulence and AMR gene pool enlargement, together with features increasing pathogen-host adaptation. Worldwide dominance of ST218Oxf is supported by the combination of high AMR and virulence levels.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Células Clonais , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Portugal , Açúcares , Virulência , beta-Lactamases/genética
3.
BMC Microbiol ; 21(1): 64, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632119

RESUMO

BACKGROUND: To date, information on healthy female urinary microbiota is available mostly at genus level and at one time point. However, profound species-level characterization of healthy urinary microbiome and its stability over time are essential for further correct interpretation of its role in healthy urogenital tract. In this study, we investigated female urogenital microbiome (FUM) at two timepoints (within 2.5-year interval) in young asymptomatic European women. We used culturomics with accurate isolates' identification (MALDI-TOF MS and gene markers sequencing) to understand species stability within healthy FUM. RESULTS: Extended culturomics of voided midstream urine sample pairs revealed a mean Shannon diversity index of 1.25 and mean of 19 species/sample (range 5-39 species; total of 115 species; 1830 isolates). High overall species variability between individuals was captured by beta diversity and a variety of community structure types, with the largest cluster characterized by Lactobacillus crispatus, often in combination with Gardnerella vaginalis or Gardnerella genomospecies 3. Significant FUM composition differences, related to Finegoldia magna and Streptococcus anginosus, according to smoking status were found. A high species variability within individuals (Shannon index SD > 0.5 in 7 out of 10 sample pairs) with a mean of 29% of shared species (range 9.1-41.7%) was observed. Moreover, 4 out of 10 sample pairs clustered in the same community structure type. The stable FUM sample pairs presented high abundance of Lactobacillus crispatus, Streptococcus agalactiae or Lactobacillus paragasseri and Bifidobacterium spp.. Moreover, Gardnerella vaginalis, Gardnerella genomospecies 3 or Gardnerella swidsinskii were often maintained within individuals in high abundance. CONCLUSIONS: Shift in species composition at two distant timepoints was frequently observed among urogenital microbiome of European asymptomatic women. This suggests possible interchange of particular species in healthy FUM and the existence of multiple health-associated FUM compositions in certain individuals. Additionally, we provided additional evidence on resilience of particular bacterial communities and identified certain species more prone to persist in urogenital tract. This study revealed important details on the FUM composition complexity relevant for studies aiming to understand microbiota role in the urogenital tract health and for identification of eubiotic and dysbiotic FUM.


Assuntos
Bactérias/genética , Portador Sadio/microbiologia , Portador Sadio/urina , Microbiota/genética , Vagina/microbiologia , Adulto , Bactérias/classificação , Bactérias/metabolismo , Fenômenos Fisiológicos Bacterianos , Disbiose , Europa (Continente) , Feminino , Humanos , Microbiota/fisiologia , RNA Ribossômico 16S/genética , Fatores de Tempo
4.
Int J Syst Evol Microbiol ; 70(6): 3953-3954, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32515725

RESUMO

During a recent study on members of the genus Lactobacillus we realized that cultures of Lactobacillus fornicalis TV 1018T (=DSM 13171T=ATCC 700934T) are no longer available from the online catalogue of the German Collection of Microorganisms and Cell Cultures GmbH, being displayed as Lactobacillus plantarum at the American Type Culture Collection. Based on data currently available, the organism deposited as ATCC 700934T is a member of the species Lactobacillus plantarum subs. plantarum. Therefore, the type strain of Lactobacillus fornicalis cannot be included in any further scientific comparative study. This matter is referred to the Judicial Commission, asking for an opinion on the status of the species.


Assuntos
Lactobacillus plantarum/classificação , Lactobacillus/classificação , Filogenia
5.
Drug Resist Updat ; 44: 100640, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31492517

RESUMO

Antibiotics are powerful drugs used in the treatment of bacterial infections. The inappropriate use of these medicines has driven the dissemination of antibiotic resistance (AR) in most bacteria. Pseudomonas aeruginosa is an opportunistic pathogen commonly involved in environmental- and difficult-to-treat hospital-acquired infections. This species is frequently resistant to several antibiotics, being in the "critical" category of the WHO's priority pathogens list for research and development of new antibiotics. In addition to a remarkable intrinsic resistance to several antibiotics, P. aeruginosa can acquire resistance through chromosomal mutations and acquisition of AR genes. P. aeruginosa has one of the largest bacterial genomes and possesses a significant assortment of genes acquired by horizontal gene transfer (HGT), which are frequently localized within integrons and mobile genetic elements (MGEs), such as transposons, insertion sequences, genomic islands, phages, plasmids and integrative and conjugative elements (ICEs). This genomic diversity results in a non-clonal population structure, punctuated by specific clones that are associated with significant morbidity and mortality worldwide, the so-called high-risk clones. Acquisition of MGEs produces a fitness cost in the host, that can be eased over time by compensatory mutations during MGE-host coevolution. Even though plasmids and ICEs are important drivers of AR, the underlying evolutionary traits that promote this dissemination are poorly understood. In this review, we provide a comprehensive description of the main strategies involved in AR in P. aeruginosa and the leading drivers of HGT in this species. The most recently developed genomic tools that allowed a better understanding of the features contributing for the success of P. aeruginosa are discussed.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Genoma Bacteriano , Infecções Oportunistas/tratamento farmacológico , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/genética , Células Clonais , Transferência Genética Horizontal , Aptidão Genética , Ilhas Genômicas , Interações Hospedeiro-Patógeno/genética , Humanos , Sequências Repetitivas Dispersas , Epidemiologia Molecular , Infecções Oportunistas/epidemiologia , Infecções Oportunistas/microbiologia , Plasmídeos/química , Plasmídeos/metabolismo , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/patogenicidade , beta-Lactamases/genética , beta-Lactamases/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-33646933

RESUMO

Two Gram-stain-positive strains, c9Ua_26_MT and c11Ua_112_MT, were isolated from voided urine samples from two healthy women. Comparative 16S rRNA gene sequences demonstrated that these novel strains were members of the genus Limosilactobacillus. Phylogenetic analysis based on pheS gene sequences and core genomes showed that each strain formed a separated branch and are closest to Limosilactobacillus vaginalis DSM 5837T. The average nucleotide identity (ANI) and Genome-to-Genome Distance Calculator (GGDC) values between c9Ua_26_MT and the closest relative DSM 5837T were 90.7 and 42.9 %, respectively. The ANI and GGDC values between c11Ua_112_MT and the closest relative DSM 5837T were 91.2 and 45.0 %, and those among the strains were 92.9% and 51,0 %, respectively. The major fatty acids were C12 : 0 (40.2 %), C16 : 0 (26.7 %) and C18 : 1 ω9c (17.7 %) for strain c9Ua_26_MT, and C18 : 1 ω9c (38.0 %), C16 : 0 (33.3 %) and C12 : 0 (17.6 %) for strain c11Ua_112_MT. The genomic DNA G+C content of strains c9Ua_26_MT and c11Ua_112_MT was 39.9 and 39.7 mol%, respectively. On the basis of the data presented here, strains c9Ua_26_MT and c11Ua_112_MT represent two novel species of the genus Limosilactobacillus, for which the names Limosilactobacillus urinaemulieris sp. nov. (c9Ua_26_MT=CECT 30144T=LMG 31899T) and Limosilactobacillus portuensis sp. nov. (c11Ua_112_MT=CECT 30145T=LMG 31898T) are proposed.

7.
J Antimicrob Chemother ; 73(1): 77-83, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29029083

RESUMO

OBJECTIVES: In Pseudomonas aeruginosa, the blaGES-6 carbapenemase gene was previously associated with an In1076 class I integron. Here, we conducted a genome-based analysis and explored the genetic platform associated with the mobility of this gene. METHODS: WGS of a blaGES-6-harbouring P. aeruginosa isolate (FFUP_PS_690) was performed with Illumina HiSeq, de novo assembly was performed using SPAdes and subsequent bioinformatic analysis was performed concerning antibiotic resistance genes, virulence features and mobile genetic elements. RESULTS: The FFUP_PS_690 isolate belongs to the ST235 high-risk clone and houses a novel integrative conjugative element (ICE), hereby named ICEPae690. This clc-like ICE comprises the blaGES-6-harbouring In1076 integron and specific modules. An ExoU island A variant was also identified. CONCLUSIONS: The presence of a 'hitch-hiking' blaGES-6-harbouring In1076 integron in an ICE and an exoU-carrying genomic island highlight the potential spread of these elements through conjugation and/or clonal expansion of the ST235 lineage.


Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/genética , Sequências Repetitivas Dispersas/genética , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , beta-Lactamases/genética , Genoma Bacteriano/genética , Humanos , Testes de Sensibilidade Microbiana , Polimorfismo de Nucleotídeo Único/genética , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação
8.
J Antimicrob Chemother ; 73(1): 52-56, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29069366

RESUMO

OBJECTIVES: Two carbapenemase-carrying plasmids, pLS488 (blaOXA-23) and pLS535 (blaOXA-58) from Acinetobacter pittii clinical isolates, were characterized in this study, including their ability to be transferred to Acinetobacter baumannii. METHODS: The clinical isolates were obtained from drainage fluid of a patient with biliary tract cancer and from an exudate of a patient with a hip infection (Portuguese University Hospital, 2012). Isolate characterization included antimicrobial susceptibility tests, carbapenemase production by Blue-Carba, carbapenem-hydrolysing class D ß-lactamase (CHDL) gene search by PCR sequencing, ApaI-PFGE, CHDL genetic location and plasmid size by hybridization and WGS. Plasmid transfer was performed by conjugation or electroporation. RESULTS: pLS488 constitutes the first conjugative plasmid reported to carry a carbapenem resistance gene in A. pittii and is part of a potential new incompatibility group that might also account for the dissemination of OXA-23 in A. baumannii. pLS535 belongs to the Acinetobacter GR7 incompatibility group and presents a new scaffold for OXA-58. This plasmid lacked the machinery for conjugation, but was transferable by electroporation to A. baumannii. Both isolates, which displayed the same PFGE pattern, represent the first report of CHDL-carrying A. pittii in Portuguese hospitals. CONCLUSIONS: Altogether, these results emphasize the importance of A. pittii, or particular A. pittii clones, as a source of resistance genes, facilitating their dissemination among different bacterial species.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Carbapenêmicos/uso terapêutico , Plasmídeos/genética , beta-Lactamases/genética , Acinetobacter/efeitos dos fármacos , Acinetobacter/genética , Acinetobacter/isolamento & purificação , Infecções por Acinetobacter/microbiologia , Sequência de Bases , Transferência Genética Horizontal/genética , Humanos , Testes de Sensibilidade Microbiana , Portugal , Análise de Sequência de DNA
9.
J Antimicrob Chemother ; 73(4): 873-882, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29373674

RESUMO

Objectives: Information on clonal lineages and genetic platforms involved in the mobilization of carbapenemases between Pseudomonas aeruginosa strains in Portugal is scarce. Here, we outline the genetic drivers contributing to the occurrence of blaVIM-2-producing P. aeruginosa over two decades. Methods: A collection of carbapenem-resistant P. aeruginosa clinical isolates (n = 263, 1995-2014) was screened for carbapenemase production by Blue-Carba and PCR. Antimicrobial susceptibility testing was performed according to EUCAST and clonal analysis by MLST. Nine isolates representing different integrons and STs were selected for WGS, followed by bioinformatics. Results: Twenty-seven blaVIM-2-producing P. aeruginosa belonging to 10 STs were identified, with ST179 and ST111 being the most prevalent and persistent clones. blaVIM-2 was associated with seven class I integrons frequently co-harbouring aminoglycoside resistance genes. In58 was commonly identified, followed by derivatives and In100. blaVIM-2-harbouring transposons of the Tn3 and Tn402 families were linked to different plasmids or integrative conjugative elements of the clc family. Conclusions: The dissemination of blaVIM-2 carrying integrons is associated with a complex interplay between different mobile genetic elements, including the overlooked integrative conjugative elements, and successful spread of particular clones.


Assuntos
Genótipo , Sequências Repetitivas Dispersas , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/enzimologia , beta-Lactamases/metabolismo , Variação Genética , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Portugal/epidemiologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Sequenciamento Completo do Genoma
10.
Adv Exp Med Biol ; 1057: 73-83, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28639245

RESUMO

OBJECTIVE: Biofilm formation has been associated with the persistence of Acinetobacter baumannii in hospital settings and its propensity to cause infection. We investigated the adhesion ability and clonality of 128 A. baumannii isolates recovered from urine and urinary catheters of patients admitted to 5 European hospitals during 1991-2013. METHODS: Isolates identification was confirmed by rpoB sequencing and by the presence of blaOXA-51. The presence of carbapenemases was detected by PCR. Clonality was determined by Sequence Group (SG) identification, Pulsed field gel electrophoresis (PFGE) and Multilocus sequence typing. Adhesion ability was defined by quantitative biofilm production assay and biofilms were characterized by Confocal Laser Microscopy and Scanning Electron Microscopy. RESULTS: The 128 isolates, either resistant (85.9%) or susceptible (14.1%) to carbapenems, and belonging to 50 different PFGE types and 24 different STs, were distributed among SG1 (67.2%), SG2 (10.2%) and other allelic profiles (22.7%). ST218 was the most frequent ST, corresponding to 54,5% of the isolates collected between 2011 and 2013. Among the 109 isolates showing resistance to at least 1 carbapenem, 55% revealed the presence of an acquired carbapenem-hydrolyzing class D - lactamases (CHDL): blaOXA-23 were the most frequent gene detected from 2008 onwards (75%). Among all the clinical isolates, 42.2% were strong biofilm producers, with the older isolates having the highest adhesion ability. Most isolates recovered later, belonging to ST218 and harbouring blaOXA-23, were homogeneously less adhesive. CONCLUSIONS: An evolution towards a decrease in adhesion ability and a CHDL content change was observed along the years in several European countries.


Assuntos
Infecções por Acinetobacter/urina , Acinetobacter baumannii/crescimento & desenvolvimento , Biofilmes , Cateteres Urinários/microbiologia , Acinetobacter baumannii/classificação , Antibacterianos , Proteínas de Bactérias , Eletroforese em Gel de Campo Pulsado , Europa (Continente) , Hospitais , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , beta-Lactamases
11.
Artigo em Inglês | MEDLINE | ID: mdl-28193652

RESUMO

The blaVIM-2-carrying In58 integron has been linked to a chromosomal location in different bacterial species, including Pseudomonas aeruginosa This work reports the first fully sequenced In58-harboring plasmid, which is significantly different from the two previously identified blaVIM-2-carrying plasmids in P. aeruginosablaVIM-2 might have been acquired by transposition of Tn6352, a novel transposon composed of the In58 and ISPa17 elements. The recognition of similar inverted repeat (IR) sites by ISPa17 reveals a common mobilization process associated with acquisition of the blaVIM-2 and blaVIM-1 genes.


Assuntos
Proteínas de Bactérias/genética , Elementos de DNA Transponíveis/genética , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , beta-Lactamases/genética , Sequência de Bases , DNA Bacteriano/genética , Humanos , Integrons/genética , Sequências Repetidas Invertidas/genética , Tipagem de Sequências Multilocus , Plasmídeos/genética , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
J Antimicrob Chemother ; 72(8): 2225-2229, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28505370

RESUMO

Objectives: In Pseudomonas aeruginosa , bla VIM-2 has been mostly associated with a chromosomal location and rarely with a plasmid backbone. Until now, only three complete bla VIM-2 -carrying plasmid sequences have been described in this species. Here we explore the modular structure of pJB37, the first bla VIM-2 -carrying megaplasmid described in P. aeruginosa . Methods: The complete nucleotide sequence of plasmid pJB37 was determined with an Illumina HiSeq, with de novo assembly by SPAdes, annotation by RAST and searching for antimicrobial resistance genes and virulence factors. Conjugation assays were conducted. Results: Megaplasmid pJB37 (464 804 bp long and GC content of 57.2%) comprised: an IncP-2 repA-oriV-parAB region; a conjugative transfer region ( traF , traG , virD2 and trbBCDEJLFGI genes); Tn 6356 , a new putative bla VIM-2 -carrying transposon; heavy metal (mercury and tellurite) resistance operons; and an arsenal of virulence genes. Plasmid pJB37 was transferable by conjugation to a spontaneous rifampicin-resistant mutant of P. aeruginosa PAO1. Here, a bla VIM-2 -harbouring In58 integron was associated with a new complex transposable structure, herein named Tn 6356 , suggesting that In58 was most likely acquired by insertion of this element. Conclusions: The mosaic arrangement exhibited by the pJB37 IncP-2 megaplasmid, which highlights the vast assembly potential of distinct genetic elements in a Pseudomonas widespread plasmid platform, gives new insights into bacterial adaptation and evolution.


Assuntos
Elementos de DNA Transponíveis , Plasmídeos , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/genética , beta-Lactamases/genética , Conjugação Genética , Transferência Genética Horizontal , Humanos , Infecções por Pseudomonas/microbiologia , Análise de Sequência de DNA
13.
J Antimicrob Chemother ; 70(4): 1016-20, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25630639

RESUMO

OBJECTIVES: The present study was designed to provide a snapshot on carbapenemase-producing Pseudomonas aeruginosa (n=11) and Acinetobacter baumannii (n=7) isolates in hospitalized patients (November 2011, January-March 2012) from two main hospitals in Bucharest, south Romania. METHODS: Clonality among isolates was established by PFGE, MLST and Fourier transform infrared spectroscopy. Carbapenemases were screened by the Blue-Carba test, PCR and sequencing. Transferability of blaOXA-23 was tested by conjugation and plasmid typing (number, size and identity) was assessed by S1-PFGE, replicon typing, hybridization and PCR mapping. RESULTS: All P. aeruginosa isolates carried chromosomally located blaVIM-2, associated with a common class 1 integron (aacA7-blaVIM-2) or an atypical configuration (aacA7-blaVIM-2-dfrB5-tniC). These isolates belonged to unusual lineages; mostly ST233 disseminated in one hospital unit, with ST364 and ST1074 also being detected. A. baumannii isolates carried blaOXA-23 in Tn2008, which was found truncating a TnaphA6 transposon located in a common 60 kb GR6 (aci6) pABKp1-like conjugative plasmid in highly related CC92 clones (ST437, ST764 and ST765), where CC stands for clonal complex. CONCLUSIONS: Our results show the spread of VIM-2-producing P. aeruginosa and OXA-23-producing A. baumannii clinical isolates in two hospitals from Bucharest and highlight a peculiar population structure in this Eastern European country. Also, we demonstrate the dissemination of a common and conjugative aci6 pABKp1-like plasmid scaffold in different A. baumannii clones and we report the first known identification of Tnaph6-carrying pACICU2-like plasmids in Europe.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/enzimologia , Proteínas de Bactérias/metabolismo , Infecção Hospitalar/microbiologia , Genótipo , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/enzimologia , beta-Lactamases/metabolismo , Acinetobacter baumannii/classificação , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Proteínas de Bactérias/genética , Conjugação Genética , Eletroforese em Gel de Campo Pulsado , Transferência Genética Horizontal , Hospitais , Humanos , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Plasmídeos/análise , Plasmídeos/classificação , Reação em Cadeia da Polimerase , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Romênia , Espectroscopia de Infravermelho com Transformada de Fourier , beta-Lactamases/genética
14.
Int J Med Microbiol ; 304(5-6): 669-77, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24877727

RESUMO

MALDI-TOF MS is becoming the technique of choice for rapid bacterial identification at species level in routine diagnostics. However, some drawbacks concerning the identification of closely related species such as those belonging to the Acinetobacter calcoaceticus-Acinetobacter baumannii (Acb) complex lead to high rates of misidentifications. In this work we successfully developed an approach that combines MALDI-TOF MS and chemometric tools to discriminate the six Acb complex species (A. baumannii, Acinetobacter nosocomialis, Acinetobacter pittii, A. calcoaceticus, genomic species "Close to 13TU" and genomic species "Between 1 and 3"). Mass spectra of 83 taxonomically well characterized clinical strains, reflecting the breadth of currently known phenetic diversity within the Acb complex, were achieved from intact cells and cell extracts and analyzed with hierarchical cluster analysis (HCA) and partial least squares discriminant analysis (PLSDA). This combined approach lead to 100% of correct species identification using mass spectra obtained from intact cells. Moreover, it was possible to discriminate two Acb complex species (genomic species "Close to 13TU" and genomic species "Between 1 and 3") not included in the MALDI Biotyper database.


Assuntos
Infecções por Acinetobacter/diagnóstico , Acinetobacter baumannii/química , Acinetobacter baumannii/classificação , Acinetobacter calcoaceticus/química , Acinetobacter calcoaceticus/classificação , Técnicas Bacteriológicas/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Infecções por Acinetobacter/microbiologia , Humanos
15.
Biotechnol Rep (Amst) ; 42: e00839, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38633817

RESUMO

A bacterium, Acinetobacter soli ANG344B, isolated from river water, exhibited an exceptional capacity to produce 2-phenylethanol (2-PE) using L-phenylalanine (L-Phe) as a precursor-a capability typically observed in yeasts rather than bacteria. Bioreactor experiments were conducted to evaluate the production performance, using glucose as the carbon source for cellular growth and L-Phe as the precursor for 2-PE production. Remarkably, A. soli ANG344B achieved a 2-PE concentration of 2.35 ± 0.26 g/L in just 24.5 h of cultivation, exhibiting a global volumetric productivity of 0.10 ± 0.01 g/L.h and a production yield of 0.51 ± 0.01 g2-PE/gL-Phe, a result hitherto reported only for yeasts. These findings position A. soli ANG344B as a highly promising microorganism for 2-PE production. Whole-genome sequencing of A. soli strain ANG344 revealed a genome size of 3.52 Mb with a GC content of 42.7 %. Utilizing the Rapid Annotation using Subsystem Technology (RAST) server, 3418 coding genes were predicted, including genes coding for enzymes previously associated with the metabolic pathway of 2-PE production in other microorganisms, yet unreported in Acinetobacter species. Through gene mapping, 299 subsystems were identified, exhibiting 30 % subsystem coverage. The whole genome sequence data was submitted to NCBI GeneBank with the BioProject ID PRJNA982713. These draft genome data offer significant potential for exploiting the biotechnological capabilities of A. soli strain ANG344 and for conducting further comparative genomic studies.

16.
Biosensors (Basel) ; 13(2)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36831915

RESUMO

The development of rapid, reliable, and low-cost methods that enable discrimination among clinically relevant bacteria is crucial, with emphasis on those listed as WHO Global Priority 1 Critical Pathogens, such as carbapenem-resistant Acinetobacter baumannii and carbapenem-resistant or ESBL-producing Klebsiella pneumoniae. To address this problem, we developed and validated a protocol of surface-enhanced Raman spectroscopy (SERS) with silver nanostars for the discrimination of A. baumannii and K. pneumoniae species, and their globally disseminated and clinically relevant antibiotic resistant clones. Isolates were characterized by mixing bacterial colonies with silver nanostars, followed by deposition on filter paper for SERS spectrum acquisition. Spectral data were processed with unsupervised and supervised multivariate data analysis methods, including principal component analysis (PCA) and partial least-squares discriminant analysis (PLSDA), respectively. Our proposed SERS procedure using silver nanostars adsorbed to the bacteria, followed by multivariate data analysis, enabled differentiation between and within species. This pilot study demonstrates the potential of SERS for the rapid discrimination of clinically relevant A. baumannii and K. pneumoniae species and clones, displaying several advantages such as the ease of silver nanostars synthesis and the possible use of a handheld spectrometer, which makes this approach ideal for point-of-care applications.


Assuntos
Acinetobacter baumannii , Klebsiella pneumoniae , Prata/química , Projetos Piloto , Análise Espectral Raman/métodos , Carbapenêmicos , Bactérias , Células Clonais
17.
Antimicrob Agents Chemother ; 56(7): 3969-72, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22526316

RESUMO

The spread of OXA-24/OXA-40 (OXA-24/40)-producing Acinetobacter spp. in the Iberian Peninsula has been strongly influenced by clonal expansion, but the role of horizontal gene transfer has scarcely been explored. bla(OXA-24/40)-carrying plasmids and genetic environments were characterized in representative (n = 15) Acinetobacter species clinical isolates (obtained between 2001 and 2007) by Acinetobacter baumannii PCR-based replicon typing, sequencing, hybridization, and restriction fragment length polymorphism. Besides the identification of bla(OXA-24/40) within the chromosomes of some isolates, the circulation of common bla(OXA-24/40)-carrying plasmids (30-kb repA_AB; 10-kb aci2) and genetic backbones among Acinetobacter spp. was demonstrated.


Assuntos
Acinetobacter/enzimologia , Acinetobacter/genética , Plasmídeos/genética , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/genética , Transferência Genética Horizontal/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , beta-Lactamases/genética
19.
Microbiol Spectr ; 10(6): e0130822, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36383025

RESUMO

The knowledge of bacterial species diversity within the female urinary microbiome (FUM) is essential for understanding the role of the FUM in urinary tract health and disease. This study aimed to characterize the bacterial species diversity of the FUM of asymptomatic reproductive-age European women by combining extended culturomics and long-read sequencing of the near-full-length 16S rRNA gene. A total of 297 bacterial species (median of 53 species/sample) were identified, yet only 22% of the species were detected by both culture and sequencing methods. Recently recognized Gardnerella, Lactobacillus, and Limosilactobacillus species and 5 new putative Corynebacterium species were identified by culturomics, while anaerobic species (e.g., 11 Peptoniphilus spp.) were mostly detected by amplicon sequencing. Notably, there was not a single species common to all samples, although members of the genus Lactobacillus were detected in all. Lactobacillus crispatus, Lactobacillus iners, and Lactobacillus mulieris were observed in high relative abundance in several samples, as well as other species (e.g., Streptococcus agalactiae, Fannyhessea vaginae, Gardnerella vaginalis, Gardnerella swidsinskii), while low-abundance members (e.g., Finegoldia magna) were often more prevalent. A moderate correlation (Mantel test; r = 0.5) between community structure types captured by culturomics and amplicon sequencing was observed, highlighting the benefit of combining both methodologies. This study provided a detailed FUM structure at the species level, which is critical to unveil the potential relationship between specific microbiome members and urinary diseases/disorders. Moreover, the different capacity to characterize microbiome profiles of culturomic and amplicon sequencing is described, providing valuable insights for further urinary microbiome studies. IMPORTANCE The bacterial species diversity within the female urinary microbiome (FUM) has been insufficiently characterized. This study demonstrated that complementarity between optimized culture-dependent and -independent approaches is highly beneficial for comprehensive FUM species profiling by detecting higher FUM species diversity than previously reported, including identification of unreported species belonging to the genera Lactobacillus, Limosilactobacillus, and Latilactobacillus and putative novel Corynebacterium species. Although some species were present in high relative abundance, low-abundance members were more prevalent. FUM classification into community structure types demonstrated high interindividual differences in urinary microbiome composition among asymptomatic women. We also report moderate correlation between culture-dependent and -independent derived data-highlighting drawbacks of each methodological approach. Our findings suggest that FUM bacterial diversity reported from previous studies may be underestimated. Finally, our results contribute to the fundamental knowledge of the FUM required for further exploration of the urinary microbiome role in urinary tract diseases.


Assuntos
Microbiota , Sistema Urinário , Humanos , Feminino , RNA Ribossômico 16S/genética , Sistema Urinário/microbiologia , Gardnerella vaginalis/genética , Bactérias/genética , Corynebacterium/genética , Microbiota/genética , População Europeia , Vagina/microbiologia
20.
J Antimicrob Chemother ; 66(1): 62-5, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21051372

RESUMO

OBJECTIVES: this study focused on the population structure of OXA-23-producing Acinetobacter baumannii clinical isolates from Rio de Janeiro, Brazil. METHODS: the analysis included several genomic typing methods, including PFGE, two multilocus sequence typing (MLST) schemes, sequence group (SG) determination and bla(OXA-51-like) sequencing. The genomic context of the bla(OXA-23) gene was also evaluated using I-CeuI hybridizations and PCR assays. RESULTS: congruent clustering was obtained revealing four lineages. In accordance, four new sequence types (STs) (ST131, ST132, ST133 and ST134) were obtained with the MLST-OD scheme (associated with the Oxford Database) and four (ST79, ST15 and two new allelic profiles) with the MLST-IP scheme (developed by the Institute Pasteur). Four SGs (SG1, SG4 and two new profiles) were identified, allowing the association of 70% of the isolates with European clone II. bla(OXA-51-like) sequencing revealed the presence of bla(OXA-66), bla(OXA-69), bla(OXA-95) and bla(OXA-132). CONCLUSIONS: identification of new STs together with new SG profiles are findings suggestive of a local diversity hotspot that is worth exploring.


Assuntos
Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/classificação , Acinetobacter baumannii/enzimologia , Variação Genética , beta-Lactamases/biossíntese , beta-Lactamases/genética , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Técnicas de Tipagem Bacteriana , Brasil/epidemiologia , Análise por Conglomerados , Eletroforese em Gel de Campo Pulsado , Genótipo , Humanos , Epidemiologia Molecular , Tipagem Molecular , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
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