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Environmental Science and Ecotechnology Jul 2023The potential release capacity of arsenic (As) from sediment was evaluated under a high level of exogenous organic matter (EOM) with both bioreactive and chemically...
The potential release capacity of arsenic (As) from sediment was evaluated under a high level of exogenous organic matter (EOM) with both bioreactive and chemically reactive organic matters (OMs). The OMs were characterized by FI, HIX, BIX, and SUVA fluorescence indices showing the biological activities were kept at a high level during the experimental period. At the genus level, Fe/Mn/As-reducing bacteria (, , , and ) and bacteria (, , , and ) that can participate in metabolic transformation using EOM were identified. The reducing condition occurs which promoted As, Fe, and Mn releases at very high concentrations of OM. However, As release increased during the first 15-20 days, followed by a decline contributed by secondary iron precipitation. The degree of As release may be limited by the reactivity of Fe (hydro)oxides. The EOM infiltration enhances As and Mn releases in aqueous conditions causing the risk of groundwater pollution, which could occur in specific sites such as landfills, petrochemical sites, and managed aquifer recharge projects.
PubMed: 36896144
DOI: 10.1016/j.ese.2023.100243 -
Nature Communications Sep 2023The rhizosheath, or the layer of soil closely adhering to roots, can help plants to tolerate drought under moderate soil drying conditions. Rhizosheath formation is the...
The rhizosheath, or the layer of soil closely adhering to roots, can help plants to tolerate drought under moderate soil drying conditions. Rhizosheath formation is the result of poorly understood interactions between root exudates, microbes, and soil conditions. Here, we study the roles played by the soil microbiota in rhizosheath formation in barley (a dry crop). We show that barley rhizosheath formation is greater in acid soil than in alkaline soil, and inoculation with microbiota from acid soil enhances rhizosheath formation in alkaline soil. The rhizosheath-promoting activity is associated with the presence of Flavobacteriaceae and Paenibacillaceae bacteria that express genes for biosynthesis of indole-3-acetic acid (IAA, a common auxin), as determined by metagenomics and metatranscriptomics. Two bacterial strains isolated from rhizosheath (Chryseobacterium culicis and Paenibacillus polymyxa) produce IAA and enhance barley rhizosheath formation, while their IAA-defective mutants are unable to promote rhizosheath formation. Co-inoculation with the IAA-producing strains enhances barley grain yield in field experiments through an increase in spike number. Our findings contribute to our understanding of barley rhizosheath formation, and suggest potential strategies for crop improvement.
Topics: Hordeum; Bacteria; Desiccation; Indoleacetic Acids; Soil
PubMed: 37726263
DOI: 10.1038/s41467-023-40916-4 -
The Lancet. Microbe Aug 2023Paenibacillus thiaminolyticus is a cause of postinfectious hydrocephalus among Ugandan infants. To determine whether Paenibacillus spp is a pathogen in neonatal sepsis,... (Observational Study)
Observational Study
BACKGROUND
Paenibacillus thiaminolyticus is a cause of postinfectious hydrocephalus among Ugandan infants. To determine whether Paenibacillus spp is a pathogen in neonatal sepsis, meningitis, and postinfectious hydrocephalus, we aimed to complete three separate studies of Ugandan infants. The first study was on peripartum prevalence of Paenibacillus in mother-newborn pairs. The second study assessed Paenibacillus in blood and cerebrospinal fluid (CSF) from neonates with sepsis. The third study assessed Paenibacillus in CSF from infants with hydrocephalus.
METHODS
In this observational study, we recruited mother-newborn pairs with and without maternal fever (mother-newborn cohort), neonates (aged ≤28 days) with sepsis (sepsis cohort), and infants (aged ≤90 days) with hydrocephalus with and without a history of neonatal sepsis and meningitis (hydrocephalus cohort) from three hospitals in Uganda between Jan 13, 2016 and Oct 2, 2019. We collected maternal blood, vaginal swabs, and placental samples and the cord from the mother-newborn pairs, and blood and CSF from neonates and infants. Bacterial content of infant CSF was characterised by 16S rDNA sequencing. We analysed all samples using quantitative PCR (qPCR) targeting either the Paenibacillus genus or Paenibacillus thiaminolyticus spp. We collected cranial ultrasound and computed tomography images in the subset of participants represented in more than one cohort.
FINDINGS
No Paenibacillus spp were detected in vaginal, maternal blood, placental, or cord blood specimens from the mother-newborn cohort by qPCR. Paenibacillus spp was detected in 6% (37 of 631 neonates) in the sepsis cohort and, of these, 14% (5 of 37 neonates) developed postinfectious hydrocephalus. Paenibacillus was the most enriched bacterial genera in postinfectious hydrocephalus CSF (91 [44%] of 209 patients) from the hydrocephalus cohort, with 16S showing 94% accuracy when validated by qPCR. Imaging showed progression from Paenibacillus spp-related meningitis to postinfectious hydrocephalus over 1-3 months. Patients with postinfectious hydrocephalus with Paenibacillus spp infections were geographically clustered.
INTERPRETATION
Paenibacillus spp causes neonatal sepsis and meningitis in Uganda and is the dominant cause of subsequent postinfectious hydrocephalus. There was no evidence of transplacental transmission, and geographical evidence was consistent with an environmental source of neonatal infection. Further work is needed to identify routes of infection and optimise treatment of neonatal Paenibacillus spp infection to lessen the burden of morbidity and mortality.
FUNDING
National Institutes of Health and Boston Children's Hospital Office of Faculty Development.
Topics: United States; Infant, Newborn; Child; Humans; Infant; Female; Pregnancy; Uganda; Neonatal Sepsis; Placenta; Paenibacillus; Sepsis; Meningitis; Hydrocephalus; Case-Control Studies
PubMed: 37348522
DOI: 10.1016/S2666-5247(23)00106-4 -
Frontiers in Plant Science 2023species are cosmopolitan soil phytopathogens from the division , which produce mycotoxins and cause significant economic losses of crop plants. However, soils... (Review)
Review
species are cosmopolitan soil phytopathogens from the division , which produce mycotoxins and cause significant economic losses of crop plants. However, soils suppressive to diseases are known to occur, and recent knowledge on microbial diversity in these soils has shed new lights on phytoprotection effects. In this review, we synthesize current knowledge on soils suppressive to diseases and the role of their rhizosphere microbiota in phytoprotection. This is an important issue, as disease does not develop significantly in suppressive soils even though pathogenic and susceptible host plant are present, and weather conditions are suitable for disease. Soils suppressive to diseases are documented in different regions of the world. They contain biocontrol microorganisms, which act by inducing plants' resistance to the pathogen, competing with or inhibiting the pathogen, or parasitizing the pathogen. In particular, some of the , , and species are involved in plant protection from diseases. Besides specific bacterial populations involved in disease suppression, next-generation sequencing and ecological networks have largely contributed to the understanding of microbial communities in soils suppressive or not to diseases, revealing different microbial community patterns and differences for a notable number of taxa, according to the pathosystem, the host plant and the origin of the soil. Agricultural practices can significantly influence soil suppressiveness to diseases by influencing soil microbiota ecology. Research on microbial modes of action and diversity in suppressive soils should help guide the development of effective farming practices for disease management in sustainable agriculture.
PubMed: 38111879
DOI: 10.3389/fpls.2023.1228749 -
Microbial Cell Factories May 2024Biosynthesis of metallic nanoparticles using microorganisms are a fabulous and emerging eco-friendly science with well-defined sizes, shapes and controlled... (Comparative Study)
Comparative Study
BACKGROUND
Biosynthesis of metallic nanoparticles using microorganisms are a fabulous and emerging eco-friendly science with well-defined sizes, shapes and controlled monodispersity. Copper nanoparticles, among other metal particles, have sparked increased attention due to their applications in electronics, optics, catalysis, and antimicrobial agents.
RESULTS
This investigation explains the biosynthesis and characterization of copper nanoparticles from soil strains, Niallia circulans G9 and Paenibacillus sp. S4c by an eco-friendly method. The maximum reduction of copper ions and maximum synthesis CuNPs was provided by these strains. Biogenic formation of CuNPs have been characterized by UV-visible absorption spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray analysis and transmission electron microscopy analysis. Using UV-visible spectrum scanning, the synthesised CuNPs' SPR spectra showed maximum absorption peaks at λ. TEM investigation of the produced CuNPs revealed the development of spherical/hexagonal nanoparticles with a size range of 13-100 nm by the G9 strain and spherical nanoparticles with a size range of 5-40 nm by the S4c strain. Functional groups and chemical composition of CuONPs were also confirmed. The antimicrobial activity of the biosynthesized CuNPs were investigated against some human pathogens. CuNPs produced from the G9 strain had the highest activity against Candida albicans ATCC 10,231 and the lowest against Pseudomonas aeruginosa ATCC 9027. CuNPs from the S4c strain demonstrated the highest activity against Escherichia coli ATCC 10,231 and the lowest activity against Klebsiella pneumonia ATCC 13,883.
CONCLUSION
The present work focused on increasing the CuNPs production by two isolates, Niallia circulans G9 and Paenibacillus sp. S4c, which were then characterized alongside. The used analytics and chemical composition techniques validated the existence of CuONPs in the G9 and S4c biosynthesized nano cupper. CuNPs of S4c are smaller and have a more varied shape than those of G9 strain, according to TEM images. In terms of antibacterial activity, the biosynthesized CuNPs from G9 and S4c were found to be more effective against Candida albicans ATCC 10,231 and E. coli ATCC 10,231, respectively.
Topics: Paenibacillus; Metal Nanoparticles; Copper; Anti-Infective Agents; Microbial Sensitivity Tests; Anti-Bacterial Agents; Ascomycota
PubMed: 38802818
DOI: 10.1186/s12934-024-02422-0 -
BioTechniques May 2024is a rich source of high-value natural components. Endophytic fungi are well studied, yet bacteria research is limited. In this study, endophytic bacteria from were...
is a rich source of high-value natural components. Endophytic fungi are well studied, yet bacteria research is limited. In this study, endophytic bacteria from were isolated using an improved method, showing inhibition of pathogens and growth promotion. JC-3jx, identified as , exhibited significant inhibitory activity against tested fungi and bacteria, including . JC-3jx also promoted corn seed rooting and growth, highlighting its excellent biocontrol and growth-promoting potential.
Topics: Dendrobium; Paenibacillus; Endophytes; Plant Roots; Zea mays
PubMed: 38469872
DOI: 10.2144/btn-2023-0083 -
Annals of Clinical Microbiology and... Nov 2023Globally, surgical site infections (SSI) are the most commonly reported healthcare-associated infections.
BACKGROUND
Globally, surgical site infections (SSI) are the most commonly reported healthcare-associated infections.
METHODS
A multicentre study was conducted among patients who underwent surgical procedures at four hospitals located in Northern (Debre Tabor), Southern (Hawassa), Southwest (Jimma), and Central (Tikur Anbessa) parts of Ethiopia. A total of 752 patients clinically studied for surgical site infection were enrolled. The number of patients from Debre Tabor, Hawassa, Jimma, and Tikur Anbessa, hospitals was 172, 184, 193, and 203, respectively. At each study site, SSI discharge culture was performed from all patients, and positive cultures were characterized by colony characteristics, Gram stain, and conventional biochemical tests. Each bacterial species was confirmed using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI TOF). An antimicrobial susceptibility test (AST) was done on Mueller-Hinton agar using the disk diffusion method. Logistic regression analysis was used to assess associations of dependent and independent variables. A p-value < 0.05 was considered statistically significant. Data were analysed using STATA 16 software.
RESULTS
Among 752 wound discharge cultures performed, 65.5% yielded growth. Among these, 57.9% and 42.1% were Gram-negative and Gram-positive isolates, respectively. In this study, a total of 494 bacteria were isolated; Staphylococcus aureus (31%), Escherichia coli (20.7%), and Klebsiella pneumoniae (9.8%) were the most common. Rare isolates (0.8% each) included Raoultella ornithinolytica, Stenotrophomonas maltophilia, Alcalignes faecalis, Pantoea ecurina, Bacillus flexus, and Paenibacillus tylopili. Enterobacteriaceae showed high levels of resistance to most of the tested antibiotics but lower levels of ertapenem (32.9%), amikacin (24.3%), imipenem (20.3%), and meropenem (17.6%) resistance. Multidrug-resistant (MDR) frequency of Enterobacteriaceae at Debre Tabor, Hawassa, Jimma, and Tikur Anbessa hospitals was 84.5%, 96.5%, 97.3%, and 94%, respectively. Ages ≥ 61 years (AOR = 2.83, 95% CI: 1.02-7.99; P 0.046), prolonged duration of hospital stay (AOR = 4.15, 95% CI: 2.87-6.01; P 0.000), history of previous antibiotics use (AOR = 2.83, 95% CI: 1.06-2.80; P 0.028), history of smoking (AOR = 2.35, 95% CI: 1.44-3.83; P 0.001), emergency surgery (AOR = 2.65, 95% CI: 1.92-3.66; P 0.000), and duration of operation (AOR = 0.27, 95% CI: 0.181-0.392; P 0.000) were significant risk factors.
CONCLUSION
The most prevalent isolates from Gram-positive and Gram-negative bacteria across all hospitals were S. aureus and E. coli, respectively. Many newly emerging Gram-negative and Gram-positive bacteria were identified. Variation between hospitals was found for both SSI etiology type and MDR frequencies. Hence, to prevent the emergence and spread of MDR bacteria, standard bacteriological tests and their AST are indispensable for effective antimicrobial stewardship.
Topics: Humans; Anti-Bacterial Agents; Surgical Wound Infection; Cross-Sectional Studies; Staphylococcus aureus; Escherichia coli; Ethiopia; Prospective Studies; Gram-Negative Bacteria; Gram-Positive Bacteria; Drug Resistance, Bacterial; Microbial Sensitivity Tests; Bacteria; Drug Resistance, Multiple, Bacterial
PubMed: 37936207
DOI: 10.1186/s12941-023-00643-6 -
Microbiome Research Reports 2023American foulbrood (AFB) is a devastating disease of the European honey bee () and is found throughout the world. AFB is caused by the bacterium () Treatment with...
American foulbrood (AFB) is a devastating disease of the European honey bee () and is found throughout the world. AFB is caused by the bacterium () Treatment with antibiotics is strictly forbidden in many regions, including New Zealand. Safe and natural prophylactic solutions to protect honey bees from AFB are needed. Bacteriophages are a well-studied alternative to antibiotics and have been shown to be effective against in other countries. We employed a community science approach to obtaining samples from around New Zealand to discover novel bacteriophages. Standard isolation approaches were employed for both bacteria and bacteriophages. Host range testing was performed by agar overlay spot tests, and cocktail formulation and testing were performed in 96-well plate assays, followed by sub-sampling and CFU visualization on agar plates. Herein, we describe the discovery and isolation of eight bacterial isolates and 26 bacteriophages that are novel and native to New Zealand. The phage genomes were sequenced and annotated, and their genomes were compared to extant sequenced phage genomes. We test the host ranges of the bacteriophages and formulate cocktails to undertake testing on a set of representative bacterial strains. These results form the basis of a promising solution for protecting honey bees in New Zealand from AFB.
PubMed: 38045927
DOI: 10.20517/mrr.2023.16 -
Environmental Science and Pollution... Dec 2023Asphaltenes are the most polar and heavy fraction of petroleum, and their complex structure and toxicity make them resistant to biodegradation. The ability to tolerate...
Asphaltenes are the most polar and heavy fraction of petroleum, and their complex structure and toxicity make them resistant to biodegradation. The ability to tolerate high asphaltene concentrations is crucial to reducing the toxicity-related inhibition of microbial growth and improving their capacity for adaptation, survival, and biodegradation in soils highly contaminated with asphaltenes. This study developed a highly tolerant consortium for efficient asphaltene biodegradation in soils from 22 bacterial isolates obtained from heavy-crude oil-contaminated soils. Isolates corresponded to the Rhodococcus, Bacillus, Stutzerimonas, Cellulosimicrobium, Pseudomonas, and Paenibacillus genera, among others, and used pure asphaltenes and heavy crude oil as the only carbon sources. Surface plate assays were used to evaluate the tolerance of individual isolates to asphaltenes, and the results showed variations in the extension and inhibition rates with maximum tolerance levels at 60,000 mg asphaltenes l. Inhibition assays were used to select non-antagonistic bacterial isolates among those showing the highest tolerance levels to asphaltenes. A consortium made up of the five most tolerant and non-antagonistic bacterial isolates was able to degrade up to 83 wt.% out of 10,000 mg asphaltenes kg in the soil after 52 days. Due to its biological compatibility, high asphaltene tolerance, and ability to utilise it as a source of energy, the degrading consortium developed in this work has shown a high potential for soil bioremediation and is a promising candidate for the treatment of aged soil areas contaminated with heavy and extra-heavy crude oil. This would be the first research to assess and consider extreme bacterial tolerance and microbial antagonism between individual degrading microbes, leading to the development of an improved consortium capable of efficiently degrading high amounts of asphaltenes in soil.
Topics: Biodegradation, Environmental; Soil; Soil Microbiology; Soil Pollutants; Petroleum; Rhodococcus
PubMed: 37982951
DOI: 10.1007/s11356-023-30682-7 -
Antonie Van Leeuwenhoek Sep 2023A Gram-strain positive, aerobic, endospore-forming bacterial strain (JJ-246) was isolated from the rhizosphere of Zea mays. The 16S rRNA gene sequence similarity...
A Gram-strain positive, aerobic, endospore-forming bacterial strain (JJ-246) was isolated from the rhizosphere of Zea mays. The 16S rRNA gene sequence similarity comparisons showed a most closely relationship to Paenibacillus oenotherae DT7-4 (98.4%) and Paenibacillus xanthinolyticus 11N27 (98.0%). The pairwise average nucleotide identity and digital DNA-DNA hybridisation values of the JJ-246 genome assembly against publicly available Paenibacillus type strain genomes were below 82% and 33%, respectively. The draft genome of JJ-246 shared many putative plant-beneficial functions contributing (PBFC) genes, related to plant root colonisation, oxidative stress protection, degradation of aromatic compounds, plant growth-promoting traits, disease resistance, drug and heavy metal resistance, and nutrient acquisition. The quinone system of strain JJ-246, the polar lipid profile and the major fatty acids were congruent with those reported for members of the genus Paenibacillus. JJ-246 was shown to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus plantiphilus sp. nov. is proposed, with JJ-246 (= LMG 32093 = CCM 9089 = CIP 111893) as the type strain.
Topics: Zea mays; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Base Composition; Phylogeny; DNA, Bacterial; Vitamin K 2; Paenibacillus; Fatty Acids; Bacterial Typing Techniques
PubMed: 37338631
DOI: 10.1007/s10482-023-01852-x