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Scientific Reports Oct 2019Bacteria swim and swarm by rotating the micrometers long, helical filaments of their flagella. They change direction by reversing their flagellar rotation, which...
Bacteria swim and swarm by rotating the micrometers long, helical filaments of their flagella. They change direction by reversing their flagellar rotation, which switches the handedness of the filament's supercoil. So far, all studied functional filaments are composed of a mixture of L- and R-state flagellin monomers. Here we show in a study of the wild type Firmicute Kurthia sp., that curved, functional filaments can adopt a conformation in vivo that is closely related to a uniform, all-L-state. This sheds additional light on transitions of the flagellar supercoil and uniquely reveals the atomic structure of a wild-type flagellar filament in vivo, including six residues showing clearly densities of O-linked glycosylation.
Topics: Anisotropy; Bacterial Proteins; Cryoelectron Microscopy; Firmicutes; Flagella; Flagellin; Fourier Analysis; Glycosylation; Planococcaceae; Software
PubMed: 31628388
DOI: 10.1038/s41598-019-51440-1 -
PloS One 2023Gram-positive, aerobic, motile, rod-shaped, mesophilic epiphytic bacterium Planomicrobium okeanokoites was isolated from the surface of endemic species Himantothallus...
Gram-positive, aerobic, motile, rod-shaped, mesophilic epiphytic bacterium Planomicrobium okeanokoites was isolated from the surface of endemic species Himantothallus grandifolius in Larsemann Hills, Eastern Antarctica. The diversity of epiphytic bacterial communities living on marine algae remains primarily unexplored; virtually no reports from Antarctic seaweeds. The present study used morpho-molecular approaches for the macroalgae and epiphytic bacterium characterization. Phylogenetic analysis was performed using mitochondrial genome encoded COX1 gene; chloroplast genome encodes rbcL; nuclear genome encoded large subunit ribosomal RNA gene (LSU rRNA) for Himantothallus grandifolius and ribosomal encoded 16S rRNA for Planomicrobium okeanokoites. Morphological and molecular data revealed that the isolate is identified as Himantothallus grandifolius, which belongs to Family Desmarestiaceae of Order Desmarestiales in Class Phaeophyceae showing 99.8% similarity to the sequences of Himantothallus grandifolius, from King George Island, Antarctica (HE866853). The isolated bacterial strain was identified on the basis of chemotaxonomic, morpho-phylogenetic, and biochemical assays. A phylogenetic study based on 16S rRNA gene sequences revealed that the epiphytic bacterial strain SLA-357 was closest related to the Planomicrobium okeanokoites showing 98.7% sequence similarity. The study revealed the first report of this species from the Southern Hemisphere to date. Also, there has been no report regarding the association between the Planomicrobium okeanokoites and Himantothallus grandifolius; however, there are some reports on this bacterium isolated from sediments, soils, and lakes from Northern Hemisphere. This study may open a gateway for further research to know about the mode of interactions and how they affect the physiology and metabolism of each other.
Topics: RNA, Ribosomal, 16S; Phylogeny; Planococcaceae; Phaeophyceae; Bacteria; Seaweed; Antarctic Regions; DNA, Bacterial; Fatty Acids; Sequence Analysis, DNA; Bacterial Typing Techniques
PubMed: 37058520
DOI: 10.1371/journal.pone.0282516 -
Bioresource Technology Nov 2021This study aims to construct a high-temperature-resistant microbial consortium to effectively degrade oily food waste by Fed-in-situ biological reduction treatment...
This study aims to construct a high-temperature-resistant microbial consortium to effectively degrade oily food waste by Fed-in-situ biological reduction treatment (FBRT). Oil degrading bacteria were screened under thermophilic conditions of mineral salt medium with increased oil content. The oil degradation and emulsification ability of each stain was evaluated and their synergetic improvement was further confirmed. Consortium of Bacillus tequilensis, Bacillus licheniformis, Bacillus sonorensis and Ureibacillus thermosphaericus was selected and applicated as bacterial agents in FBRT under 55 °C. Changes in pH, moisture, bacterial community and key components of food waste were monitored for 5 days during processing. Facilitated by the bacterial consortium, FBRT gave superior total mass reduction (86.61 ± 0.58% vs. 67.25 ± 1.63%) and non-volatile solids reduction (65.91 ± 1.53% vs. 28.53 ± 2.29%) compared with negative control, the feasibility and efficiency of present FBRT providing a promising in-situ disposal strategy for rapid reduction of oily food waste.
Topics: Bacillus; Biodegradation, Environmental; Food; Microbial Consortia; Planococcaceae; Refuse Disposal; Temperature
PubMed: 34339998
DOI: 10.1016/j.biortech.2021.125635 -
Doklady. Biochemistry and Biophysics Mar 2021Analysis of milk micrbiomes from healthy cows and cows with different (clinical and subclinical) forms of mastitis was performed at two farms of the Central Russia. An...
Analysis of milk micrbiomes from healthy cows and cows with different (clinical and subclinical) forms of mastitis was performed at two farms of the Central Russia. An increase in the operational taxonomic units (OTUs) of bacteria of the phylum Proteоbacteria belonging primarily to Pseudomonadales, Burkholderiales, as well as Streptococcaceae, Staphylococcaceae, and Bacillaceae in the animals with mastitis was detected. The Planococcaceae OTU percentage decreased. The ratio of rarely presented OTUs also changed in the milk of animals with mastitis.
Topics: Animals; Bacteria; Cattle; Female; Mastitis, Bovine; Milk
PubMed: 33895920
DOI: 10.1134/S1607672921020046 -
Bioresource Technology Jul 2020Two bacterial species with the ability to produce biosurfactants were isolated from a pesticide contaminated soil and identified as Planococcus rifietoensis IITR53 and...
Two bacterial species with the ability to produce biosurfactants were isolated from a pesticide contaminated soil and identified as Planococcus rifietoensis IITR53 and Planococcus halotolerans IITR55. Formation of froth indicating the surfactant production was observed when grown in basal salt medium containing 2% glucose. The culture supernatant after 72 h showed reduction in surface tension from 72 N/m to 46 and 42 N/m for strain IITR53 and IITR55 with emulsification index of 51 and 54% respectively. The biosurfactant identified as rhamnolipid based on liquid chromatography-mass spectrometry analysis, was found to inhibit the growth of both gram- positive and negative pathogenic bacteria. Both the rhamnolipids at 40 mg/mL exhibited the release of extracellular DNA and protein content. Also at one third of the MIC, a significant generation of reactive oxygen species was recorded. These rhamnolipids effectively emulsified different vegetable oils suggesting their possible utilization as antimicrobial agent.
Topics: Bacteria; Glycolipids; Planococcus Bacteria; Pseudomonas aeruginosa; Surface-Active Agents
PubMed: 32240926
DOI: 10.1016/j.biortech.2020.123206 -
Dalton Transactions (Cambridge, England... Apr 2016The high activity of urease, a Ni(ii) enzyme, has several adverse effects on human health and agriculture, and its modulation needs the use of inhibitors....
The high activity of urease, a Ni(ii) enzyme, has several adverse effects on human health and agriculture, and its modulation needs the use of inhibitors. 1,4-Benzoquinone (BQ) irreversibly inactivates Sporosarcina pasteurii urease (SPU), with first order kinetics for both the inhibitor and the enzyme. This reaction is stoichiometrically quenched in the presence of sulphite. The 2.07 Å crystal structure of SPU bound to BQ shows the presence of a 1,4-hydroquinone moiety covalently bound to the thiol group of αCys322, a key residue found on the mobile flap regulating the substrate access to the active site. The 1.75 Å crystal structure obtained when sulphite is added to a solution of SPU previously incubated with BQ shows the presence of a 2,5-dihydroxy-benzenesulphonate moiety bound to the αCys322 thiol group. These data reveal how the active site cysteine reacts with a prototypical BQ moiety, found in a large number of natural substances potentially suitable to control the urease activity.
Topics: Benzoquinones; Binding Sites; Crystallography, X-Ray; Molecular Dynamics Simulation; Nickel; Protein Structure, Tertiary; Sporosarcina; Urease
PubMed: 26961812
DOI: 10.1039/c6dt00652c -
Journal of Hazardous Materials Aug 2016Biological precipitation of metallic contaminants has been explored as a remedial technology for contaminated groundwater systems. However, metal toxicity and...
Biological precipitation of metallic contaminants has been explored as a remedial technology for contaminated groundwater systems. However, metal toxicity and availability limit the activity and remedial potential of bacteria. We report the ability of a bacterium, Sporosarcina pasteurii, to remove metals in aerobic aqueous systems through carbonate formation. Its ability to survive and grow in increasingly concentrated aqueous solutions of zinc, cadmium, lead and copper is explored, with and without a metal precipitation mechanism. In the presence of metal ions alone, bacterial growth was inhibited at a range of concentrations depending on the metal. Microbial activity in a urea-amended medium caused carbonate ion generation and pH elevation, providing conditions suitable for calcium carbonate bioprecipitation, and consequent removal of metal ions. Elevation of pH and calcium precipitation are shown to be strongly linked to removal of zinc and cadmium, but only partially linked to removal of lead and copper. The dependence of these effects on interactions between the respective metal and precipitated calcium carbonate are discussed. Finally, it is shown that the bacterium operates at higher metal concentrations in the presence of the urea-amended medium, suggesting that the metal removal mechanism offers a defence against metal toxicity.
Topics: Biodegradation, Environmental; Calcium Carbonate; Carbonates; Chemical Precipitation; Metals, Heavy; Sporosarcina
PubMed: 27136729
DOI: 10.1016/j.jhazmat.2016.04.039 -
Scientific Reports Feb 2020Intestinal flora plays an important role in inflammatory response to systemic or local organs of its host. High calorie diet has been shown to aggravate the condition of...
Intestinal flora plays an important role in inflammatory response to systemic or local organs of its host. High calorie diet has been shown to aggravate the condition of pneumonia and delay recovery, especially in children. However, the underlying mechanisms remain unclear. This study placed SPF rats in a conventional environment, high calorie diet or LPS atomization was performed respectively or combined. Analysis of high-throughput sequencing of intestinal content combined with animal weight, organ index, serum inflammatory factors indicators and bioinformatics found that after pulmonary infection combined with a high-calorie diet, rats showed significant changes such as weight loss and increased lung weight index, and their lung and intestinal tissues showed more obvious inflammatory changes. And its gut flora structure suggests, the abundance of Leuconostocaceae in significantly reduced; abundance of Staphylococcus, Planococcaceae, Staphylococcus, Staphylococcaceae, Bacillales, Gemellales and Aerococcus significant increased. The study showed that high calorie diet and LPS atomization synergistically promoted pneumonia process in rat pups, which is related to changes in structure of intestinal flora. It is worth noting that pneumonia rats fed by convention diet also causing intestinal flora imbalance.
Topics: Animals; Animals, Newborn; Body Weight; Diet; Gastrointestinal Microbiome; High-Throughput Nucleotide Sequencing; Humans; Inflammation; Intestinal Mucosa; Lipopolysaccharides; Lung; Male; Pneumonia; Rats; Rats, Sprague-Dawley
PubMed: 32015367
DOI: 10.1038/s41598-020-58632-0 -
Journal of Applied Microbiology Jun 2015Ureolysis drives microbially induced calcium carbonate precipitation (MICP). MICP models typically employ simplified urea hydrolysis kinetics that do not account for...
AIMS
Ureolysis drives microbially induced calcium carbonate precipitation (MICP). MICP models typically employ simplified urea hydrolysis kinetics that do not account for cell density, pH effect or product inhibition. Here, ureolysis rate studies with whole cells of Sporosarcina pasteurii aimed to determine the relationship between ureolysis rate and concentrations of (i) urea, (ii) cells, (iii) NH4+ and (iv) pH (H(+) activity).
METHODS AND RESULTS
Batch ureolysis rate experiments were performed with suspended cells of S. pasteurii and one parameter was varied in each set of experiments. A Michaelis-Menten model for urea dependence was fitted to the rate data (R(2) = 0·95) using a nonlinear mixed effects statistical model. The resulting half-saturation coefficient, Km , was 305 mmol l(-1) and maximum rate constant, Vmax , was 200 mmol l(-1) h(-1) . However, a first-order model with k1 = 0·35 h(-1) fit the data better (R(2) = 0·99) for urea concentrations up to 330 mmol l(-1) . Cell concentrations in the range tested (1 × 10(7) -2 × 10(8) CFU ml(-1) ) were linearly correlated with ureolysis rate (cell dependent Vmax' = 6·4 × 10(-9) mmol CFU(-1) h(-1) ).
CONCLUSIONS
Neither pH (6-9) nor ammonium concentrations up to 0·19 mol l(-1) had significant effects on the ureolysis rate and are not necessary in kinetic modelling of ureolysis. Thus, we conclude that first-order kinetics with respect to urea and cell concentrations are likely sufficient to describe urea hydrolysis rates at most relevant concentrations.
SIGNIFICANCE AND IMPACT OF THE STUDY
These results can be used in simulations of ureolysis driven processes such as microbially induced mineral precipitation and they verify that under the stated conditions, a simplified first-order rate for ureolysis can be employed. The study shows that the kinetic models developed for enzyme kinetics of urease do not apply to whole cells of S. pasteurii.
Topics: Bacterial Proteins; Calcium Carbonate; Hydrolysis; Kinetics; Sporosarcina; Urea; Urease
PubMed: 25809221
DOI: 10.1111/jam.12804 -
The ISME Journal Jan 2021Enrichment of protective microbiota in the rhizosphere facilitates disease suppression. However, how the disruption of protective rhizobacteria affects disease...
Enrichment of protective microbiota in the rhizosphere facilitates disease suppression. However, how the disruption of protective rhizobacteria affects disease suppression is largely unknown. Here, we analyzed the rhizosphere microbial community of a healthy and diseased tomato plant grown <30-cm apart in a greenhouse at three different locations in South Korea. The abundance of Gram-positive Actinobacteria and Firmicutes phyla was lower in diseased rhizosphere soil (DRS) than in healthy rhizosphere soil (HRS) without changes in the causative Ralstonia solanacearum population. Artificial disruption of Gram-positive bacteria in HRS using 500-μg/mL vancomycin increased bacterial wilt occurrence in tomato. To identify HRS-specific and plant-protective Gram-positive bacteria species, Brevibacterium frigoritolerans HRS1, Bacillus niacini HRS2, Solibacillus silvestris HRS3, and Bacillus luciferensis HRS4 were selected from among 326 heat-stable culturable bacteria isolates. These four strains did not directly antagonize R. solanacearum but activated plant immunity. A synthetic community comprising these four strains displayed greater immune activation against R. solanacearum and extended plant protection by 4 more days in comparison with each individual strain. Overall, our results demonstrate for the first time that dysbiosis of the protective Gram-positive bacterial community in DRS promotes the incidence of disease.
Topics: Actinobacteria; Bacillus; Bacteria; Firmicutes; Incidence; Solanum lycopersicum; Planococcaceae; Plant Diseases; Ralstonia solanacearum; Rhizosphere; Soil Microbiology
PubMed: 33028974
DOI: 10.1038/s41396-020-00785-x