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Clinical Infectious Diseases : An... Oct 2021Treatment options for Achromobacter xylosoxidans are limited. Eight cystic fibrosis patients with A. xylosoxidans were treated with 12 cefiderocol courses. Pretreatment...
Treatment options for Achromobacter xylosoxidans are limited. Eight cystic fibrosis patients with A. xylosoxidans were treated with 12 cefiderocol courses. Pretreatment in vitro resistance was seen in 3 of 8 cases. Clinical response occurred after 11 of 12 treatment courses. However, microbiologic relapse was observed after 11 of 12 treatment courses, notably without emergence of resistance.
Topics: Achromobacter denitrificans; Adult; Anti-Bacterial Agents; Cephalosporins; Child; Cystic Fibrosis; Gram-Negative Bacterial Infections; Humans; Cefiderocol
PubMed: 33313656
DOI: 10.1093/cid/ciaa1847 -
Plant Disease Feb 2024Scrub titi (), broadleaf semi-evergreen shrub, is endemic to central Florida. However, its smaller stature, lustrous, dark-green leaves and abundance of white racemes in...
Scrub titi (), broadleaf semi-evergreen shrub, is endemic to central Florida. However, its smaller stature, lustrous, dark-green leaves and abundance of white racemes in late spring make it a potential candidate for future use in Southeastern U.S. landscapes. Three-years-old container grown plants maintained in a shade house at the Nursery Research Center, McMinnville, TN exhibited black leaf lesions and brown stem lesions (Fig. 1a) in April 2023. The disease severity was 25% of the shoot area and the disease incidence was 10% out of 60 plants. Symptomatic stem and leaf tissues were surface sterilized with 0.525% NaOCl for 1 min. Bacterial colonies were white-colored, opaque, round with smooth edges on lysogen broth agar medium after 2 days of incubation at 28°C. Bacteria were gram-negative and non-fluorescent on King's B. Esculin, catalase, and oxidase tests were positive but arginine dihydrolase and gelatine hydrolysis were negative. Bacterial identity was confirmed by sequencing of DNA from pure cultures (strains FBG5290 and FBG5294). The 16S ribosomal RNA, RNA polymerase sigma factor (), enolase (), and NADH-quinone oxidoreductase subunit L () genes were amplified and sequenced using the primers 8F/1492R (Galkiewicz et al. 2008), rpoDpF/R (Sarkar and Guttman 2004), enoP1/P2 and nuoLP1/P2 (Spilker et al. 2012), respectively. The sequences were deposited in GenBank with acc. nos.: OR689356, OR689357 (16S); OR751366, OR751367 (); OR792456, OR792457 (); and OR792458, OR792459 (). The closest identified species to our two identical strains was (CP054571), showing 99.6%, 95.2%, 96.2%, and 95.0% identity with >99% coverage to the above mentioned gene sequences, respectively. Phylogenetic analysis, using concatenated sequences along with the genome sequences of other closely related taxa (Fig. 2), suggest that is presently the identified species, but given the results of the MLST, it may be that this organism will be classified as new species in the future. The pathogenicity of the strains was confirmed on 1-year-old by inoculating five plants per strain. Stems were inoculated by depositing 15 µl of bacterial suspension (1x10 CFU/mL) into the stem wounded using a scalpel. The inoculation sites were covered with moist cotton and wrapped with Parafilm. Inoculation was also performed on three leaves per plant by using a needleless syringe to infiltrate bacteria into the intercellular spaces (1x10 CFU/mL). Sterile water was used for five control plants. Plants were kept in a greenhouse at 21-23°C, 70% RH, and 16-h photoperiod. All inoculated plants showed brown lesions in stems (Fig. 1b and 1c) and leaves (Fig. 1d) 7-10 days after inoculation, while control plants remained asymptomatic (Fig. 1e and 1f). The bacteria were re-isolated from inoculated plants and confirmed as using morphological and molecular methods. spp. are commonly known as human pathogens, and cross-kingdom pathogenic bacterium in animal (mice) and fungi () (Ye et al. 2018). However, was recently reported as the causal agent of stem rot of in China (Wei et al. 2023). To our knowledge, this is the first report of causing bacterial stem and leaf blight of in Tennessee and the U.S. Identification of this novel disease lays the foundation development of effective management strategies.
PubMed: 38345542
DOI: 10.1094/PDIS-01-24-0005-PDN -
Journal of Cystic Fibrosis : Official... May 2020A structured survey of the cystic fibrosis pathogens Achromobacter, Pandoraea and Ralstonia species from thirteen sentinel hospitals throughout England was undertaken by...
A structured survey of the cystic fibrosis pathogens Achromobacter, Pandoraea and Ralstonia species from thirteen sentinel hospitals throughout England was undertaken by Public Health England. One isolate per patient of these genera collected from CF patients during the seven-month survey period in 2015 was requested from participating hospitals. Species-level identification was performed using nrdA/gyrB sequence cluster analysis, and genotyping by pulsed-field gel electrophoresis. In total, 176 isolates were included in the survey; 138 Achromobacter spp. (78.4%), 29 Pandoraea spp. (16.5%) and 9 Ralstonia spp. (5.1%). Novel Achromobacter and Pandoraea clusters were identified. High levels of antimicrobial resistance were found, particularly among Pandoraea isolates. Genotyping analysis revealed considerable diversity, however one geographically-widespread cluster of A. xylosoxidans isolates from six hospitals was found, in addition to two other clusters, both comprising isolates from two hospitals, either derived from the same region (A. xylosoxidans), or from hospitals within the same city (P. apista).
Topics: Achromobacter denitrificans; Adult; Anti-Bacterial Agents; Burkholderiaceae; Child; Cross Infection; Cystic Fibrosis; Drug Resistance, Microbial; England; Epidemiological Monitoring; Female; Gram-Negative Bacterial Infections; Humans; Male; Microbial Sensitivity Tests; Multilocus Sequence Typing; Ralstonia; Respiratory Tract Infections
PubMed: 31862307
DOI: 10.1016/j.jcf.2019.11.005 -
Revista Chilena de Infectologia :... Aug 2012
Topics: Achromobacter denitrificans; Drug Resistance, Bacterial
PubMed: 23096549
DOI: 10.4067/S0716-10182012000400016 -
Pathogens (Basel, Switzerland) Jan 2019is an innately multidrug-resistant bacterium capable of forming biofilms in the respiratory tract of cystic fibrosis (CF) patients. During the transition from the...
is an innately multidrug-resistant bacterium capable of forming biofilms in the respiratory tract of cystic fibrosis (CF) patients. During the transition from the planktonic stage to biofilm growth, bacteria undergo a transcriptionally regulated differentiation. An isolate of cultured from the sputum of a CF patient was separated into sessile and planktonic stages in vitro, and the transcriptomes were compared. The selected genes of interest were subsequently inactivated, and flagellar motility was found to be decisive for biofilm formation in vitro. The spectrum of a new resistance-nodulation-cell division (RND)-type multidrug efflux pump (AxyEF-OprN) was characterized by inactivation of the membrane fusion protein. AxyEF-OprN is capable of extruding some fluoroquinolones (levofloxacin and ciprofloxacin), tetracyclines (doxycycline and tigecycline) and carpabenems (ertapenem and imipenem), which are classes of antimicrobials that are widely used for treatment of CF pulmonary infections.
PubMed: 30691200
DOI: 10.3390/pathogens8010014 -
Scientific Reports Oct 2021Arsenotrophic bacteria play an essential role in lowering arsenic contamination by converting toxic arsenite [As (III)] to less toxic and less bio-accumulative arsenate...
Arsenotrophic bacteria play an essential role in lowering arsenic contamination by converting toxic arsenite [As (III)] to less toxic and less bio-accumulative arsenate [As (V)]. The current study focused on the qualitative and electrocatalytic detection of the arsenite oxidation potential of an arsenite-oxidizing bacteria A. xylosoxidans BHW-15 (retrieved from As-contaminated tube well water), which could significantly contribute to arsenic detoxification, accumulation, and immobilization while also providing a scientific foundation for future electrochemical sensor development. The minimum inhibitory concentration (MIC) value for the bacteria was 15 mM As (III). Scanning Electron Microscopy (SEM) investigation validated its intracellular As uptake capacity and demonstrated a substantial association with the MIC value. During the stationary phase, the strain's As (III) transformation efficiency was 0.0224 mM/h. Molecular analysis by real-time qPCR showed arsenite oxidase (aioA) gene expression increased 1.6-fold in the presence of As (III) compared to the untreated cells. The immobilized whole-cell also showed As (III) conversion up to 18 days. To analyze the electrochemical oxidation in water, we developed a modified GCE/P-Arg/ErGO-AuNPs electrode, which successfully sensed and quantified conversion of As (III) into As (V) by accepting electrons; implying a functional As oxidase enzyme activity in the cells. To the best of our knowledge, this is the first report on the electrochemical observation of the As-transformation mechanism with Achromobacter sp. Furthermore, the current work highlighted that our isolate might be employed as a promising candidate for arsenic bioremediation, and information acquired from this study may be helpful to open a new window for the development of a cost-effective, eco-friendly biosensor for arsenic species detection in the future.
Topics: Achromobacter denitrificans; Arsenic; Bioaccumulation; Electrochemistry; Gene Expression Regulation, Bacterial; Inactivation, Metabolic; Oxidoreductases
PubMed: 34716390
DOI: 10.1038/s41598-021-00745-1 -
Microbiome Jun 2017Although culture-independent methods have paved the way for characterization of the lung microbiome, the dynamic changes in the lung microbiome from neonatal stage to...
BACKGROUND
Although culture-independent methods have paved the way for characterization of the lung microbiome, the dynamic changes in the lung microbiome from neonatal stage to adult age have not been investigated.
RESULTS
In this study, we tracked changes in composition and diversity of the lung microbiome in C57BL/6N mice, starting from 1-week-old neonates to 8-week-old mice. Towards this, the lungs were sterilely excised from mice of different ages from 1 to 8 weeks. High-throughput DNA sequencing of the 16S rRNA gene followed by composition and diversity analysis was utilized to decipher the microbiome in these samples. Microbiome analysis suggests that the changes in the lung microbiome correlated with age. The lung microbiome was primarily dominated by phyla Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria in all the stages from week 1 to week 8 after birth. Although Defluvibacter was the predominant genus in 1-week-old neonatal mice, Streptococcus became the dominant genus at the age of 2 weeks. Lactobacillus, Defluvibacter, Streptococcus, and Achromobacter were the dominant genera in 3-week-old mice, while Lactobacillus and Achromobacter were the most abundant genera in 4-week-old mice. Interestingly, relatively greater diversity (at the genus level) during the age of 5 to 6 weeks was observed as compared to the earlier weeks. The diversity of the lung microbiome remained stable between 6 and 8 weeks of age.
CONCLUSIONS
In summary, we have tracked the development of the lung microbiome in mice from an early age of 1 week to adulthood. The lung microbiome is dominated by the phyla Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria. However, dynamic changes were observed at the genus level. Relatively higher richness in the microbial diversity was achieved by age of 6 weeks and then maintained at later ages. We believe that this study improves our understanding of the development of the mice lung microbiome and will facilitate further analyses of the role of the lung microbiome in chronic lung diseases.
Topics: Achromobacter; Actinobacteria; Aging; Animals; Animals, Newborn; Bacteroidetes; Firmicutes; Genetic Variation; High-Throughput Nucleotide Sequencing; Lactobacillus; Lung; Metagenome; Mice; Mice, Inbred C57BL; Microbiota; Proteobacteria; RNA, Ribosomal, 16S; Respiratory System
PubMed: 28637485
DOI: 10.1186/s40168-017-0277-3 -
International Journal of Molecular... Aug 2022spp. can establish occasional or chronic lung infections in patients with cystic fibrosis (CF). Chronic colonization has been associated with worse prognosis...
spp. can establish occasional or chronic lung infections in patients with cystic fibrosis (CF). Chronic colonization has been associated with worse prognosis highlighting the need to identify markers of bacterial persistence. To this purpose, we analyzed phenotypic features of 95 spp. isolates from 38 patients presenting chronic or occasional infection. Virulence was tested in larvae, cytotoxicity was tested in human bronchial epithelial cells, biofilm production in static conditions was measured by crystal violet staining and susceptibility to selected antibiotics was tested by the disk diffusion method. The presence of genetic loci associated to the analyzed phenotypic features was evaluated by a genome-wide association study. Isolates from occasional infection induced significantly higher mortality of larvae and showed a trend for lower cytotoxicity than chronic infection isolates. No significant difference was observed in biofilm production among the two groups. Additionally, antibiotic susceptibility testing showed that isolates from chronically-infected patients were significantly more resistant to sulfonamides and meropenem than occasional isolates. Candidate genetic biomarkers associated with antibiotic resistance or sensitivity were identified. spp. strains isolated from people with chronic and occasional lung infection exhibit different virulence and antibiotic susceptibility features, which could be linked to persistence in CF lungs. This underlines the possibility of identifying predictive biomarkers of persistence that could be useful for clinical purposes.
Topics: Achromobacter; Anti-Bacterial Agents; Biomarkers; Cystic Fibrosis; Drug Resistance, Bacterial; Genome-Wide Association Study; Humans; Microbial Sensitivity Tests
PubMed: 36012535
DOI: 10.3390/ijms23169265 -
Iranian Journal of Microbiology Jun 2023The study aimed to investigate whether IA strain biofilm formation, which contributes to antibiotic resistance, could be enhanced by readily available nutrient sources...
BACKGROUND AND OBJECTIVES
The study aimed to investigate whether IA strain biofilm formation, which contributes to antibiotic resistance, could be enhanced by readily available nutrient sources like carbohydrates and environmental factors such as pH and NaCl. Additionally, the study aimed to identify any inherent genes that support biofilm formation in this strain, which is an opportunistic pathogen that affects immunocompromised patients and is resistant to many antibiotics.
MATERIALS AND METHODS
Biofilm growth in different carbohydrate, pH, and NaCl concentrated media was measured using crystal violet microtiter assay. All the treatments were subjected to biostatistics analysis for normality, Test of Homogeneity, one way ANOVA analysis. Whole-genome sequencing of our IA strain was conducted to identify various gene sequences.
RESULTS
Biofilm formation was measured at different carbohydrate concentrations, and the optimum biofilm formation was observed at 3M glucose and 0.5M NaCl, while the lowest results were seen at 2M maltose concentration. Whole-genome sequencing identified potential genes involved in biofilm formation, pathogenicity, protein metabolism, flagellar motility, cell wall component synthesis, and a multidrug efflux pump.
CONCLUSION
These findings suggest that biofilm formation is influenced by extrinsic and intrinsic factors, which could aid in the development of effective treatments for resistant infections.
PubMed: 37448677
DOI: 10.18502/ijm.v15i3.12902 -
Microorganisms Aug 2023A Gram-stain-negative, aerobic, motile by gliding, and rod-shaped bacterium, designated IMCC34845, was isolated from a freshwater stream in the Republic of Korea. The...
A Gram-stain-negative, aerobic, motile by gliding, and rod-shaped bacterium, designated IMCC34845, was isolated from a freshwater stream in the Republic of Korea. The results of 16S rRNA gene-based phylogenetic analyses showed that strain IMCC34845 was affiliated with the genus and was most closely related to 'Achromobacter panacis' DCY105 (100%) and LF4-65 (98.9%). The whole-genome sequence of strain IMCC34845 was 3.2 Mbp in size with a 51.5% DNA G+C content. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain IMCC34845 and 'Achromobacter panacis' KCTC 42751 were 77.7% and 20.7%, respectively, revealing that they are independent species. Moreover, the strains IMCC34845 and KCTC 42751 exhibited ≤ 72.5% ANI and ≤18.5% dDDH values with closely related species LF4-65, further supporting that the two strains represent each novel species of the genus. The major respiratory quinone of strain IMCC34845 was ubiquinone-8 (Q-8), and the predominant cellular fatty acids were C (41.3%) and C cyclo (34.5%). The major polar lipids of the strain were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, unidentified phospholipids, and unidentified aminolipids. Based on the phylogenetic, genomic, physiological, and chemotaxonomic characteristics, strain IMCC34845 was considered to represent a novel species within the genus , for which the name sp. nov. is proposed. The type of strain is IMCC34845 (=KCTC 92920 = NBRC 114902). Furthermore, based on the taxonomic data, 'Achromobacter panacis' is proposed to be reclassified as comb. nov.
PubMed: 37763994
DOI: 10.3390/microorganisms11092150