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Frontiers in Microbiology 2023is a genus of gram-negative bacteria that can act as opportunistic pathogens. Recent studies have revealed that some species of show inherent resistance to β-lactams,...
BACKGROUND
is a genus of gram-negative bacteria that can act as opportunistic pathogens. Recent studies have revealed that some species of show inherent resistance to β-lactams, but the resistance mechanisms of have rarely been reported.
METHOD
The bacterium was isolated using standard laboratory procedures. The agar dilution method was used to determine the minimum inhibitory concentrations (MICs). Genome sequencing was performed using the PacBio RS II and Illumina HiSeq 2500 platforms, and the Comprehensive Antibiotic Resistance Database (CARD) was used to annotate the drug resistance genes. The localization of the novel β-lactamase AMZ-1 was determined, and its characteristics were determined via molecular cloning and enzyme kinetic analysis. The phylogenetic relationship and comparative genomic analysis of the resistance gene-related sequences were also analyzed.
RESULT
Y3, isolated from a goose on a farm in Wenzhou, showed resistance to multiple antibiotics, including penicillins and cephalosporins. showed resistance to amoxicillin, penicillin G, ampicillin, cephalothin and cefoxitin, and the resistance activity could be inhibited by β-lactamase inhibitors. Enzyme kinetic analysis results showed that AMZ-1 has hydrolytic activity against a wide range of substrates, including cephalothin, amoxicillin, penicillin G, and cefoxitin but not ampicillin. The hydrolytic activity of AMZ-1 was greatly inhibited by avibactam but much more weakly inhibited by tazobactam. Mobile genetic elements could not be found around the -like genes, which are conserved on the chromosomes of bacteria of the genus .
CONCLUSION
In this study, a novel AmpC gene, , from the animal-origin bacterium Y3 was identified and characterized. It conferred resistance to some penicillins and first- and second-generation cephalosporins. The identification of this novel resistance gene will be beneficial for the selection of effective antimicrobials to treat associated infections.
PubMed: 37808287
DOI: 10.3389/fmicb.2023.1252427 -
Microorganisms Aug 2023In this study, an acclimated manganese-oxidizing bacteria (MnOB) consortium, QBS-1, was enriched in an acid mine area; then, it was used to eliminate Mn(Ⅱ) in...
In this study, an acclimated manganese-oxidizing bacteria (MnOB) consortium, QBS-1, was enriched in an acid mine area; then, it was used to eliminate Mn(Ⅱ) in different types of wastewater. QBS-1 presented excellent Mn removal performance between pH 4.0 and 8.0, and the best Mn-removal efficiency was up to 99.86% after response surface methodology optimization. Unlike other MnOB consortia, the core bacteria of QBS-1 were and , which might play vital roles in Mn removal. Besides that, adsorption, co-precipitation and electrostatic binding by biological manganese oxides could further promote Mn elimination. Finally, the performance of the Mn biofilter demonstrated that QBS-1 was an excellent inoculant, which indicates good potential for removing Mn contamination steadily and efficiently.
PubMed: 37764029
DOI: 10.3390/microorganisms11092185 -
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 -
Animals : An Open Access Journal From... Sep 2023(1) Fine particulate matter (PM) seriously affects the respiratory tract health of both animals and humans. Growing evidence indicates that the pulmonary microbiota is...
(1) Fine particulate matter (PM) seriously affects the respiratory tract health of both animals and humans. Growing evidence indicates that the pulmonary microbiota is involved in the development of respiratory tract health; however, there is still much that is unknown about the specific changes of pulmonary microbiota caused by PM in broilers. (2) In this experiment, a total of 48 broilers were randomly divided into a control group and PM-exposure group. The experiment lasted for 21 days. Microbiota, inflammation biomarkers, and histological markers in the lungs were determined. (3) On the last day of the experiment, PM significantly disrupted the structure of lung tissue and induced chronic pulmonary inflammation by increasing IL-6, TNFα, and IFNγ expression and decreasing IL-10 expression. PM exposure significantly altered the α and β diversity of pulmonary microbiota. At the phylum level, PM exposure significantly decreased the abundance and increased the abundance of and . At the genus level, PM exposure significantly increased the abundance of , , , and . We also observed positive associations of the above altered genera with lung TNFα and IFNγ expression. (4) The results suggest that PM perturbs the pulmonary microbiota and induces chronic inflammation, and the pulmonary microbiota possibly contributes to the development of lung inflammation.
PubMed: 37760262
DOI: 10.3390/ani13182862 -
Gut Pathogens Sep 2023Patients with liver cirrhosis (LC) are prone to gastric mucosa damage. We investigated the alterations of gastric mucosa in LC patients and their possible mechanisms...
BACKGROUND
Patients with liver cirrhosis (LC) are prone to gastric mucosa damage. We investigated the alterations of gastric mucosa in LC patients and their possible mechanisms through multi-omics.
RESULTS
We observed significant gastric mucosa microbial dysbiosis in LC subjects. Gastric mucosal microbiomes of LC patients contained a higher relative abundance of Streptococcus, Neisseria, Prevotella, Veillonella, and Porphyromonas, as well as a decreased abundance in Helicobacter and Achromobacter, than control subjects. The LC patients had higher levels of bile acids (BAs) and long-chain acylcarnitines (long-chain ACs) in serum. The gastric mucosal microbiomes were associated with serum levels of BAs and long-chain ACs. Transcriptome analyses of gastric mucosa revealed an upregulation of endothelial cell specific molecule 1, serpin family E member 1, mucin 2, caudal type homeobox 2, retinol binding protein 2, and defensin alpha 5 in LC group. Besides, the bile secretion signaling pathway was significantly upregulated in the LC group.
CONCLUSIONS
The alterations in the gastric mucosal microbiome and transcriptome of LC patients were identified. The impaired energy metabolism in gastric mucosal cells and bile acids might aggravate the inflammation of gastric mucosa and even exacerbate the Correa's cascade process. The gastric mucosal cells might reduce bile acid toxicity by bile acid efflux and detoxification.
TRIAL REGISTRATION
ChiCTR2100051070.
PubMed: 37752551
DOI: 10.1186/s13099-023-00571-y -
The Science of the Total Environment Jan 2024The disposal of mining wastes that contain cyanide are dumped in tailings from gold extraction is a public concern in mining countries such as South Africa. Many studies...
The disposal of mining wastes that contain cyanide are dumped in tailings from gold extraction is a public concern in mining countries such as South Africa. Many studies have shown the potential of microorganisms to degrade cyanide. However, no in-situ exploration, in tailings contaminated with cyanide, of the capability of indigenous microorganisms to act as a natural barrier for cyanide attenuation has been performed. Here we aim to combine geochemical and metagenomics techniques to reveal the genomic machinery of indigenous bacteria to degrade cyanide in gold tailings. Indigenous bacteria (i.e., Alicyclobacillus, Sulfobacillus, Acinetobacter, Achromobacter, and among others) pose the genomic machinery to trigger hydrolytic cyanide degradation using enzymes such as nitrilase, nitrile hydratase (Nhase) and thiocyanate. It seems that the lack of nitrogen sources induces the use of cyanide, which would contribute to its natural attenuation in the gold tailings. Therefore, the bacteria identified could represent the first barrier for the detoxification and degradation of cyanide in the outermost layer of the tailings.
Topics: Cyanides; Gold; Biodegradation, Environmental; South Africa
PubMed: 37741393
DOI: 10.1016/j.scitotenv.2023.167174 -
Frontiers in Microbiology 2023Hybrid biological-inorganic (HBI) systems show great promise as CO conversion platforms combining CO fixation by hydrogen-oxidizing bacteria (HOB) with water splitting....
Hybrid biological-inorganic (HBI) systems show great promise as CO conversion platforms combining CO fixation by hydrogen-oxidizing bacteria (HOB) with water splitting. Herein, halotolerant HOB were enriched using an HBI system with a high-ionic-strength medium containing 180 mM phosphate buffer to identify new biocatalysts. The reactors were inoculated with samples from saline environments and applied with a voltage of 2.0 V. Once an increase in biomass was observed with CO consumption, an aliquot of the medium was transferred to a new reactor. After two successive subcultures, strain H1_3_1 and strain H4_3_1 were isolated from the reactor media. Genome sequencing indicated the presence of genes for aerobic hydrogen-oxidizing chemolithoautotrophy and synthesis of the compatible solute hydroxyectoine in both strains. Furthermore, both strains produced hydroxyectoine in the reactors under the high-ionic-strength condition, suggesting the potential for new HBI systems using halotolerant HOB to produce high-value-added chemicals.
PubMed: 37711693
DOI: 10.3389/fmicb.2023.1254451 -
Frontiers in Microbiology 2023Increasing soil salinity depreciates the quantity of the crop produce. Looking at the tremendous potential of plant-associated microorganisms in salinity stress...
Colonization potential of endophytes from halophytic plants growing in the "Runn of Kutch" salt marshes and their contribution to mitigating salt stress in tomato cultivation.
Increasing soil salinity depreciates the quantity of the crop produce. Looking at the tremendous potential of plant-associated microorganisms in salinity stress mitigation, it would be very useful in exploring and deciphering salt-tolerant microorganisms from halophytic plants and their utilization in cultivated plants. With this aim, in the present study, four halophytic plants were taken from Rann of Kutch, and bacterial endophytes were isolated from different plant organs. These endophytes were characterized by plant growth and health promotion features. The molecular identification was done based on 16 s rRNA sequence similarity. It was found that the endophytic bacteria isolated from 4 different halophytes found sharing phylogenetic relatedness. Four potential endophytes 2H2, 2H18, 2H20, and 4H1 were tested in tomato for salinity stress alleviation. Changes in the levels of antioxidants were analyzed. Total chlorophyll, total phenolics, malondialdehyde, and proline content indicated reduced damage in the plant system due to salinity by the application of endophytes. All the treatments exhibited low levels of electrolyte leakage. The accumulation of enzymatic reactive oxygen species scavengers was assessed from the levels of peroxidase, catalase, superoxide dismutase, phenylalanine ammonia-lyase, ascorbate peroxidase, and guiacol peroxidase. The NBT and DAB staining confirmed the findings. The reduction in the accumulation of Na ions in tomato leaves was visualized using Sodium Green probes under CSLM and found to be lowest in 2H20 and 4H1 inoculated plants. The endophyte 2H20 was the most promising isolate. The colonization in tomato roots was confirmed using a cell tracker system. Results showed that the endophytes were found to have salinity stress mitigation traits. The efficiency could be further improved with the combination of other endophytes tested earlier.
PubMed: 37705729
DOI: 10.3389/fmicb.2023.1226149 -
International Journal of Molecular... Sep 2023Heavy metal contamination is among the most prominent environmental problems in China, posing serious threats to both ecosystem and human health. Among the diverse heavy...
Heavy metal contamination is among the most prominent environmental problems in China, posing serious threats to both ecosystem and human health. Among the diverse heavy metal contaminants, cadmium is the most serious. The whitefly is a cosmopolitan pest capable of causing severe damage to a broad range of agricultural crops, especially vegetables. At present, little is known about the effects of cadmium stress on , including on its bacterial and fungal communities. In the current study, we investigated the effects of cadmium on bacterial and fungal communities in whiteflies. Meta-barcode sequencing of the 16S rRNA gene revealed that the whitefly bacterial community contained 264 operational taxonomic units (OTUs) belonging to 201 known genera and 245 known species. The top five most frequent bacterial genera were , , , , and . Meta-barcode sequencing of the fungal ITS locus revealed that the whitefly fungal community contained 357 OTUs belonging to 187 known genera and 248 known species. The top five most frequent fungal genera were , , , , and . Cadmium exposure reduced the fungal OTU richness but increased the bacterial Shannon and Simpson diversity indices in whiteflies. In addition, upon exposure to cadmium, the microbial community composition in whiteflies changed significantly, with increased prevalence of the bacterial genera and and fungal genus . Our results indicate that the whitefly microbiota likely contributed to their adaptation and resistance to cadmium and suggested that whiteflies may contain microbes that could help remediate cadmium contamination in natural environments and agricultural fields.
Topics: Humans; Animals; Cadmium; Mycobiome; Hemiptera; RNA, Ribosomal, 16S; Microbiota
PubMed: 37686394
DOI: 10.3390/ijms241713588 -
Monaldi Archives For Chest Disease =... Sep 2023We describe the case of a 61-year-old diabetic man affected by Achromobacter denitrificans. He was immunocompetent and did not have any past history of chronic lung...
We describe the case of a 61-year-old diabetic man affected by Achromobacter denitrificans. He was immunocompetent and did not have any past history of chronic lung disease. The patient was treated with sensitive antibiotic meropenem 1 g three times daily. To our knowledge, only one case of A. denitrificans pneumonia has been reported from the Indian subcontinent, in an individual with underlying lung disease, and none in a healthy person.
PubMed: 37667899
DOI: 10.4081/monaldi.2023.2683