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PloS One 2024Dysbiotic biliary bacterial profile is reported in cancer patients and is associated with survival and comorbidities, raising the question of its effect on the influence...
BACKGROUND
Dysbiotic biliary bacterial profile is reported in cancer patients and is associated with survival and comorbidities, raising the question of its effect on the influence of anticancer drugs and, recently, the suggestion of perichemotherapy antibiotics in pancreatic cancer patients colonized by the Escherichia coli and Klebsiella pneumoniae.
OBJECTIVE
In this study, we investigated the microbial communities that colonize tumours and which bacteria could aid in diagnosing pancreatic and biliary cancer and managing bile-colonized patients.
METHODS
A retrospective study on positive bile cultures of 145 Italian patients who underwent cholangiopancreatography with PC and EPC cancer hospitalized from January 2006 to December 2020 in a QA-certified academic surgical unit were investigated for aerobic/facultative-anaerobic bacteria and fungal organisms.
RESULTS
We found that among Gram-negative bacteria, Escherichia coli and Pseudomonas spp were the most frequent in the EPC group, while Escherichia coli, Klebsiella spp, and Pseudomonas spp were the most frequent in the PC group. Enterococcus spp was the most frequent Gram-positive bacteria in both groups. Comparing the EPC and PC, we found a significant presence of patients with greater age in the PC compared to the EPC group. Regarding Candida spp, we found no significant but greater rate in the PC group compared to the EPC group (11.7% vs 1.96%). We found that Alcaligenes faecalis was the most frequent bacteria in EPC than the PC group, among Gram-negative bacterial species.
CONCLUSIONS
Age differences in gut microbiota composition may affect biliary habitats in our cancer population, especially in patients with pancreatic cancer. Alcaligenes faecalis isolated in the culture of bile samples could represent potential microbial markers for a restricted follow-up to early diagnosis of extra-pancreatic cancer. Finally, the prevalence of Candida spp in pancreatic cancer seems to trigger new aspects about debate about the role of fungal microbiota into their relationship with pancreatic cancer.
Topics: Humans; Bile; Retrospective Studies; Bacteria; Anti-Bacterial Agents; Gram-Negative Bacteria; Biliary Tract Neoplasms; Candida; Escherichia coli; Pancreatic Neoplasms; Microbial Sensitivity Tests
PubMed: 38381746
DOI: 10.1371/journal.pone.0294049 -
International Journal of Molecular... Oct 2020Arylacetonitrilase from ATCC8750 (NitAF) hydrolyzes various arylacetonitriles to the corresponding carboxylic acids. A systematic strategy of amino acid residue...
Arylacetonitrilase from ATCC8750 (NitAF) hydrolyzes various arylacetonitriles to the corresponding carboxylic acids. A systematic strategy of amino acid residue screening through sequence alignment, followed by homology modeling and biochemical confirmation was employed to elucidate the determinant of NitAF catalytic efficiency. Substituting Phe-140 in NitAF (wild-type) to Trp did not change the catalytic efficiency toward phenylacetonitrile, an arylacetonitrile. The mutants with nonpolar aliphatic amino acids (Ala, Gly, Leu, or Val) at location 140 had lower activity, and those with charged amino acids (Asp, Glu, or Arg) exhibited nearly no activity for phenylacetonitrile. Molecular modeling showed that the hydrophobic benzene ring at position 140 supports a mechanism in which the thiol group of Cys-163 carries out a nucleophilic attack on a cyanocarbon of the substrate. Characterization of the role of the Phe-140 residue demonstrated the molecular determinant for the efficient formation of arylcarboxylic acids.
Topics: Acetonitriles; Alcaligenes faecalis; Amino Acid Sequence; Amino Acid Substitution; Aminohydrolases; Bacterial Proteins; Catalytic Domain; Hydrophobic and Hydrophilic Interactions; Models, Molecular; Mutation; Phenylalanine; Protein Conformation
PubMed: 33113984
DOI: 10.3390/ijms21217859 -
Science Advances Jun 2024Heterotrophic nitrifiers continue to be a hiatus in our understanding of the nitrogen cycle. Despite their discovery over 50 years ago, the physiology and environmental...
Heterotrophic nitrifiers continue to be a hiatus in our understanding of the nitrogen cycle. Despite their discovery over 50 years ago, the physiology and environmental role of this enigmatic group remain elusive. The current theory is that heterotrophic nitrifiers are capable of converting ammonia to hydroxylamine, nitrite, nitric oxide, nitrous oxide, and dinitrogen gas via the subsequent actions of nitrification and denitrification. In addition, it was recently suggested that dinitrogen gas may be formed directly from ammonium. Here, we combine complementary high-resolution gas profiles, N isotope labeling studies, and transcriptomics data to show that hydroxylamine is the major product of nitrification in . We demonstrated that denitrification and direct ammonium oxidation to dinitrogen gas did not occur under the conditions tested. Our results indicate that is capable of hydroxylamine production from an organic intermediate. These results fundamentally change our understanding of heterotrophic nitrification and have important implications for its biotechnological application.
Topics: Alcaligenes faecalis; Nitrification; Hydroxylamine; Heterotrophic Processes; Ammonium Compounds; Nitrites; Oxidation-Reduction
PubMed: 38848370
DOI: 10.1126/sciadv.adl3587 -
Acta Naturae 2023Changes in the structure of the N-acyl group in N-acylated amino acid derivatives significantly affect both the recognition and activity of penicillin acylases on this...
Changes in the structure of the N-acyl group in N-acylated amino acid derivatives significantly affect both the recognition and activity of penicillin acylases on this series of substrates. However, penicillin acylases from both Alcaligenes faecalis and Escherichia coli are capable of removing the N-benzyloxycarbonyl protecting group in amino acid derivatives under mild conditions without the use of toxic reagents. Efficiency in using penicillin acylases in preparative organic synthesis can be improved by utilizing modern rational enzyme design methods.
PubMed: 37153508
DOI: 10.32607/actanaturae.13703 -
Microbiology Resource Announcements Jan 2023Whole-genome sequence data for clinically relevant Gram-negative bacteria from the African continent are scarce. In this report, we present the draft genome sequence...
Antibiotic Profiles and Draft Genome Sequences of Kerstersia gyiorum, Providencia stuartii, Providencia vermicola, and Alcaligenes faecalis Strains Recovered from Soft Tissue Biopsy Samples in Ghana.
Whole-genome sequence data for clinically relevant Gram-negative bacteria from the African continent are scarce. In this report, we present the draft genome sequence data and antibiograms of four species, namely, Kerstersia gyiorum, Providencia vermicola, Providencia stuartii, and Alcaligenes faecalis, that were recovered from human soft tissue biopsy samples.
PubMed: 36453948
DOI: 10.1128/mra.00893-22 -
IDCases 2019is a species of gram-negative, rod-shaped, aerobic bacteria commonly found in the environment. -associated nosocomial infections are common in hospitalized patients,...
INTRODUCTION
is a species of gram-negative, rod-shaped, aerobic bacteria commonly found in the environment. -associated nosocomial infections are common in hospitalized patients, but serious life threatening infections are rare. Here, we report a rare case of BSI with resistant to all available antibiotics; successfully treated with double-dose of tigecycline.
PRESENTATION OF CASE
A 60-year-old female presented with bloodstream infection, where the organism was completely resistant to all commercially available antibiotics including polymyxins and tigecycline. The physical condition of the patient was deteriorating and there were no active antibiotics available to prescribe based on sensitivities. Despite the organism's resistance to tigecycline, double-dose of tigecycline therapy (100 mg twice daily, intravenously after a 200 mg single intravenous loading dose) was prescribed intentionally for the treatment of this infection. The organism was completely eradicated from the bloodstream of that patient within the 5 days of therapy-initiation.
DISCUSSION
Double-dose of tigecycline maintains a higher serum drug concentration rather than the standard dose, and in this case, double-dose of tigecycline completely cleared the pandrug-resistant from the blood where initially, that organism was resistant to tigecycline. Previously, were found resistant to fluoroquinolones, but here it was found very rarely resistant to even reserve antibiotics, polymyxins, carbapenems and tigecycline.
CONCLUSION
Pandrug-resistant associated bloodstream infection is a very uncommon case and double-dose of tigecycline may be an effective option to treat it.
PubMed: 31367521
DOI: 10.1016/j.idcr.2019.e00600 -
Vaccines Jul 2020spp. are identified as commensal bacteria and have been found to inhabit Peyer's patches in the gut. We previously reported that -derived lipopolysaccharides (LPS)...
Adjuvant Activity of Synthetic Lipid A of , a Gut-Associated Lymphoid Tissue-Resident Commensal Bacterium, to Augment Antigen-Specific IgG and Th17 Responses in Systemic Vaccine.
spp. are identified as commensal bacteria and have been found to inhabit Peyer's patches in the gut. We previously reported that -derived lipopolysaccharides (LPS) exerted adjuvant activity in systemic vaccination, without excessive inflammation. Lipid A is one of the components responsible for the biological effect of LPS and has previously been applied as an adjuvant. Here, we examined the adjuvant activity and safety of chemically synthesized lipid A. We found that levels of OVA-specific serum IgG antibodies increased in mice that were subcutaneously immunized with ovalbumin (OVA) plus lipid A relative to those that were immunized with OVA alone. In addition, lipid A promoted antigen-specific T helper 17 (Th17) responses in the spleen; upregulated the expression of MHC class II, CD40, CD80, and CD86 on bone marrow-derived dendritic cells (BMDCs); enhanced the production of Th17-inducing cytokines IL-6 and IL-23 from BMDCs. Stimulation with lipid A also induced the production of IL-6 and IL-1β in human peripheral blood mononuclear cells. Moreover, lipid A caused minor side effects, such as lymphopenia and thrombocytopenia. These findings suggest that lipid A is a safe and effective Th17-type adjuvant by directly stimulating dendritic cells in systemic vaccination.
PubMed: 32698404
DOI: 10.3390/vaccines8030395 -
Journal of Nanobiotechnology Aug 2023In recent years, crop production has expanded due to the variety of commercially available species. This increase in production has led to global competition and the...
BACKGROUND
In recent years, crop production has expanded due to the variety of commercially available species. This increase in production has led to global competition and the search for biostimulant products that improve crop quality and yield. At the same time, agricultural products that protect against diseases caused by phytopathogenic microorganisms are needed. Thus, the green synthesis of selenium nanoparticles (SeNPs) is a proposal for achieving these needs. In this research, SeNPs were synthesized from methanolic extract of Amphipterygium glaucum leaves, and chemically and biologically characterized.
RESULTS
The characterization of SeNPs was conducted by ultraviolet-visible spectrophotometry (UV-Vis), scanning electron microscopy (SEM), electron microscopy transmission (TEM), Dynamic Light Scattering (DLS), energy dispersion X-ray spectroscopy (EDX), and infrared spectrophotometry (FTIR) techniques. SeNPs with an average size of 40-60 nm and spherical and needle-shaped morphologies were obtained. The antibacterial activity of SeNPs against Serratia marcescens, Enterobacter cloacae, and Alcaligenes faecalis was evaluated. The results indicate that the methanolic extracts of A. glaucum and SeNPs presented a high antioxidant activity. The biostimulant effect of SeNPs (10, 20, 50, and 100 µM) was evaluated in vinca (Catharanthus roseus), and calendula (Calendula officinalis) plants under greenhouse conditions, and they improved growth parameters such as the height, the fresh and dry weight of roots, stems, and leaves; and the number of flowers of vinca and calendula.
CONCLUSIONS
The antibacterial, antioxidant, and biostimulant properties of SeNPs synthesized from A. glaucum extract demonstrated in this study support their use as a promising tool in crop production.
Topics: Antioxidants; Selenium; Nanoparticles; Anti-Bacterial Agents; Plant Extracts
PubMed: 37537575
DOI: 10.1186/s12951-023-02027-6 -
Scientific Reports Jul 2020Consumption of heavy metals, especially lead (Pb) contaminated food is a serious threat to human health. Higher Pb uptake by the plant affects the quality, growth and...
Consumption of heavy metals, especially lead (Pb) contaminated food is a serious threat to human health. Higher Pb uptake by the plant affects the quality, growth and yield of crops. However, inoculation of plant growth-promoting rhizobacteria (PGPR) along with a mixture of organic amendments and biochar could be an effective way to overcome the problem of Pb toxicity. That's why current pot experiment was conducted to investigate the effect of compost mixed biochar (CB) and ACC deaminase producing PGPR on growth and yield of spinach plants under artificially induced Pb toxicity. Six different treatments i.e., control, Alcaligenes faecalis (PGPR1), Bacillus amyloliquefaciens (PGPR2), compost + biochar (CB), PGPR1 + CB and PGPR2 + CB were applied under 250 mg Pb kg soil. Results showed that inoculation of PGPRs (Alcaligenes faecalis and Bacillus amyloliquefaciens) alone and along with CB significantly enhanced root fresh (47%) and dry weight (31%), potassium concentration (11%) in the spinach plant. Whereas, CB + Bacillus amyloliquefaciens significantly decreased (43%) the concentration of Pb in the spinach root over control. In conclusion, CB + Bacillus amyloliquefaciens has the potential to mitigate the Pb induced toxicity in the spinach. The obtained result can be further used in the planning and execution of rhizobacteria and compost mixed biochar-based soil amendment.
Topics: Alcaligenes faecalis; Bacillus amyloliquefaciens; Bacterial Proteins; Carbon-Carbon Lyases; Charcoal; Chlorophyll; Hydrogen-Ion Concentration; Lead; Plant Roots; Potassium; Soil; Soil Microbiology; Soil Pollutants; Spinacia oleracea; Symbiosis
PubMed: 32699323
DOI: 10.1038/s41598-020-69183-9 -
PloS One 2024Endophytic bacteria, recognized as eco-friendly biofertilizers, have demonstrated the potential to enhance crop growth and yield. While the plant growth-promoting...
Endophytic bacteria, recognized as eco-friendly biofertilizers, have demonstrated the potential to enhance crop growth and yield. While the plant growth-promoting effects of endophytic bacteria have been extensively studied, the impact of weed endophytes remains less explored. In this study, we aimed to isolate endophytic bacteria from native weeds and assess their plant growth-promoting abilities in rice under varying chemical fertilization. The evaluation encompassed measurements of mineral phosphate and potash solubilization, as well as indole-3-acetic acid (IAA) production activity by the selected isolates. Two promising strains, tentatively identified as Alcaligenes faecalis (BTCP01) from Eleusine indica (Goose grass) and Metabacillus indicus (BTDR03) from Cynodon dactylon (Bermuda grass) based on 16S rRNA gene phylogeny, exhibited noteworthy phosphate and potassium solubilization activity, respectively. BTCP01 demonstrated superior phosphate solubilizing activity, while BTDR03 exhibited the highest potassium (K) solubilizing activity. Both isolates synthesized IAA in the presence of L-tryptophan, with the detection of nifH and ipdC genes in their genomes. Application of isolates BTCP01 and BTDR03 through root dipping and spraying at the flowering stage significantly enhanced the agronomic performance of rice variety CV. BRRI dhan29. Notably, combining both strains with 50% of recommended N, P, and K fertilizer doses led to a substantial increase in rice grain yields compared to control plants receiving 100% of recommended doses. Taken together, our results indicate that weed endophytic bacterial strains BTCP01 and BTDR03 hold promise as biofertilizers, potentially reducing the dependency on chemical fertilizers by up to 50%, thereby fostering sustainable rice production.
Topics: Oryza; Endophytes; Alcaligenes faecalis; Plant Weeds; Fertilizers; Phosphates; Indoleacetic Acids; RNA, Ribosomal, 16S; Phylogeny; Plant Roots; Eleusine; Cynodon; Potassium
PubMed: 38753661
DOI: 10.1371/journal.pone.0296547