120,238 results match your criteria bacteria natural

Complex formation of an estrone-salicylaldehyde semicarbazone hybrid with copper(II) and gallium(III): Solution equilibria and biological activity.

J Inorg Biochem 2021 Apr 24;220:111468. Epub 2021 Apr 24.

Department of Inorganic and Analytical Chemistry, Interdisciplinary Excellence Centre, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary; MTA-SZTE Lendület Functional Metal Complexes Research Group, University of Szeged, Dóm tér 7, H-6720 Szeged, Hungary.

The solution chemical properties such as proton dissociation, complex formation with copper(II) and gallium(III) ions in addition to antibacterial and antitumor activity of a novel tridentate salicyaldehyde semicarbazone-estrone hybrid (estrone-SC) and a related bicyclic compound (thn-SC) were investigated. The crystal structure of complex [Cu(thn-SCH)Cl] was studied by single crystal X-ray diffraction method. Estrone-SC and thn-SC form mono-ligand complexes with Cu(II) characterized by relatively high stability, however, they are much less stable than their thiosemicarbazone analogues. Read More

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Broad and potently neutralizing monoclonal antibodies isolated from human survivors of New World hantavirus infection.

Cell Rep 2021 May;35(5):109086

Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232, USA. Electronic address:

New World hantaviruses (NWHs) are endemic in North and South America and cause hantavirus cardiopulmonary syndrome (HCPS), with a case fatality rate of up to 40%. Knowledge of the natural humoral immune response to NWH infection is limited. Here, we describe human monoclonal antibodies (mAbs) isolated from individuals previously infected with Sin Nombre virus (SNV) or Andes virus (ANDV). Read More

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Study of the ultrastructure of Enterococcus faecalis and Streptococcus mutans incubated with salivary antimicrobial peptides.

Clin Exp Dent Res 2021 May 5. Epub 2021 May 5.

Departamento de Microbiología y Parasitología, Facultad de Medicina, Col. Universidad Nacional Autónoma de México, Mexico City, Mexico.

Objectives: Enterococcus faecalis has been associated with root canal infections, while Streptococcus mutans has a central role in the etiology of dental caries. One of the main reasons of endodontic failure has been associated to the presence of E. faecalis and the formation of biofilms. Read More

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Redox-sensitive transcriptional regulator SoxR directly controls antibiotic production, development and thiol-oxidative stress response in Streptomyces avermitilis.

Microb Biotechnol 2021 May 5. Epub 2021 May 5.

State Key Laboratory of Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing, China.

The redox-sensitive transcriptional regulator SoxR is conserved in bacteria. Its role in mediating protective response to various oxidative stresses in Escherichia coli and related enteric bacteria has been well established. However, functions and regulatory mechanisms of SoxR in filamentous Streptomyces, which produce half of known antibiotics, are unclear. Read More

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The impact of aging on innate and adaptive immunity in the human female genital tract.

Aging Cell 2021 May 5:e13361. Epub 2021 May 5.

Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA.

Mucosal tissues in the human female reproductive tract (FRT) are primary sites for both gynecological cancers and infections by a spectrum of sexually transmitted pathogens, including human immunodeficiency virus (HIV), that compromise women's health. While the regulation of innate and adaptive immune protection in the FRT by hormonal cyclic changes across the menstrual cycle and pregnancy are being intensely studied, little to nothing is known about the alterations in mucosal immune protection that occur throughout the FRT as women age following menopause. The immune system in the FRT has two key functions: defense against pathogens and reproduction. Read More

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Dubiofossils from a Mars-analogue subsurface palaeoenvironment: The limits of biogenicity criteria.

Geobiology 2021 May 5. Epub 2021 May 5.

Department of Earth & Planetary Science, University of California, Berkeley, CA, USA.

The search for a fossil record of Earth's deep biosphere, partly motivated by potential analogies with subsurface habitats on Mars, has uncovered numerous assemblages of inorganic microfilaments and tubules inside ancient pores and fractures. Although these enigmatic objects are morphologically similar to mineralized microorganisms (and some contain organic carbon), they also resemble some abiotic structures. Palaeobiologists have responded to this ambiguity by evaluating problematic filaments against checklists of "biogenicity criteria". Read More

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Die-off of plant pathogenic bacteria in tile drainage and anoxic water from a managed aquifer recharge site.

PLoS One 2021 5;16(5):e0250338. Epub 2021 May 5.

Department of Earth Sciences, Environmental Hydrogeology Group, Utrecht University, Utrecht, The Netherlands.

Managed aquifer recharge (MAR) can provide irrigation water and overcome water scarcity in agriculture. Removal of potentially present plant pathogens during MAR is essential to prevent crop diseases. We studied the die-off of three plant pathogenic bacteria in water microcosms with natural or filtered tile drainage water (TDW) at 10 and 25°C and with natural anoxic aquifer water (AW) at 10°C from a MAR site. Read More

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Structural and functional studies of SAV1707 from Staphylococcus aureus elucidate its distinct metal-dependent activity and a crucial residue for catalysis.

Acta Crystallogr D Struct Biol 2021 May 14;77(Pt 5):587-598. Epub 2021 Apr 14.

Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea.

The metallo-β-lactamase fold is the most abundant metal-binding domain found in two major kingdoms: bacteria and archaea. Despite the rapid growth in genomic information, most of these enzymes, which may play critical roles in cellular metabolism, remain uncharacterized in terms of structure and function. In this study, X-ray crystal structures of SAV1707, a hypothetical metalloenzyme from Staphylococcus aureus, and its complex with cAMP are reported at high resolutions of 2. Read More

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Multifunctional graphene-based nanocomposites for simultaneous enhanced photocatalytic degradation and photothermal antibacterial activity by visible light.

Environ Sci Pollut Res Int 2021 May 4. Epub 2021 May 4.

College of International Education, Zhongyuan University of Technology, Zhengzhou, 450007, People's Republic of China.

A new strategy for the wastewater treatment was proposed by combining polyvinylpyrrolidone-functionalized silver nanoparticles with reduced graphene oxide (AgNPs-PVP@rGO) as a visible light-triggered photoactive nanocomposite. The nanocomposite with enhanced photocatalytic degradation and photothermal antibacterial activity can simultaneously decrease the content of organic pollutants and bacteria in the wastewater under visible light irradiation. The efficiency of photocatalytic degradation can be significantly improved by the conjugation of AgNPs onto the rGO surface. Read More

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Hymenobacter negativus sp. nov., bacteria isolated from mountain soil collected in South Korea.

Antonie Van Leeuwenhoek 2021 May 4. Epub 2021 May 4.

Department of Food and Nutrition, Kookmin University, Seoul, 02707, Republic of Korea.

Two novel Gram-negative bacterial strains BT442 and BT584 were isolated from dry soil collected in mountains Busan and Guri, Korea during wintertime. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains BT442 and BT584 both belong to a distinct lineage within the genus Hymenobacter (family Hymenobacteraceae, order Cytophagales, class Cytophagia). Strain BT442 was closely related to Hymenobacter soli PB17 (98. Read More

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Methyl jasmonate and crude extracts of elicit agarwood compounds in shoot culture of Lamk.

Heliyon 2021 Apr 16;7(4):e06725. Epub 2021 Apr 16.

Forest Microbiology Research Group, R & D Centre for Forest, Environment & Forestry Research, Development, and Innovation Agency (FORDA), Ministry of Environment and Forestry, Jalan Gunung Batu 5, Bogor, 16680, Indonesia.

Agarwood forms in the heartwood of trees in the family Thymelaeaceae in response to wounding, infection, or other stresses. Its formation is random and takes decades in natural populations, which are harvested for their aromatic compounds. This harvest has led to declining population, and many agarwood producing trees are considered endangered. Read More

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Antibody-based cancer therapy.

Oncogene 2021 May 4. Epub 2021 May 4.

Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL, USA.

Over the past 25 years, antibody therapeutics have emerged as clinically and commercially successful pharmaceuticals, rapidly approaching 100 Food and Drug Administration approvals with combined annual global sales exceeding $100 billion. Nearly half of the marketed antibody therapeutics are used in oncology. These antibody-based cancer therapies can be broken down into three categories based on their different mechanisms of action, i. Read More

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Dominant egg surface bacteria of Holotrichia oblita (Coleoptera: Scarabaeidae) inhibit the multiplication of Bacillus thuringiensis and Beauveria bassiana.

Sci Rep 2021 May 4;11(1):9499. Epub 2021 May 4.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.

Holotrichia oblita (Coleoptera: Scarabaeidae) and some other scarab beetles are the main soil-dwelling pests in China. Bacillus thuringiensis (Bt) and Beauveria bassiana (Bb) are entomopathogens that have been used as biocontrol agents of various pests. However, scarab larvae especially H. Read More

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Structures of a non-ribosomal peptide synthetase condensation domain suggest the basis of substrate selectivity.

Nat Commun 2021 May 4;12(1):2511. Epub 2021 May 4.

Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.

Non-ribosomal peptide synthetases are important enzymes for the assembly of complex peptide natural products. Within these multi-modular assembly lines, condensation domains perform the central function of chain assembly, typically by forming a peptide bond between two peptidyl carrier protein (PCP)-bound substrates. In this work, we report structural snapshots of a condensation domain in complex with an aminoacyl-PCP acceptor substrate. Read More

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Usnic Acid Treatment Changes the Composition of Mycobacterium tuberculosis Cell Envelope and Alters Bacterial Redox Status.

mSystems 2021 May 4;6(3). Epub 2021 May 4.

Bulgarian Academy of Sciences, The Stephan Angeloff Institute of Microbiology, Laboratory of Metabolomics, Plovdiv, Bulgaria.

developed efficient adaptation mechanisms in response to different environmental conditions. This resulted in the ability to survive in human macrophages and in resistance to numerous antibiotics. To get insight into bacterial responses to potent antimycobacterial natural compounds, we tested how usnic acid, a lichen-derived secondary metabolite, would influence mycobacteria at transcriptomic and metabolomic levels. Read More

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Marine Community Metabolomes Carry Fingerprints of Phytoplankton Community Composition.

mSystems 2021 May 4;6(3). Epub 2021 May 4.

School of Oceanography, University of Washington, Seattle, Washington, USA

Phytoplankton transform inorganic carbon into thousands of biomolecules that represent an important pool of fixed carbon, nitrogen, and sulfur in the surface ocean. Metabolite production differs between phytoplankton, and the flux of these molecules through the microbial food web depends on compound-specific bioavailability to members of a wider microbial community. Yet relatively little is known about the diversity or concentration of metabolites within marine plankton. Read More

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Gut microbiota contributes to the development of endometrial glands in gilts during the ovary-dependent period.

J Anim Sci Biotechnol 2021 May 5;12(1):57. Epub 2021 May 5.

State Key Laboratory of Agricultural Microbiology, College of Animal Sciences and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China.

Background: The hyper-prolificacy Meishan gilts achieved a superior endometrial gland development (EGD) than white crossbred gilts during the ovary-independent period (before 60 d of age). Then, the EGD continues under the management of ovary-derived steroid hormones that regulated by gut microbiota (after 60 d of age). However, whether Meishan gilts' superiority in EGD lasting to the ovary-dependent period (after 60 d of age) and the role of gut microbiota in this period both remain unclear. Read More

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Synergistic action of the gut microbiota in environmental RNA interference in a leaf beetle.

Microbiome 2021 May 4;9(1):98. Epub 2021 May 4.

State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, 430062, China.

Background: RNA interference (RNAi) has emerged as an efficient tool to control insect pests. When insects ingest double-stranded RNAs (dsRNAs) targeted against essential genes, strong gene silencing and mortality can be induced. To exert their function, dsRNA molecules must pass through the insect's gut and enter epithelial cells and/or the hemolymph. Read More

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The Potency of Seaweed Sulfated Polysaccharides for the Correction of Hemostasis Disorders in COVID-19.

Molecules 2021 Apr 29;26(9). Epub 2021 Apr 29.

G.P. Somov Institute of Epidemiology and Microbiology, Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, 690087 Vladivostok, Russia.

Hemostasis disorders play an important role in the pathogenesis, clinical manifestations, and outcome of COVID-19. First of all, the hemostasis system suffers due to a complicated and severe course of COVID-19. A significant number of COVID-19 patients develop signs of hypercoagulability, thrombocytopenia, and hyperfibrinolysis. Read More

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Cardiac Glycosides as Immune System Modulators.

Biomolecules 2021 Apr 29;11(5). Epub 2021 Apr 29.

Department of Biochemistry and Microbiology, University of Chemistry and Technology Prague, Technická 3, 166 28 Prague 6, Czech Republic.

Cardiac glycosides (CGs) are natural steroid compounds occurring both in plants and animals. They are known for long as cardiotonic agents commonly used for various cardiac diseases due to inhibition of Na/K-ATPase (NKA) pumping activity and modulating heart muscle contractility. However, recent studies show that the portfolio of diseases potentially treatable with CGs is much broader. Read More

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Discovery of Siderophore and Metallophore Production in the Aerobic Anoxygenic Phototrophs.

Microorganisms 2021 Apr 29;9(5). Epub 2021 Apr 29.

Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.

Aerobic anoxygenic phototrophs have been isolated from a rich variety of environments including marine ecosystems, freshwater and meromictic lakes, hypersaline springs, and biological soil crusts, all in the hopes of understanding their ecological niche. Over 100 isolates were chosen for this study, representing 44 species from 27 genera. Interactions with Fe and other metal(loid) cations such as Mg, V, Mn, Co, Ni, Cu, Zn, Se and Te were tested using a chromeazurol S assay to detect siderophore or metallophore production, respectively. Read More

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The Peroxiredoxin Asp f3 Acts as Redox Sensor in .

Genes (Basel) 2021 Apr 29;12(5). Epub 2021 Apr 29.

Junior Research Group Evolution of Microbial Interactions, Leibniz-Institute for Natural Product Research and Infection Biology-Hans Knöll Institute (HKI), Beutenbergstr. 11a, 07745 Jena, Germany.

The human pathogenic fungus is readily eradicated by the innate immunity of immunocompetent human hosts, but can cause severe infections, such as invasive aspergillosis (IA), in immunocompromised individuals. During infection, the fungal redox homeostasis can be challenged by reactive oxygen species (ROS), either derived from the oxidative burst of innate immune cells or the action of antifungal drugs. The peroxiredoxin Asp f3 was found to be essential to cause IA in mice, but how Asp f3 integrates with fungal redox homeostasis remains unknown. Read More

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Targeting Bacterial Sortases in Search of Anti-Virulence Therapies with Low Risk of Resistance Development.

Pharmaceuticals (Basel) 2021 Apr 30;14(5). Epub 2021 Apr 30.

Faculty of Pharmacy, "Carol Davila" University of Medicine and Pharmacy, Traian Vuia 6, 020956 Bucharest, Romania.

Increasingly ineffective antibiotics and rapid spread of multi- and pan-resistant bacteria represent a global health threat; hence, the need of developing new antimicrobial medicines. A first step in this direction is identifying new molecular targets, such as virulence factors. Sortase A represents a virulence factor essential for the pathogenesis of Gram-positive pathogens, some of which have a high risk for human health. Read More

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Distribution and Severity of Placental Lesions Caused by the 1B Vaccine Strain in Vaccinated Ewes.

Pathogens 2021 Apr 30;10(5). Epub 2021 Apr 30.

Moredun Research Institute, Edinburgh EH26 0PZ, UK.

infects livestock species worldwide and is the cause of enzootic abortion of ewes (EAE). In Europe, control of the disease is achieved using a live vaccine based on 1B strain. Although the vaccine has been useful for controlling disease outbreaks, abortion events due to the vaccine have been reported. Read More

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Extracts Stimulate IAA Biosynthesis in ZZ21 via the Indole-3-pyruvic Acid Pathway.

Microorganisms 2021 Apr 30;9(5). Epub 2021 Apr 30.

College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.

Inter-organismal metabolites play important roles in regulating organism behavior and the communication between organisms. Nematodes, the most abundant animals on earth, are crucial participants in soil ecosystems through their interactions with microbes. For example, bacterial-feeding nematodes increase the activity of indole-3-acetic acid (IAA)-producing bacteria and the IAA content in soil. Read More

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Macrophage Proteome Analysis at Different Stages of Subspecies Infection Reveals a Mechanism of Pathogen Dissemination.

Proteomes 2021 Apr 30;9(2). Epub 2021 Apr 30.

Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA.

Johne's disease is a chronic and usually fatal enteric infection of ruminants caused by subspecies (MAP) and is responsible for hundreds of millions of dollars in losses for the agricultural industry. Natural infection typically begins with bacterial uptake and translocation through the epithelium of the small intestine, followed by ingestion by tissue macrophages and dissemination via the lymphatic or blood system throughout the body. To gain insights into the host responses and adaptation of MAP within phagocytic cells, we utilized the previously developed cell culture passage model, and mass spectrometric-based quantitative proteomic approach. Read More

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The role of conductive nanoparticles in anaerobic digestion: Mechanism, current status and future perspectives.

Chemosphere 2021 Apr 27;280:130601. Epub 2021 Apr 27.

Department of Environmental Science, SRM University-AP, Amaravati, Andhra Pradesh, 522502, India. Electronic address:

In the current scenario, alternative energy sources are the need of the hour. Organic wastes having a larger fraction of biodegradable constituents present a sustainable bioenergy source. It has been reported that the calorific value of biogas generated by anaerobic digestion (AD) is 21-25 MJ/m with the treatment which makes it an excellent replacement of natural gas and fossil fuels and can reduce more than 80% greenhouse gas emission to the surroundings. Read More

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Small molecule natural products in human nasal/oral microbiota.

J Ind Microbiol Biotechnol 2021 Feb 6. Epub 2021 Feb 6.

Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley 94720, USA.

Small molecule natural products are a chemically diverse class of biomolecules that fulfill myriad biological functions, including autoregulation, communication with microbial neighbors and the host, interference competition, nutrient acquisition, and resistance to oxidative stress. Human commensal bacteria are increasingly recognized as a potential source of new natural products, which may provide insight into the molecular ecology of many different human body sites as well as novel scaffolds for therapeutic development. Here, we review the scientific literature on natural products derived from residents of the human nasal/oral cavity, discuss their discovery, biosynthesis, and ecological roles, and identify key questions in the study of these compounds. Read More

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February 2021

Structural Basis for the Interactions of the Colibactin Resistance Gene Product ClbS with DNA.

Biochemistry 2021 May 4. Epub 2021 May 4.

Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States.

The natural product colibactin, along with its associated biosynthetic gene cluster, is an example system for the role microbially derived small molecules play in the human microbiome. This is particularly relevant in the human gut, where host microbiota is involved in various disorders, including colorectal cancer pathogenesis. Bacteria harboring the colibactin gene cluster induce alkylation of nucleobases in host DNA, forming interstrand cross-links both and . Read More

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Flexible integrated sensing platform for monitoring wound temperature and predicting infection.

Microb Biotechnol 2021 May 4. Epub 2021 May 4.

Department of Burn and Plastic Surgery, Second Affiliated Hospital of Air Force Military Medical University, Xi'an, 710000, China.

Wound infection is a challenging clinical problem that imposes substantial economic and psychological burdens on patients. However, the wound covered by a dressing is in an 'unknown' state. Recently, researchers have focused on understanding the condition of the wound without removing the dressing. Read More

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