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1.
Ann Clin Microbiol Antimicrob ; 23(1): 54, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886694

RESUMO

BACKGROUND: Achromobacter spp. are opportunistic pathogens, mostly infecting immunocompromised patients and patients with cystic fibrosis (CF) and considered as difficult-to-treat pathogens due to both intrinsic resistance and the possibility of acquired antimicrobial resistance. Species identification remains challenging leading to imprecise descriptions of resistance in each taxon. Cefiderocol is a broad-spectrum siderophore cephalosporin increasingly used in the management of Achromobacter infections for which susceptibility data remain scarce. We aimed to describe the susceptibility to cefiderocol of a collection of Achromobacter strains encompassing different species and isolation sources from CF or non-CF (NCF) patients. METHODS: We studied 230 Achromobacter strains (67 from CF, 163 from NCF patients) identified by nrdA gene-based analysis, with available susceptibility data for piperacillin-tazobactam, meropenem and trimethoprim-sulfamethoxazole. Minimal inhibitory concentrations (MICs) of cefiderocol were determined using the broth microdilution reference method according to EUCAST guidelines. RESULTS: Strains belonged to 15 species. A. xylosoxidans represented the main species (71.3%). MICs ranged from ≤ 0.015 to 16 mg/L with MIC50/90 of ≤ 0.015/0.5 mg/L overall and 0.125/2 mg/L against 27 (11.7%) meropenem-non-susceptible strains. Cefiderocol MICs were not related to CF/NCF origin or species although A. xylosoxidans MICs were statistically lower than those of other species considered as a whole. Considering the EUCAST non-species related breakpoint (2 mg/L), 228 strains (99.1%) were susceptible to cefiderocol. The two cefiderocol-resistant strains (A. xylosoxidans from CF patients) represented 3.7% of meropenem-non-susceptible strains and 12.5% of MDR strains. CONCLUSIONS: Cefiderocol exhibited excellent in vitro activity against a large collection of accurately identified Achromobacter strains, irrespective of species and origin.


Assuntos
Achromobacter , Antibacterianos , Cefiderocol , Cefalosporinas , Fibrose Cística , Infecções por Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana , Humanos , Achromobacter/efeitos dos fármacos , Achromobacter/genética , Achromobacter/isolamento & purificação , Achromobacter/classificação , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Fibrose Cística/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia
2.
Syst Appl Microbiol ; 47(4): 126516, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38772267

RESUMO

The tolerance of ash trees against the pathogen Hymenoscyphus fraxineus seems to be associated with the occurrence of specific microbial taxa on leaves. A group of bacterial isolates, primarily identified on tolerant trees, was investigated with regard to their taxonomic classification and their potential to suppress the ash dieback pathogen. Examination of OGRI values revealed a separate species position. A phylogenomic analysis, based on orthologous and marker genes, indicated a separate genus position along with the species Achromobacter aestuarii. Furthermore, analysis of the ratio of average nucleotide identities and genome alignment fractions demonstrated genomic dissimilarities typically observed for inter-genera comparisons within this family. As a result of these investigations, the strains are considered to represent a separate species within a new genus, for which the name Schauerella fraxinea gen. nov., sp. nov. is proposed, with the type strain B3P038T (=LMG 33092 T = DSM 115926 T). Additionally, a reclassification of the species Achromobacter aestuarii as Schauerella aestuarii comb. nov. is proposed. In a co-cultivation assay, the strains were able to inhibit the growth of a H. fraxineus strain. Accordingly, a functional analysis of the genome of S. fraxinea B3P038T revealed genes mediating the production of antifungal substances. This potential, combined with the prevalent presence in the phyllosphere of tolerant ash trees, makes this group interesting for an inoculation experiment with the aim of controlling the pathogen in an integrative approach. For future field trials, a strain-specific qPCR system was developed to establish an efficient method for monitoring the inoculation success.


Assuntos
DNA Bacteriano , Filogenia , Doenças das Plantas , RNA Ribossômico 16S , DNA Bacteriano/genética , RNA Ribossômico 16S/genética , Doenças das Plantas/microbiologia , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Genoma Bacteriano/genética , Achromobacter/genética , Achromobacter/classificação , Achromobacter/isolamento & purificação , Folhas de Planta/microbiologia , Apiaceae/microbiologia
3.
Microb Genom ; 7(7)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34292148

RESUMO

Achromobacter species are increasingly being detected in cystic fibrosis (CF) patients, where they can establish chronic infections by adapting to the lower airway environment. To better understand the mechanisms contributing to a successful colonization by Achromobacter species, we sequenced the whole genome of 54 isolates from 26 patients with occasional and early/late chronic lung infection. We performed a phylogenetic analysis and compared virulence and resistance genes, genetic variants and mutations, and hypermutability mechanisms between chronic and occasional isolates. We identified five Achromobacter species as well as two non-affiliated genogroups (NGs). Among them were the frequently isolated Achromobacter xylosoxidans and four other species whose clinical importance is not yet clear: Achromobacter insuavis, Achromobacter dolens, Achromobacter insolitus and Achromobacter aegrifaciens. While A. insuavis and A. dolens were isolated only from chronically infected patients and A. aegrifaciens only from occasionally infected patients, the other species were found in both groups. Most of the occasional isolates lacked functional genes involved in invasiveness, chemotaxis, type 3 secretion system and anaerobic growth, whereas the great majority (>60%) of chronic isolates had these genomic features. Interestingly, almost all (n=22/23) late chronic isolates lacked functional genes involved in lipopolysaccharide production. Regarding antibiotic resistance, we observed a species-specific distribution of blaOXA genes, confirming what has been reported in the literature and additionally identifying blaOXA-2 in some A. insolitus isolates and observing no blaOXA genes in A. aegrifaciens or NGs. No significant difference in resistance genes was found between chronic and occasional isolates. The results of the mutator genes analysis showed that no occasional isolate had hypermutator characteristics, while 60% of early chronic (<1 year from first colonization) and 78% of late chronic (>1 year from first colonization) isolates were classified as hypermutators. Although all A. dolens, A. insuavis and NG isolates presented two different mutS genes, these seem to have a complementary rather than compensatory function. In conclusion, our results show that Achromobacter species can exhibit different adaptive mechanisms and some of these mechanisms might be more useful than others in establishing a chronic infection in CF patients, highlighting their importance for the clinical setting and the need for further studies on the less clinically characterized Achromobacter species.


Assuntos
Achromobacter/classificação , Achromobacter/genética , Fibrose Cística/microbiologia , Genoma Bacteriano/genética , Infecções por Bactérias Gram-Negativas/microbiologia , Infecção Persistente/microbiologia , Achromobacter/isolamento & purificação , Farmacorresistência Bacteriana/genética , Humanos , Pulmão/microbiologia , Proteínas MutS/genética , Fatores de Virulência/genética , Sequenciamento Completo do Genoma , beta-Lactamases/genética
4.
Clin Microbiol Infect ; 27(1): 126.e1-126.e5, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32283265

RESUMO

OBJECTIVES: Achromobacter spp. are emerging pathogens in respiratory samples from cystic fibrosis patients. The current reference methods (nrdA-sequencing or multilocus sequence typing) can identify 18 species which are often misidentified by conventional techniques as A. xylosoxidans. A few studies have suggested that matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF/MS) provides accurate identification of the genus but not of species. The aims of this study were (a) to generate a database for MALDI-TOF/MS Bruker including the 18 species, (b) to evaluate the suitability of the database for routine laboratory identification, and (c) to compare its performance with that of the currently available Bruker default database. METHODS: A total of 205 isolates belonging to the 18 species identified by nrdA sequencing were used to build a local database. Main spectra profiles (MSPs) were created according to Bruker's recommendations for each isolate with the Biotyper software. Performance of the default Bruker database and ours for routine use were compared by testing 167 strains (including 38 isolates used from MSP creation) belonging to the 18 species identified by nrdA sequencing directly from colonies cultivated on various media. RESULTS: Our new database accurately identified 99.4% (166/167) of the isolates from the 18 species (score ≥2.0) versus only 50.9% (85/167) with the Bruker database. In the Bruker database 17.3% of the isolates (29/167) were incorrectly identified as another species despite a score of ≥2.0. CONCLUSIONS: The use of MALDI-TOF/MS in combination with a database developed with samples from 18 Achromobacter species provides rapid and accurate identification. This tool could be used to help future clinical studies.


Assuntos
Achromobacter/isolamento & purificação , Bases de Dados Factuais , Infecções por Bactérias Gram-Negativas/diagnóstico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Achromobacter/classificação , Achromobacter/genética , Testes Diagnósticos de Rotina , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Ribonucleosídeo Difosfato Redutase/genética , Software
5.
Microb Genom ; 6(7)2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32667877

RESUMO

Several members of the Gram-negative environmental bacterial genus Achromobacter are associated with serious infections, with Achromobacter xylosoxidans being the most common. Despite their pathogenic potential, little is understood about these intrinsically drug-resistant bacteria and their role in disease, leading to suboptimal diagnosis and management. Here, we performed comparative genomics for 158 Achromobacter spp. genomes to robustly identify species boundaries, reassign several incorrectly speciated taxa and identify genetic sequences specific for the genus Achromobacter and for A. xylosoxidans. Next, we developed a Black Hole Quencher probe-based duplex real-time PCR assay, Ac-Ax, for the rapid and simultaneous detection of Achromobacter spp. and A. xylosoxidans from both purified colonies and polymicrobial clinical specimens. Ac-Ax was tested on 119 isolates identified as Achromobacter spp. using phenotypic or genotypic methods. In comparison to these routine diagnostic methods, the duplex assay showed superior identification of Achromobacter spp. and A. xylosoxidans, with five Achromobacter isolates failing to amplify with Ac-Ax confirmed to be different genera according to 16S rRNA gene sequencing. Ac-Ax quantified both Achromobacter spp. and A. xylosoxidans down to ~110 genome equivalents and detected down to ~12 and ~1 genome equivalent(s), respectively. Extensive in silico analysis, and laboratory testing of 34 non-Achromobacter isolates and 38 adult cystic fibrosis sputa, confirmed duplex assay specificity and sensitivity. We demonstrate that the Ac-Ax duplex assay provides a robust, sensitive and cost-effective method for the simultaneous detection of all Achromobacter spp. and A. xylosoxidans and will facilitate the rapid and accurate diagnosis of this important group of pathogens.


Assuntos
Achromobacter/classificação , Fibrose Cística/microbiologia , Genômica/métodos , Infecções por Bactérias Gram-Negativas/diagnóstico , Achromobacter/genética , Achromobacter/isolamento & purificação , Achromobacter denitrificans/classificação , Achromobacter denitrificans/genética , Achromobacter denitrificans/isolamento & purificação , Diagnóstico Precoce , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Tipagem de Sequências Multilocus , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Escarro
6.
Rev. argent. microbiol ; 52(1): 13-18, mar. 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1155678

RESUMO

Abstract Different phenotype-based techniques and molecular tools were used to describe the distribution of different Achromobacter species in patients with cystic fibrosis (CF) in Argentina, and to evaluate their antibiotic resistance profile. Phenotypic identification was performed by conventional biochemical tests, commercial galleries and MALDI-TOF MS. Genetic approaches included the detection of A. xylosoxidans specific marker blaoxa-114, the amplificaron and sequencing of the 16S rRNA gene, nrdA and blaOXA complete sequence, and MLST analysis. Phenotypic approaches, even MALDI-TOF, rendered inconclusive or misleading results. On the contrary, concordant results were achieved with the nrdA sequencing or sequence type (ST) analysis, and the complete blaOXA sequencing, allowing a reliable discrimination of different Achromobacter species. A. xylosoxidans accounted for 63% of Achromobacter infections and A. ruhlandii accounted for 17%. The remaining species corresponded to A. insuavis, A. dolens, A. marplatensis and A. pulmonis. Antimicrobial susceptibilities were determined by the agar dilution method according to CLSI guidelines. Piperacillin, piperacillin/tazobactam and car-bapenems were the most active antibiotics. However, the emergence of carbapenem-resistant isolates was detected. In conclusion, prompt and accurate identification tools were necessary to determine that different Achromobacter species may colonize/infect the airways of patients with CF. Moreover, antimicrobial therapy should be administered based on the susceptibility profile of individual Achromobacter sp. isolates. © 2019 Asociación Argentina de Microbiología. Published by Elsevier España, S.L.U. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/).


Resumen Se emplearon diversas técnicas fenotípicas y moleculares para describir la distribución de diferentes especies del género Achromobacter en pacientes con fibrosis quística (FQ) en Argentina, y se evaluó el perfil de resistencia a los antibióticos. Se realizó la identificación fenotípica por pruebas bioquímicas convencionales, galerías comerciales y MALDI-TOF MS. El enfoque genético incluyó la detección del marcador especie-específico de A. xylosoxidans bla[PRESERVECIRC]tu, la amplificación y la secuenciación de los genes ARNr 16S, nrdA y secuencia completa de blaOXA, y el análisis por MLST. Los enfoques fenotípicos, incluso la técnica de MALDI-TOF, proporcionaron resultados no concluyentes o erróneos. Por el contrario, se obtuvieron resultados concordantes entre la secuenciación del gen nrdA o el análisis de secuenciotipos (ST) y la secuenciación completa de blaOXA, lo que permitió una discriminación confiable de las diferentes especies de Achromobacter. A. xylosoxidans representó el 63% de las infecciones por Achromobacter y A. ruhlandii representó el 17%. Las especies restantes correspondieron a A. insuavis, A. dolens, A. marplatensis y A. pulmonis. Se determinó la sensibilidad a antimicrobianos por el método de dilución en agar de acuerdo al CLSI. Los antibióticos más activos fueron piperacilina, piperacilina/tazobactam y carbapenemes. Sin embargo, se detectó la emergencia de aislamientos resistentes a carbapenemes. En conclusión, resultaron necesarias herramientas de identificación rápida y precisas para determinar las diferentes especies del género Achro-mobacter capaces de colonizar/infectar las vías respiratorias de los pacientes con FQ. Asimismo, la terapia antimicrobiana debería llevarse a cabo en función del perfil de sensibilidad de los aislamientos individuales de Achromobacter spp. © 2019 Asociacion Argentina de Microbiología. Publicado por Elsevier Espana, S.L.U. Este es un artículo Open Access bajo la licencia CC BY-NC-ND (https://creativecommons.org/licenses/by-nc-nd/4.0/).


Assuntos
Humanos , Fibrose Cística/microbiologia , Achromobacter/isolamento & purificação , Fenótipo , Argentina , Farmacorresistência Bacteriana , Achromobacter/classificação , Achromobacter/efeitos dos fármacos , Achromobacter/genética , Antibacterianos/farmacologia
7.
Rev Argent Microbiol ; 52(1): 13-18, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31253503

RESUMO

Different phenotype-based techniques and molecular tools were used to describe the distribution of different Achromobacter species in patients with cystic fibrosis (CF) in Argentina, and to evaluate their antibiotic resistance profile. Phenotypic identification was performed by conventional biochemical tests, commercial galleries and MALDI-TOF MS. Genetic approaches included the detection of A. xylosoxidans specific marker blaoxa-114, the amplification and sequencing of the 16S rRNA gene, nrdA and blaOXA complete sequence, and MLST analysis. Phenotypic approaches, even MALDI-TOF, rendered inconclusive or misleading results. On the contrary, concordant results were achieved with the nrdA sequencing or sequence type (ST) analysis, and the complete blaOXA sequencing, allowing a reliable discrimination of different Achromobacter species. A. xylosoxidans accounted for 63% of Achromobacter infections and A. ruhlandii accounted for 17%. The remaining species corresponded to A. insuavis, A. dolens, A. marplatensis and A. pulmonis. Antimicrobial susceptibilities were determined by the agar dilution method according to CLSI guidelines. Piperacillin, piperacillin/tazobactam and carbapenems were the most active antibiotics. However, the emergence of carbapenem-resistant isolates was detected. In conclusion, prompt and accurate identification tools were necessary to determine that different Achromobacter species may colonize/infect the airways of patients with CF. Moreover, antimicrobial therapy should be administered based on the susceptibility profile of individual Achromobacter sp. isolates.


Assuntos
Achromobacter/isolamento & purificação , Fibrose Cística/microbiologia , Achromobacter/classificação , Achromobacter/efeitos dos fármacos , Achromobacter/genética , Antibacterianos/farmacologia , Argentina , Farmacorresistência Bacteriana , Humanos , Fenótipo
8.
Int J Syst Evol Microbiol ; 70(1): 530-536, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31613739

RESUMO

Strain LMG 30378T was isolated from a hydrogen-oxidizing bacteria enrichment reactor inoculated with forest soil. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that this strain belonged to the genus Achromobacter. Multilocus sequence analysis combined with sequence analysis of a 765 bp nrd A gene fragment both showed Achromobacter agilis LMG 3411T and Achromobacter denitrificans LMG 1231T to be the closest-related neighbours to strain LMG 30378T. Genome sequence analysis revealed a draft genome of 6.81 Mb with a G+C content of 67.2 mol%. In silico DNA-DNA hybridization with A. denitrificans LMG 1231T and A. agilis LMG 3411T showed 42.7 and 42.5% similarity, respectively, confirming that strain LMG 30378T represented a novel Achromobacter species. Phenotypic and metabolic characterization revealed acid phosphatase activity and the absence of phosphoamidase activity as distinctive features. The draft genome composes all necessary metabolic components to fix carbon dioxide and to oxidize molecular hydrogen, suggesting that strain LMG 30378T is a key organism in the enrichment reactor. Together, these data demonstrate that strain LMG 30378T represents a novel species of the genus Achromobacter, for which the name Achromobacter veterisilvae sp. nov. is proposed. The type strain is LMG 30378T (=CCUG 71558T).


Assuntos
Achromobacter/classificação , Reatores Biológicos/microbiologia , Filogenia , Microbiologia do Solo , Achromobacter/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Bélgica , DNA Bacteriano/genética , Ácidos Graxos/química , Florestas , Hidrogênio , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
9.
PLoS One ; 14(12): e0226155, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31860658

RESUMO

Exploration of diverse environmental samples for plant growth-promoting microbes to fulfill the increasing demand for sustainable agriculture resulted in increased use of bacterial biofertilizer. We aimed for the isolation of plant growth-promoting as well as antibiotic sensitive bacteria from bovine manure samples. The basic theme of our study is to highlight potentials of bacteria in manure and the unchecked risk associated with the application of manure i.e. introducing antibiotic-resistant microbial flora, as fertilizer. Fifty-two, morphologically distinct isolates; from eight different manure samples, were subjected to plant growth-promoting parametric tests along with antibiotic resistance. Thirteen antibiotic sensitive bacterial strains with potentials of plant growth promotion further characterized by 16S rRNA ribotyping and the identified genera were Stenotrophomonas, Achromobacter, Pseudomonas, and Brevibacillus. Successful radish seeds germination under sterile in-vitro conditions showed the potential of selected bacterial isolates as plant growth-promoting bacteria. The results of this study confirmed plant growth-promoting characteristics of bovine manures' bacterial strains along with an alarming antibiotic resistance load which comprises 75% of bacterial isolated population. Our study showed distinct results of un-explored manure bacterial isolates for plant growth promotion and flagged ways associated with unchecked manure application in agriculture soil through high load of antibiotic resistant bacteria.


Assuntos
Bactérias/classificação , Esterco/microbiologia , RNA Ribossômico 16S/genética , Raphanus/crescimento & desenvolvimento , Achromobacter/classificação , Achromobacter/isolamento & purificação , Achromobacter/fisiologia , Agricultura/métodos , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Brevibacillus/classificação , Brevibacillus/isolamento & purificação , Brevibacillus/fisiologia , Bovinos , Fertilizantes , Germinação , Testes de Sensibilidade Microbiana , Pseudomonas/classificação , Pseudomonas/isolamento & purificação , Pseudomonas/fisiologia , Raphanus/microbiologia , Microbiologia do Solo , Stenotrophomonas/classificação , Stenotrophomonas/isolamento & purificação , Stenotrophomonas/fisiologia
10.
Sci Total Environ ; 664: 1030-1038, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30901777

RESUMO

The Yellow River Delta (YRD), being close to Shengli Oilfield, is at high risk for petroleum oil pollution. The aim of this study was to isolate halotolerant phenanthrene (PHE) degrading bacteria for dealing with this contaminates in salinity environment. Two bacterial strains assigned as FM6-1 and FM8-1 were successfully screened from oil contaminated soil in the YRD. Morphological and molecular analysis suggested that strains FM6-1 and FM8-1 were belonging to Delftia sp. and Achromobacter sp., respectively. Bacterial growth of both strains was not dependent on NaCl, however, grew well under extensive NaCl concentration. The optimum NaCl concentration for bacterial production of strain FM8-1 was 4% (m/v), whereas for strain FM6-1, growth was not affected within 2.5% NaCl. Both strains could use the tested aromatic hydrocarbons (naphthalene, phenanthrene, fluoranthene and pyrene) and aliphatic hydrocarbons (C12, C16, C20 and C32) as sole carbon source. The optimized biodegradation conditions for strain FM6-1 were pH 7, 28 °C and 2% NaCl, for strain FM8-1 were pH 8, 28 °C and 2.5% NaCl. The highest biodegradation rate of strains FM6-1 and FM8-1 was found at 150 mg/L PHE and 200 mg/L, respectively. In addition, strainsFM8-1 showed a superior biodegradation ability to strain FM6-1 at each optimized condition. The PHE biodegradation process by both strains well fitted to first-order kinetic models and the k1 values were calculated to be 0.1974 and 0.1070 per day. Strain FM6-1 metabolized PHE via a "phthalic acid" route, while strain FM8-1 metabolized PHE through the "naphthalene" route. This project not only obtained two halotolerant petroleum hydrocarbon degraders but also provided a promising remediation approach for solving oil pollutants in salinity environments.


Assuntos
Achromobacter/metabolismo , Delftia/metabolismo , Poluição por Petróleo/análise , Fenantrenos/metabolismo , Poluentes do Solo/metabolismo , Achromobacter/classificação , Achromobacter/genética , Biodegradação Ambiental , China , Delftia/classificação , Delftia/genética , Filogenia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
11.
J Basic Microbiol ; 59(3): 238-248, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30600533

RESUMO

A biosurfactant, produced by Achromobacter sp. TMB1 is reported through this investigation having physiochemical properties useful for operational and remedial activities in petroleum industries. The strain isolated from soils of local petrol pumps when allowed to grow in glucose containing mineral salts media (MSM) in ambient environment that is, 30 °C and varying pH in between 5.5 and 7.2, showed surface tension reduction as low as 34.25 dyne cm-1 at an interval of 48-72 h. Taguchi experiment confirmed the contribution of glucose, yeast extracts, and NaNO3 concentration on biosurfactant production. FTIR and 1 H NMR analysis of culture supernatant obtained after acid precipitation and solvent extraction methods revealed the glycolipid nature of the extracted compounds. HR-LCMS study further revealed the presence of 10 different types of mono- and di-rhamnolipids congeners with the fatty acids carbon length C8-12 . The isolated biosurfactant shows functional stability in the temperature range 20-100 °C and pH range 2-12 while maintaining the structural integrity till 550 °C (TGA-DSC), strongly suggests its potential applications in petroleum industries.


Assuntos
Achromobacter/química , Glicolipídeos/biossíntese , Glicolipídeos/química , Indústria de Petróleo e Gás , Tensoativos/química , Achromobacter/classificação , Achromobacter/crescimento & desenvolvimento , Achromobacter/metabolismo , Ácidos Graxos , Hidrocarbonetos/isolamento & purificação , Concentração de Íons de Hidrogênio , Filogenia , Microbiologia do Solo , Propriedades de Superfície , Temperatura
12.
Ecotoxicol Environ Saf ; 163: 205-214, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30055385

RESUMO

Despite many reports of the use of biodegradation to remove contaminants, the biodegradation of polycyclic aromatic hydrocarbons (PAHs) is challenging because of the hydrophobicities and low aqueous solubilities of most PAHs. In this study, phenanthrene (PHE) was used as a sole carbon and energy source to screen and identify Achromobacter sp. LH-1 for the production of biodemulsifiers that enhance the bioavailability and solubilization of PAHs. LH-1 achieved a 94% degradation rate and a 40% mineralization rate with 100 mg/L PHE. Additionally, LH-1 degraded various PAHs, and the factors that influenced the growth and PAHs degradation activity of LH-1 were not only the toxicities and structures of the substances but also the acclimation of LH-1 to these substances. Three kinetic models were used to describe the fermentation processes of cell growth, product formation and substrate degradation over time. Finally, multiple PHE degradation pathways were proposed to be utilized by strain LH-1.


Assuntos
Achromobacter/metabolismo , Poluentes Ambientais/metabolismo , Fermentação , Fenantrenos/metabolismo , Achromobacter/classificação , Biodegradação Ambiental , Reatores Biológicos , Cinética , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Solubilidade , Especificidade da Espécie
13.
FEMS Microbiol Ecol ; 94(4)2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29401267

RESUMO

Bacteria capable of simultaneous aerobic denitrification and phosphorus removal (SADPR) are promising for the establishment of novel one-stage wastewater treatment systems. Nevertheless, insights into the metabolic potential of SADPR-related bacteria are limited. Here, comprehensive metabolic models of two efficient SADPR bacteria, Achromobacter sp. GAD3 and Agrobacterium sp. LAD9, were obtained for the first time by high-throughput genome sequencing. With succinate as the preferred carbon source, both strains employed a complete TCA cycle as the major carbon metabolism for potentials of various organic acids and complex carbon oxidation. Complete and truncated aerobic denitrification routes were confirmed in GAD3 and LAD9, respectively, facilitated by all the major components of the electron transfer chain via oxidative phosphorylation. Comparative genome analysis revealed distinctive ecological niches involved in denitrification among different phylogenetic clades within Achromobacter and Agrobacterium. Excellent phosphorus removal capacities were contributed by inorganic phosphate uptake, polyphosphate synthesis and phosphonate metabolism. Additionally, the physiology of GAD3/LAD9 is different from that displayed by most available polyphosphate accumulating organisms, and reveals both strains to be more versatile, carrying out potentials for diverse organics degradation and outstanding SADPR capacity within a single organism. The functional exploration of SADPR bacteria broadens their significant prospects for application in concurrent aerobic carbon and nutrient removal.


Assuntos
Achromobacter/metabolismo , Agrobacterium/metabolismo , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Carbono/metabolismo , Nitrogênio/metabolismo , Fósforo/metabolismo , Achromobacter/classificação , Achromobacter/genética , Agrobacterium/classificação , Agrobacterium/genética , Bactérias Aeróbias/metabolismo , Desnitrificação , Genômica , Filogenia , Polifosfatos/metabolismo , Águas Residuárias/química , Águas Residuárias/microbiologia
14.
Microb Ecol ; 75(1): 1-6, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28634639

RESUMO

Honeybees are prone to parasite and pathogen infestations/infections due to their social colony life. Bacterial pathogens in particular lead to destructive infections of the brood. European foulbrood is caused by the bacterium Melissococcus plutonius in combination with several other Gram-positive bacteria (Achromobacter eurydice, Bacillus pumilus, Brevibacillus laterosporus, Enterococcus faecalis, Paenibacillus alvei, Paenibacillus dendritiformis) involved as secondary invaders following the initial infection. More than a century ago, A. eurydice was discovered to be associated with European foulbrood and morphologically and biochemically characterized. However, since the 1950s-1960s, only a few studies are known covering the biological relevance of this bacterium. Here, we review the biology, ecology, morphology, and biochemistry and discuss the still unclear systematic classification of A. eurydice.


Assuntos
Achromobacter/fisiologia , Abelhas/microbiologia , Achromobacter/classificação , Achromobacter/genética , Achromobacter/isolamento & purificação , Animais , Abelhas/crescimento & desenvolvimento , Europa (Continente) , Larva/crescimento & desenvolvimento , Larva/microbiologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-28611955

RESUMO

Achromobacter spp. are recognized as emerging pathogens in hospitalized as well as in cystic fibrosis (CF) patients. From 2012 to 2015, we collected 69 clinical isolates (41 patient) of Achromobacter spp. from 13 patients with CF (CF isolates, n = 32) and 28 patients receiving care for other health conditions (non-CF isolates, n = 37). Molecular epidemiology and virulence potential of isolates were examined. Antimicrobial susceptibility, motility, ability to form biofilms and binding affinity to mucin, collagen, and fibronectin were tested to assess their virulence traits. The nrdA gene sequencing showed that A. xylosoxidans was the most prevalent species in both CF and non-CF patients. CF patients were also colonized with A. dolens/A. ruhlandii, A. insuavis, and A. spiritinus strains while non-CF group was somewhat less heterogenous, although A. insuavis, A. insolitus, and A. piechaudii strains were detected beside A. xylosoxidans. Three strains displayed clonal distribution, one among patients from the CF group and two among non-CF patients. No significant differences in susceptibility to antimicrobials were observed between CF and non-CF patients. About one third of the isolates were classified as strong biofilm producers, and the proportion of CF and non-CF isolates with the ability to form biofilm was almost identical. CF isolates were less motile compared to the non-CF group and no correlation was found between swimming phenotype and biofilm formation. On the other hand, CF isolates exhibited higher affinity to bind mucin, collagen, and fibronectin. In generall, CF isolates from our study exhibited in vitro properties that could be of importance for the colonization of CF patients.


Assuntos
Achromobacter/genética , Achromobacter/fisiologia , Fibrose Cística/complicações , Infecções por Bactérias Gram-Negativas/microbiologia , Epidemiologia Molecular , Virulência/genética , Achromobacter/classificação , Achromobacter/isolamento & purificação , Adesinas Bacterianas , Adolescente , Adulto , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Criança , Pré-Escolar , Farmacorresistência Bacteriana , Feminino , Genes Bacterianos/genética , Genótipo , Infecções por Bactérias Gram-Negativas/complicações , Humanos , Lactente , Recém-Nascido , Locomoção , Masculino , Testes de Sensibilidade Microbiana , Família Multigênica , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Adulto Jovem
17.
J Microbiol ; 55(6): 428-434, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28551873

RESUMO

A novel strain DCY105T was isolated from soil collected from the rhizosphere of ginseng (Panax ginseng), in Gochang, Republic of Korea. Strain DCY105T is Gram-reaction-negative, white, non-motile, non-flagellate, rod-shaped and aerobic. The bacteria grow optimally at 30°C, pH 6.5-7.0 and in the absence of NaCl. Phylogenetically, strain DCY105T is most closely related to Achromobacter marplatensis LMG 26219T (96.81%). The DNA G+C content of strain DCY105T was 64.4 mol%. Ubiquinone 8 was the major respiratory quinone, and phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol were amongst the major polar lipids. C16:00, C8:03OH and iso-C17:03OH were identified as the major fatty acids present in DCY105T. The results of physiological and biochemical tests allowed strain DCY105T to be differentiated phenotypically from other recognized species belonging to the genus Achromobacter. Therefore, it is suggested that the newly isolated organism represents a novel species, for which the name Achromobacter panacis sp. nov. is proposed with the type strain designated as DCY105T (=CCTCCAB 2015193T =KCTC 42751T).


Assuntos
Achromobacter , Panax/microbiologia , Achromobacter/classificação , Achromobacter/genética , Achromobacter/isolamento & purificação , Composição de Bases/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , RNA Ribossômico 16S/genética , República da Coreia , Rizosfera , Análise de Sequência de DNA , Microbiologia do Solo
18.
J Clin Microbiol ; 55(7): 2074-2085, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28446570

RESUMO

Achromobacter species are increasingly being detected in cystic fibrosis (CF) patients, with an unclear epidemiology and impact. We studied a cohort of patients attending a Canadian adult CF clinic who had positive sputum cultures for Achromobacter species in the period from 1984 to 2013. Infection was categorized as transient or persistent (≥50% positive cultures for 1 year). Those with persistent infection were matched 2:1 with age-, sex-, and time-matched controls without a history of Achromobacter infection, and mixed-effects models were used to assess pulmonary exacerbation (PEx) frequency and lung function decline. Isolates from a biobank were retrospectively assessed, identified to the species level by nrdA sequencing, and genotyped using pulsed-field gel electrophoresis (PFGE). Thirty-four patients (11% of those in our clinic), with a median age of 24 years (interquartile range [IQR], 20.3 to 29.8 years), developed Achromobacter infection. Ten patients (29%) developed persistent infection. Persistence did not denote permanence, as most patients ultimately cleared infection, often after years. Patients were more likely to experience PEx at incident isolation than at prior or subsequent visits (odds ratio [OR], 2.7 [95% confidence interval {CI}, 1.2 to 6.7]; P = 0.03). Following persistent infection, there was no difference in annual lung function decline (-1.08% [95% CI, -2.73 to 0.57%] versus -2.74% [95% CI, -4.02 to 1.46%]; P = 0.12) or the odds of PEx (OR, 1.21 [95% CI, 0.45 to 3.28]; P = 0.70). Differential virulence among Achromobacter species was not observed, and no cases of transmission occurred. We demonstrated that incident Achromobacter infection was associated with a greater risk of PEx; however, neither transient nor chronic infection was associated with a worsened long-term prognosis. Large, multicenter studies are needed to clarify the clinical impact, natural history, and transmissibility of Achromobacter.


Assuntos
Achromobacter/isolamento & purificação , Fibrose Cística/complicações , Infecções por Bactérias Gram-Negativas/epidemiologia , Achromobacter/classificação , Achromobacter/genética , Adolescente , Adulto , Feminino , Seguimentos , Infecções por Bactérias Gram-Negativas/patologia , Humanos , Masculino , América do Norte/epidemiologia , Prevalência , Testes de Função Respiratória , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
19.
Pathog Dis ; 75(4)2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28369432

RESUMO

Achromobacter insolitus is a newly described, Gram-negative, small (1-2 mm long) and coccoid pathogen that has been isolated from leg wound. Due to its potential threat to human beings, the type strain of this species LMG 6003T was completely sequenced in this study. The genomic analysis revealed that the genome of LMG 6003T consists of one circular DNA chromosome of 6 492 697 bp with a GC content of 65.10%. The entire genome contains 6208 predicted coding genes, 61 tRNAs and 13 rRNA genes. Comparative genome analysis between LMG 6003T and another selected 10 sequenced Achromobacter revealed that 725 genes only exist in LMG 6003T. In particular, these genes include several important pathogenic-related genes such as Type IV prepilin peptidase (TadV/CpaA), Type VI secretion lipoprotein (VasD) and type 1 fimbriae major subunit (FimA). Genomic island (GI) analysis also suggests the existence of GIs in LMG 6003T. All these results strongly suggest the unique genomic features in LMG 6003T against other Achromobacter species. This report will provide us with an extended understanding of A. insolitus at the genomic level and would be helpful for understanding the evolution of the Achromobacter genus.


Assuntos
Achromobacter/genética , Mapeamento Cromossômico , DNA Bacteriano/genética , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Achromobacter/classificação , Achromobacter/isolamento & purificação , Composição de Bases , DNA Bacteriano/metabolismo , DNA Circular/genética , DNA Circular/metabolismo , Endopeptidases/genética , Endopeptidases/metabolismo , Proteínas de Fímbrias/genética , Proteínas de Fímbrias/metabolismo , Ontologia Genética , Ilhas Genômicas , Humanos , Perna (Membro)/microbiologia , Anotação de Sequência Molecular , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , Sistemas de Secreção Tipo VI/genética , Sistemas de Secreção Tipo VI/metabolismo , Sequenciamento Completo do Genoma
20.
Diagn Microbiol Infect Dis ; 88(1): 58-61, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28215715

RESUMO

Achromobacter animicus (A. animicus) is an aerobic, motile, gram-negative, non-fermenting small bacillus that can also grow anaerobically with potassium nitrate. It has been isolated from sputum of humans suffering from respiratory infections. Literature regarding the role of A. animicus in wound infections is limited. We report a first case of a chronic post-traumatic wound infection caused by a multidrug-resistant A. animicus in a street child from Africa and accompanied diagnostic challenges.


Assuntos
Achromobacter/isolamento & purificação , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/microbiologia , Infecção dos Ferimentos/diagnóstico , Infecção dos Ferimentos/microbiologia , Achromobacter/classificação , Achromobacter/efeitos dos fármacos , Achromobacter/genética , Adolescente , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Análise por Conglomerados , Farmacorresistência Bacteriana Múltipla , Infecções por Bactérias Gram-Negativas/patologia , Jovens em Situação de Rua , Humanos , Masculino , Filogenia , Análise de Sequência de DNA , Homologia de Sequência , Tanzânia , Infecção dos Ferimentos/patologia
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