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Molecules (Basel, Switzerland) Jul 2020Azole antifungal molecules are broadly used as active ingredients in various products, such as pharmaceuticals and pesticides. This promotes their release into the...
Azole antifungal molecules are broadly used as active ingredients in various products, such as pharmaceuticals and pesticides. This promotes their release into the natural environment. The detailed mechanism of their influence on the biotic components of natural ecosystems remains unexplored. Our research aimed to examine the response of AspCl2.2 to the presence of four azole antifungal agents (clotrimazole, fluconazole, climbazole, epoxiconazole). The experiments performed include analysis of the cell metabolic activity, cell membrane permeability, total glutathione level and activity of glutathione S-transferases. These studies allowed for the evaluation of the cells' oxidative stress response to the presence of azole antifungals. Moreover, changes in the nanomechanical surface properties, including adhesive and elastic features of the cells, were investigated using atomic force microscopy (AFM) and spectrophotometric methods. The results indicate that the azoles promote bacterial oxidative stress. The strongest differences were noted for the cells cultivated with fluconazole. The least toxic effect has been attributed to climbazole. AFM observations unraveled molecular details of bacterial cell texture, structure and surface nanomechanical properties. Antifungals promote the nanoscale modification of the bacterial cell wall. The results presented provided a significant insight into the strategies used by environmental bacterial cells to survive exposures to toxic azole antifungal agents.
Topics: Anti-Bacterial Agents; Azoles; Bacterial Adhesion; Biomechanical Phenomena; Cell Membrane Permeability; Clotrimazole; Epoxy Compounds; Fluconazole; Glutathione; Hydrophobic and Hydrophilic Interactions; Imidazoles; Microbial Sensitivity Tests; Microscopy, Atomic Force; Nanoparticles; Ochrobactrum anthropi; Surface Properties; Triazoles
PubMed: 32717971
DOI: 10.3390/molecules25153348 -
World Journal of Microbiology &... Jun 2020The resistance of microorganisms to heavy metals in polluted environments is mediated by genetically determined mechanisms. One such mechanism includes the intracellular...
The resistance of microorganisms to heavy metals in polluted environments is mediated by genetically determined mechanisms. One such mechanism includes the intracellular sequestration of heavy metals in polyphosphate (polyP) inclusions. In Cr(III) contaminated mediums, Ochrobactrum anthropi DE2010 is able to bind and sequester Cr(III) in polyP inclusions. In order to further study the relationship between Cr(III) tolerance and polyP production in O. anthropi DE2010, we carried out whole genomic sequencing, analysis of single nucleotide polymorphisms (SNPs), polyP chemical quantification, and determination of the relative abundance and morphometry of polyP inclusions. In the O. anthropi DE2010 genome, six polyP and pyrophosphate (PPi) metabolic genes were found. Furthermore, genomic analysis via SNPs calling revealed that O. anthropi ATCC49188 and DE2010 strains had average variations of 1.51% in their whole genome sequences and 1.35% variation associated with the principal polyP metabolic gene cluster. In addition, the accumulation of polyP in the DE2010 strain and number of polyP inclusions found were directly correlated with the concentration of Cr(III) in contaminated cultures. The results presented in this study may enhance the understanding of polyP production in response to Cr(III) toxicity in the O. anthropi DE2010 strain. This knowledge may facilitate the successful removal of Cr(III) from the natural environment.
Topics: Biotechnology; Chromium; Culture Media; Genes, Bacterial; Genome, Bacterial; Genomics; Ochrobactrum anthropi; Polymorphism, Single Nucleotide; Polyphosphates; Sequence Alignment; Stress, Physiological; Whole Genome Sequencing
PubMed: 32588141
DOI: 10.1007/s11274-020-02875-6 -
BMC Research Notes May 2020Di-2-ethylhexyl phthalate (DEHP) pollution is one of the major environmental concerns all over the world. This research aimed at studying the biodegradation kinetics of...
OBJECTIVE
Di-2-ethylhexyl phthalate (DEHP) pollution is one of the major environmental concerns all over the world. This research aimed at studying the biodegradation kinetics of DEHP by a newly isolated bacterial strain. Water and sediment samples were collected from Wuhan South Lake and potent bacterial isolates were screened for DEHP degradation, characterized by biochemical, physiological, morphological and 16S rDNA gene sequencing, and optimized under suitable pH, temperature, NaCl and DEHP concentrations. DEHP and its metabolites were quantified by High Performance Liquid Chromatography and their degradation kinetics were studied.
RESULTS
The newly isolated bacterium was identified as Ochrobactrum anthropi strain L1-W with 99.63% similarity to Ochrobactrum anthropi ATCC 49188. It was capable of utilizing DEHP as the carbon source. The optimum growth temperature, pH, DEHP and NaCl concentration for the strain L1-W were 30 °C, 6, 400 mg/L and 10 g/L respectively. Strain L1-W was capable of degrading almost all (98.7%) of DEHP when the initial concentration was 200 mg/L within a period of 72 h. Besides, it was also found capable of degrading five other phthalates, thus making it a possible candidate for bioremediation of phthalates in the environmental settings.
Topics: Biodegradation, Environmental; China; Chromatography, High Pressure Liquid; Diethylhexyl Phthalate; Humans; Hydrogen-Ion Concentration; Kinetics; Ochrobactrum anthropi; Phylogeny; RNA, Ribosomal, 16S; Soil; Temperature
PubMed: 32448295
DOI: 10.1186/s13104-020-05096-0 -
Genomics Sep 2020Ochrobactrum genus is comprised of soil-dwelling Gram-negative bacteria mainly reported for bioremediation of toxic compounds. Since last few years, mainly two species...
Ochrobactrum genus is comprised of soil-dwelling Gram-negative bacteria mainly reported for bioremediation of toxic compounds. Since last few years, mainly two species of this genus, O. intermedium and O. anthropi were documented for causing infections mostly in the immunocompromised patients. Despite such ubiquitous presence, study of adaptation in various niches is still lacking. Thus, to gain insights into the niche adaptation strategies, pan-genome analysis was carried out by comparing 67 genome sequences belonging to Ochrobactrum species. Pan-genome analysis revealed it is an open pan-genome indicative of the continuously evolving nature of the genus. The presence/absence of gene clusters also illustrated the unique presence of antibiotic efflux transporter genes and type IV secretion system genes in the clinical strains while the genes of solvent resistance and exporter pumps in the environmental strains. A phylogenomic investigation based on 75 core genes depicted better and robust phylogenetic resolution and topology than the 16S rRNA gene. To support the pan-genome analysis, individual genomes were also investigated for the mobile genetic elements (MGE), antibiotic resistance genes (ARG), metal resistance genes (MRG) and virulence factors (VF). The analysis revealed the presence of MGE, ARG, and MRG in all the strains which play an important role in the species evolution which is in agreement with the pan-genome analysis. The average nucleotide identity (ANI) based on the genetic relatedness between the Ochrobactrum species indicated a distinction between individual species. Interestingly, the ANI tool was able to classify the Ochrobactrum genomes to the species level which were assigned till the genus level on the NCBI database.
Topics: Drug Resistance, Bacterial; Environmental Microbiology; Genes, Bacterial; Genome, Bacterial; Genomics; Humans; Interspersed Repetitive Sequences; Molecular Sequence Annotation; Ochrobactrum; Phylogeny; Virulence Factors
PubMed: 32428556
DOI: 10.1016/j.ygeno.2020.04.030 -
Microorganisms Apr 2020Azoxystrobin is one of the most popular strobilurin fungicides, widely used in agricultural fields for decades.Extensive use of azoxystrobin poses a major threat to...
Azoxystrobin is one of the most popular strobilurin fungicides, widely used in agricultural fields for decades.Extensive use of azoxystrobin poses a major threat to ecosystems. However, little is known about the kinetics and mechanism of azoxystrobin biodegradation. The present study reports a newly isolated bacterial strain, SH14, utilizing azoxystrobin as a sole carbon source, was isolated from contaminated soils. Strain SH14 degraded 86.3% of azoxystrobin (50 μg·mL) in a mineral salt medium within five days. Maximum specific degradation rate (), half-saturation constant (), and inhibition constant () were noted as 0.6122 d, 6.8291 μg·mL, and 188.4680 μg·mL, respectively.Conditions for strain SH14 based azoxystrobin degradation were optimized by response surface methodology. Optimum degradation was determined to be 30.2 °C, pH 7.9, and 1.1 × 10 CFU·mL of inoculum. Strain SH14 degraded azoxystrobin via a novel metabolic pathway with the formation of -(4,6-dimethoxypyrimidin-2-yl)-acetamide,2-amino-4-(4-chlorophenyl)-3-cyano-5,6-dimethyl-pyridine, and 3-quinolinecarboxylic acid,6,8-difluoro-4-hydroxy-ethyl ester as the main intermediate products, which were further transformed without any persistent accumulative product. This is the first report of azoxystrobin degradation pathway in a microorganism. Strain SH14 also degraded other strobilurin fungicides, including kresoxim-methyl (89.4%), pyraclostrobin (88.5%), trifloxystrobin (78.7%), picoxystrobin (76.6%), and fluoxastrobin (57.2%) by following first-order kinetic model. Bioaugmentation of azoxystrobin-contaminated soils with strain SH14 remarkably enhanced the degradation of azoxystrobin, and its half-life was substantially reduced by 95.7 and 65.6 days in sterile and non-sterile soils, respectively, in comparison with the controls without strain SH14. The study presents SH14 for enhanced biodegradation of azoxystrobin and elaborates on the metabolic pathways to eliminate its residual toxicity from the environment.
PubMed: 32357564
DOI: 10.3390/microorganisms8050625 -
Revista Espanola de Quimioterapia :... Jun 2020
Topics: Adult; Agricultural Workers' Diseases; Brucella melitensis; Brucellosis; Gram-Negative Bacterial Infections; Humans; Male; Ochrobactrum anthropi; Polymerase Chain Reaction; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 32312029
DOI: 10.37201/req/009.2020 -
Frontiers in Microbiology 2019Deciphering the evolutionary history of pathogenic bacteria and their near neighbors may help to understand the genetic or ecological bases which led to their pathogenic...
Deciphering the evolutionary history of pathogenic bacteria and their near neighbors may help to understand the genetic or ecological bases which led to their pathogenic behavior. The family comprises zoonotic pathogenic species belonging to the genus as well as the environmental genus for which some species are considered as opportunistic pathogens. Here, we used a phylogenomic approach including a set of 145 genomes representative of the family diversity and more than 40 genomes of the order to infer the taxonomic relationships between the family's species. Our results clarified some unresolved phylogenetic ambiguities, conducting to the exclusion of spp. out of the family and the positioning of all spp. as a single genomic species within the current species diversity. Additional analyses also revealed that spp. separate into two clades, one comprising mostly environmental species while the other one includes the species considered as pathogens ( spp.) or opportunistic pathogens (mainly , , and ). Finally, we show that is undergoing a beginning of genome reduction suggestive of an ongoing ecological niche specialization, and that some lineages of and may shift toward an adaption to the human host.
PubMed: 32082266
DOI: 10.3389/fmicb.2019.03083 -
3 Biotech Feb 2020The aim of the study was to examine the influence of single and consortia treatments of drought tolerant rhizobacteria producing ACC deaminase together with additional...
The aim of the study was to examine the influence of single and consortia treatments of drought tolerant rhizobacteria producing ACC deaminase together with additional plant growth promoting (PGP) characteristics on finger millet growth, antioxidant and nutrient concentration under water-stressed and irrigated (no stress) conditions. These rhizobacteria belong to the sp. spp. spp. and sp. The single inoculant of RAA3 () and a consortium inoculant of four bacteria, i.e., DPC9 (), DPB13 (), DPB15 () and DPB16 (), significantly boosted the overall growth parameters and nutrient concentrations in leaves of finger millet. Moreover, elevated levels of the reactive oxygen species scavenging enzymes-superoxide dismutase (17.3%, 11.6%), guaiacol peroxidase (38.7%, 22.2%), catalase (33.7%, 21.3%) and ascorbate peroxidase (18.2%, 10.0%); cellular osmolytes-proline (41.5%, 25.0%), phenol (44.5%, 37.5%); higher leaf chlorophyll (64.4%, 30.8%) and a reduced level of hydrogen peroxide (50.7%, 59.5%) and malondialdehyde (48.4%,72.5%) were noted, respectively, after single inoculation of RAA3 and a consortium treatment by strains DPC9 + DPB13 + DPB15 + DPB16, in contrast with non-treated plants mainly under water-stressed conditions. This finding clearly illustrates that PGPB that express ACC deaminase along with additional PGP traits could be an efficient approach for improving plant health in environments, where agricultural practices are reliant on rain for water.
PubMed: 32030334
DOI: 10.1007/s13205-019-2046-4 -
International Journal of Systematic and... Feb 2020A bacterial strain, designated Sp-1, was isolated from the heterotrich ciliate collected from a reservoir located in Ulsan, Republic of Korea. Cells of Sp-1 were Gram...
A bacterial strain, designated Sp-1, was isolated from the heterotrich ciliate collected from a reservoir located in Ulsan, Republic of Korea. Cells of Sp-1 were Gram stain-negative, rod-shaped, non-spore-forming, non-motile and contained poly-β-hydroxybutyrate granules. Phylogenetic analyses based on 16S rRNA gene sequences indicated that Sp-1 constituted a distinct phylogenetic lineage within different families in the order with a pairwise sequence similarity of 95 % to the species of the genus ATCC 49188 and ESC1 (family ). The major cellular fatty acids were C cyclo ω8 (44.4 %) and C (32.1 %). The identified sole isoprenoid quinone was ubiquinone-10 (Q-10). The major polar lipids produced were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminolipid, two unidentified phospholipids and three unidentified lipids. The genome size was about 5.4 Mbp and the DNA G+C content was 68.2 mol%. Sp-1 exhibited the highest average nucleotide identity value of 76.6 % and DNA-DNA hybridization value of 22.1 % with DSM 19599 (family ). This strain is distinguishable from closely related members of the order by its differential phenotypic, chemotaxonomic, genomic and phylogenetic characteristics. On the basis of evidence from polyphasic taxonomic analysis, we concluded that Sp-1 represents a novel species in a novel genus within the order , for which the name gen. nov., sp. nov. is proposed. The type strain is Sp-1 (=KCTC 62036=JCM 32162). We also describe a novel family, fam. nov., to encompass the proposed novel genus and species.
Topics: Alphaproteobacteria; Bacterial Typing Techniques; Base Composition; Ciliophora; DNA, Bacterial; Fatty Acids; Nucleic Acid Hybridization; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; Republic of Korea; Sequence Analysis, DNA; Ubiquinone
PubMed: 31800387
DOI: 10.1099/ijsem.0.003907 -
International Medical Case Reports... 2019Brucellosis, an important zoonotic disease, is endemic in various parts of the world. Patients diagnosed with brucellosis in developed countries are often travelers and...
Imported Brucellosis In The Era Of Dramatically Increasing Immigrants And Foreign Travelers From Endemic Areas: Occupational Hazards Of Secondary Infection Among Laboratory Technicians In A Nonendemic Country.
BACKGROUND
Brucellosis, an important zoonotic disease, is endemic in various parts of the world. Patients diagnosed with brucellosis in developed countries are often travelers and immigrants from endemic areas. This pathogen is listed as biosafety level 3, which means that it is highly contagious and therefore a risk to clinical laboratory technicians.
CASE PRESENTATION
A 43-year-old Chinese man, who could not understand Japanese, visited our hospital because of an intermittent fever that had persisted for 5 months. Associated symptoms included muscle pain whenever he had a fever. He reported currently working as a welder in Japan. However, his previous employment working in animal husbandry in Heilongjiang, mainland China was not determined at the initial visit owing to language barriers. Two sets of blood culture showed nonfermenting gram-negative bacilli, initially misidentified as and subsequently identified as . Six-week doxycycline and rifampicin were administered, with intravenous gentamicin for the initial 1 week. The patient recovered without relapse, confirmed by the negative result of a agglutination test. The patient's wife and three laboratory technicians were required to undergo blood examinations, which revealed no evidence of infection; however, they received prophylaxis with 3 weeks' doxycycline and rifampicin.
CONCLUSION
In nonendemic countries, immigrants with imported brucellosis can be treated, to prevent secondary brucellosis infection, an occupational hazard among laboratory technicians. Greater attention is needed for positive findings of blood cultures, which may initially be misidentified as . When providing medical care for immigrants with fever of unknown origin, it is especially important for primary care physicians to overcome language barriers so as to assess pertinent information regarding their home country, such as previous employment, to prevent the spread the imported zoonoses in the era of a dramatically increasing number of immigrants and foreign travelers.
PubMed: 31695516
DOI: 10.2147/IMCRJ.S224831