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Computational Intelligence and... 2022The focus of this research is to isolating and identifying bacteria that produce calcite precipitate, as well as determining whether or not these bacteria are suitable...
The focus of this research is to isolating and identifying bacteria that produce calcite precipitate, as well as determining whether or not these bacteria are suitable for incorporation into concrete in order to enhance the material's strength and make the environment protection better. In order to survive the high "potential of hydrogen" of concrete, microbes that are going to be added to concrete need to be able to withstand alkali, and they also need to be able to develop endospores so that they can survive the mechanical forces that are going to be put on the concrete while it is being mixed. In order to precipitate CaCO in the form of calcite, they need to have a strong urease activity. Both Bacillus sphaericus and the Streptococcus aureus bacterial strains were evaluated for their ability to precipitate calcium carbonate (CaCO). These strains were obtained from the Department of Biotechnology at GLA University in Mathura. This research aims to solve the issue of augmenting the tension and compression strengths of concrete by investigating possible solutions for environmentally friendly concrete. The sterile cultures of the microorganisms were mixed with water, which was one of the components of the concrete mixture, along with the nutrients in the appropriate proportions. After that, the blocks were molded, and then pond-cured for 7, 28, 56, 90, 120, 180, 270, and 365 days, respectively, before being evaluated for compressibility and tensile strength. An investigation into the effect that bacteria have on compression strength was carried out, and the outcomes of the tests showed that bacterial concrete specimens exhibited an increase in mechanical strength. When compared to regular concrete, the results showed a maximum increase of 16 percent in compressive strength and a maximum increase of 12 percent in split tensile strength. This study also found that both bacterial concrete containing 106, 107, and 108 cfu/ml concentrations made from Bacillus sphaericus and Streptococcus aureus bacteria gave better results than normal concrete. Both cluster analysis (CA) and regression analysis (RA) were utilized in this research project in order to measure and analyze mechanical strength.
Topics: Bacillaceae; Bacteria; Calcium Carbonate; Construction Materials; Humans; Regression Analysis
PubMed: 36093479
DOI: 10.1155/2022/4411876 -
Scientific Reports Jan 2023Aromatic compounds and metalloid oxyanions are abundant in the environment due to natural resources and industrial wastes. The high toxicity of phenol and tellurite...
Aromatic compounds and metalloid oxyanions are abundant in the environment due to natural resources and industrial wastes. The high toxicity of phenol and tellurite poses a significant threat to all forms of life. A halotolerant bacterium was isolated and identified as Lysinibacillus sp. EBL303. The remediation analysis shows that 500 mg/L phenol and 0.5 mM tellurite can be remediated entirely in separate cultures within 74 and 56 h, respectively. In addition, co-remediation of pollutants resulted in the same phenol degradation and 27% less tellurite reduction within 98 h. Since phenol and tellurite exhibited inhibitory behavior, their removal kinetics fitted well with the first-order model. In the characterization of biosynthesized tellurium nanoparticles (TeNPs), transmission electron microscopy, dynamic light scattering, FE-SEM, and dispersive X-ray (EDX) showed that the separated intracellular TeNPs were spherical and consisted of only tellurium with 22-148 nm in size. Additionally, investigations using X-ray diffraction and Fourier-transform infrared spectroscopy revealed proteins and lipids covering the surface of these amorphous TeNPs. Remarkably, this study is the first report to demonstrate the simultaneous bioremediation of phenol and tellurite and the biosynthesis of TeNPs, indicating the potential of Lysinibacillus sp. EBL303 in this matter, which can be applied to environmental remediation and the nanotechnology industry.
Topics: Tellurium; Biodegradation, Environmental; Phenol; Nanoparticles; Bacillaceae; Phenols
PubMed: 36690691
DOI: 10.1038/s41598-023-28468-5 -
Applied and Environmental Microbiology Sep 2022Microbial-induced calcite precipitation is a promising technology to solve the problem of cracks in soil concrete. The most intensively investigated microorganisms are...
Microbial-induced calcite precipitation is a promising technology to solve the problem of cracks in soil concrete. The most intensively investigated microorganisms are urease-producing bacteria. Lysinibacillus that is used as urease-producing bacteria in concrete repair has rarely been reported. In this study, Lysinibacillus boronitolerans with a high urease activity was isolated from soil samples. This strain is salt- and alkali-tolerance, and at pH 13, can grow to ~OD 2.0 after 24 h. At a salt concentration of 6%, the strain can still grow to ~OD 1.0 after 24 h. The feasibility of using this strain in self-healing concrete was explored. The data showed that cracks within ~0.6 mm could be repaired naturally with hydration when spores and substrates were added to the concrete in an appropriate proportion. Moreover, the number and morphology of CaCO crystals that were produced by bacteria can be influenced by the concrete environment. An efficiency method to elucidate the process of microbial-induced calcium carbonate crystal formation was established with Particle Track G400. This study provides a template for future studies on the theory of mineralization based on microorganisms. The formation of calcium carbonate crystals in concrete by urease-producing bacteria is not understood fully. In this study, a Lysinibacillus boronitolerans strain with a high urease activity was isolated and used to analyze the counts and sizes of the crystals and the relationship with time. The data showed that the number of crystal particles increases exponentially in a short period with sufficient substrate, after which the crystals grow, precipitate or break. In concrete, the rate-limiting steps of calcium carbonate crystal accumulation are spore germination and urease production. These results provided data support for the rational design of urease-producing bacteria in concrete repair.
Topics: Alkalies; Bacillaceae; Bacteria; Calcium Carbonate; Construction Materials; Soil; Urease
PubMed: 36036598
DOI: 10.1128/aem.00804-22 -
Applied and Environmental Microbiology Apr 2019Permafrost hosts a community of microorganisms that survive and reproduce for millennia despite extreme environmental conditions, such as water stress, subzero...
Permafrost hosts a community of microorganisms that survive and reproduce for millennia despite extreme environmental conditions, such as water stress, subzero temperatures, high salinity, and low nutrient availability. Many studies focused on permafrost microbial community composition use DNA-based methods, such as metagenomics and 16S rRNA gene sequencing. However, these methods do not distinguish among active, dead, and dormant cells. This is of particular concern in ancient permafrost, where constant subzero temperatures preserve DNA from dead organisms and dormancy may be a common survival strategy. To circumvent this, we applied (i) LIVE/DEAD differential staining coupled with microscopy, (ii) endospore enrichment, and (iii) selective depletion of DNA from dead cells to permafrost microbial communities across a Pleistocene permafrost chronosequence (19,000, 27,000, and 33,000 years old). Cell counts and analysis of 16S rRNA gene amplicons from live, dead, and dormant cells revealed how communities differ between these pools, how they are influenced by soil physicochemical properties, and whether they change over geologic time. We found evidence that cells capable of forming endospores are not necessarily dormant and that members of the class were more likely to form endospores in response to long-term stressors associated with permafrost environmental conditions than members of the , which were more likely to persist as vegetative cells in our older samples. We also found that removing exogenous "relic" DNA preserved within permafrost did not significantly alter microbial community composition. These results link the live, dead, and dormant microbial communities to physicochemical characteristics and provide insights into the survival of microbial communities in ancient permafrost. Permafrost soils store more than half of Earth's soil carbon despite covering ∼15% of the land area (C. Tarnocai et al., Global Biogeochem Cycles 23:GB2023, 2009, https://doi.org/10.1029/2008GB003327). This permafrost carbon is rapidly degraded following a thaw (E. A. G. Schuur et al., Nature 520:171-179, 2015, https://doi.org/10.1038/nature14338). Understanding microbial communities in permafrost will contribute to the knowledge base necessary to understand the rates and forms of permafrost C and N cycling postthaw. Permafrost is also an analog for frozen extraterrestrial environments, and evidence of viable organisms in ancient permafrost is of interest to those searching for potential life on distant worlds. If we can identify strategies microbial communities utilize to survive in permafrost, it may yield insights into how life (if it exists) survives in frozen environments outside of Earth. Our work is significant because it contributes to an understanding of how microbial life adapts and survives in the extreme environmental conditions in permafrost terrains.
Topics: Actinobacteria; Alaska; Bacillaceae; Carbon; Clostridiaceae; DNA, Bacterial; Ecology; Freezing; Metagenomics; Microbiota; Permafrost; Phylogeny; RNA, Ribosomal, 16S; Soil; Soil Microbiology; Spores, Bacterial; Temperature
PubMed: 30683748
DOI: 10.1128/AEM.02646-18 -
FEBS Letters Feb 2021Glucuronoxylans represent a significant fraction of woody biomass, and its decomposition is complicated by the presence of lignin-carbohydrate complexes (LCCs). Herein,...
Glucuronoxylans represent a significant fraction of woody biomass, and its decomposition is complicated by the presence of lignin-carbohydrate complexes (LCCs). Herein, LCCs from birchwood were used to investigate the potential coordinated action of a glucuronoyl esterase (TtCE15A) and two α-glucuronidases (SdeAgu115A and AxyAgu115A). When supplementing α-glucuronidase with equimolar quantities of TtCE15A, total MeGlcpA released after 72 h by SdeAgu115A and AxyAgu115A increased from 52% to 67%, and 61% to 95%, respectively. Based on the combined TtCE15A and AxyAgu115A activities, ~ 34% of MeGlcpA in the extracted birchwood glucuronoxylan was occupied as LCCs. Notably, insoluble LCC fractions reduced soluble α-glucuronidase concentrations by up to 70%, whereas reduction in soluble TtCE15A was less than 30%, indicating different tendencies to adsorb onto the LCC substrate.
Topics: Bacillaceae; Bacterial Proteins; Betula; Biomass; Enzyme Assays; Esterases; Gammaproteobacteria; Gene Expression; Glucuronic Acid; Glycoside Hydrolases; Hydrolysis; Kinetics; Lignin; Polysaccharides; Recombinant Proteins; Wood; Xylans
PubMed: 33277689
DOI: 10.1002/1873-3468.14019 -
Scientific Reports Aug 2016In the soil environment, Bacilli can affect nematode development, fecundity and survival. However, although many Bacillus species can kill nematodes, the virulence...
In the soil environment, Bacilli can affect nematode development, fecundity and survival. However, although many Bacillus species can kill nematodes, the virulence mechanisms Bacilli utilize remain unknown. In this study, we collected 120 strains comprising 30 species across the Bacillaceae and Paenibacillaceae families of the Bacillales order and measured their nematicidal activities in vitro. Comparison of these strains' nematicidal capacities revealed that nine species, including Bacillus thuringiensis, B. cereus, B. subtilis, B. pumilus, B. firmus, B. toyonensis, Lysinibacillus sphaericus, Brevibacillus laterosporus and B. brevis, were highly nematicidal, the first of which showed the highest activity. Genome sequencing and analysis identified many potential virulence factors, which grouped into five types. At least four possible mechanisms were deduced on the basis of the combination of these factors and the bacterial nematicidal activity, including a pore-forming mechanism of crystal proteins, an inhibition-like mechanism of thuringiensin and a degradation mechanism of proteases and/or chitinases. Our results demonstrate that 120 spore-forming Bacilli across different families share virulence factors that may contribute to their nematicidal capacity.
Topics: Animals; Bacillaceae; Bacterial Proteins; DNA, Bacterial; Nematoda; Paenibacillus; Phylogeny; Sequence Analysis, DNA; Soil Microbiology; Virulence Factors
PubMed: 27539267
DOI: 10.1038/srep31341 -
Journal of Insect Science (Online) Mar 2023Hyphantria cunea Drury (Lepidoptera: Erebidae) is a quarantine pest in China that can cause damage to hundreds of plants. As biological control agents, Nuclear...
Hyphantria cunea Drury (Lepidoptera: Erebidae) is a quarantine pest in China that can cause damage to hundreds of plants. As biological control agents, Nuclear Polyhedrosis Virus (NPV) and Bacillus thuringiensis Berliner (Bacillales: Bacillaceae) (Bt) are commonly used to inhibit the prevalence of H. cunea. To investigate the role of midgut bacteria in the infection of NPV and Bt in H. cunea, we performed a series of tests, including isolating the dominant culturable bacteria in the midgut, eliminating intestinal bacteria, and respectively inoculating the dominant strains with NPV and Bt for bioassay. Two dominant bacteria, Klebsiella oxytoca Lautrop (Enterobacterales: Enterobacteriaceae) and Enterococcus mundtii Collins (Lactobacillales: Enterococcaceae), in the midgut of H. cunea were identified, and a strain of H. cunea larvae without intestinal bacteria was successfully established. In the bioassays of entomopathogen infection, K. oxytoca showed significant synergistic effects with both NPV and Bt on the death of H. cunea. In contrast, E. mundtii played antagonistic effects. This phenomenon may be attributed to the differences in the physico-chemical properties of the two gut bacteria and the alkaline environment required for NPV and Bt to infect the host. It is worth noting that the enhanced insecticidal activity of K. oxytoca on NPV and Bt provides a reference for future biological control of H. cunea by intestinal bacteria.
Topics: Animals; Lepidoptera; Bacillus thuringiensis; Bacillaceae; Nucleopolyhedroviruses; Bacillales; Moths; Larva
PubMed: 36916277
DOI: 10.1093/jisesa/iead009 -
International Journal of Environmental... Dec 2022In recent years, PBAT (polybutylene adipate-co-terephthalate) mulch has become one of the most commonly used biodegradable mulching films. In this paper, five potential...
In recent years, PBAT (polybutylene adipate-co-terephthalate) mulch has become one of the most commonly used biodegradable mulching films. In this paper, five potential strains of PBAT film degrading bacteria were screened from the soil sample using PBAT film as the sole carbon source. A highly efficient PBAT degrading strain JZ1 was isolated by comparing the degradation performance of PBAT mulching film identified as S2313 by 16S rDNA sequence analysis. The capacity of the strain to degrade PBAT film was optimized by adjusting the cultivation conditions such as nitrogen source, pH, and inoculum volume. After 8 weeks of cultivation, the actual degradation rate of the strain to PBAT mulch film reached 12.45%. SEM (scanning electron microscopy) coupled with EDX (energy dispersive spectroscopy) analysis showed that microbial degradation is an oxidation process and is mainly due to the amorphous regions of the PBAT film. The biodegradation of PBAT film by may provide a promising method for regulating the degradation progress of PBAT film in the farmlands.
Topics: Polyesters; Microscopy, Electron, Scanning; Motion Pictures; Bacteria; Farms; Biodegradation, Environmental; Bacillaceae
PubMed: 36554967
DOI: 10.3390/ijerph192417087 -
Journal of Applied Microbiology Jan 2017To determine the responses of spores of Bacillus subtilis and Bacillus anthracis surrogate Bacillus thuringiensis Al Hakam to I treatment.
AIMS
To determine the responses of spores of Bacillus subtilis and Bacillus anthracis surrogate Bacillus thuringiensis Al Hakam to I treatment.
METHODS AND RESULTS
Spores of B. subtilis and B. thuringiensis killed by aqueous 30°C-I could germinate, and their inner membrane (IM) was intact. Spore coats were important in I resistance, DNA-protective proteins were not important, and survivors of I treatment were not mutagenized. Viabilities of I -treated, 90-98% killed spores were much lower on high-salinity media, and the treated spores were more heat sensitive than the untreated spores. Germinated I -killed spores were dead as determined by staining with nucleic acid dyes, and many appeared to have been lysed.
CONCLUSIONS
Aqueous I appeared to kill B. subtilis and B. thuringiensis spores such that spores lyse soon after they germinate, and not by causing DNA damage or rupture of spores' IM. I treatment also generated many damaged spores that could only be recovered under nonstressful conditions.
SIGNIFICANCE AND IMPACT OF THE STUDY
This work shows that spores of the model organism B. subtilis, and B. thuringiensis, a surrogate for B. anthracis spores, exhibit similar mechanisms of resistance to and killing by I . Generation by I treatment of conditionally dead spores indicates that appropriate media are essential to efficiently enumerate viable I -treated spores.
Topics: Bacillus; Bacillus anthracis; Bacillus subtilis; DNA Damage; Hot Temperature; Iodine; Spores, Bacterial
PubMed: 27696602
DOI: 10.1111/jam.13310 -
BMC Microbiology Mar 2023Thermostable microorganisms are extremophiles. They have a special genetic background and metabolic pathway and can produce a variety of enzymes and other active...
BACKGROUND
Thermostable microorganisms are extremophiles. They have a special genetic background and metabolic pathway and can produce a variety of enzymes and other active substances with special functions. Most thermo-tolerant microorganisms from environmental samples have resisted cultivation on artificial growth media. Therefore, it is of great significance to isolate more thermo-tolerant microorganisms and study their characteristics to explore the origin of life and exploit more thermo-tolerant enzymes. Tengchong hot spring in Yunnan contains a lot of thermo-tolerant microbial resources because of its perennial high temperature. The ichip method was developed by D. Nichols in 2010 and can be used to isolate so-called "uncultivable" microorganisms from different environments. Here, we describe the first application of modified ichip to isolate thermo-tolerant bacteria from hot springs.
RESULTS
In this study, 133 strains of bacteria belonging to 19 genera were obtained. 107 strains of bacteria in 17 genera were isolated by modified ichip, and 26 strains of bacteria in 6 genera were isolated by direct plating methods. 25 strains are previously uncultured, 20 of which can only be cultivated after being domesticated by ichip. Two strains of previously unculturable Lysobacter sp., which can withstand 85 °C, were isolated for the first time. Alkalihalobacillus, Lysobacter and Agromyces genera were first found to have 85 °C tolerance.
CONCLUSION
Our results indicate that the modified ichip approach can be successfully applied in a hot spring environment.
Topics: Hot Springs; China; Actinomycetales; Bacillaceae; Culture Media
PubMed: 36869305
DOI: 10.1186/s12866-023-02803-2