Cellular and molecular mechanisms of antimony transport, toxicity and resistance

2016 ◽  
Vol 13 (6) ◽  
pp. 955 ◽  
Author(s):  
Markus J. Tamás
Keyword(s):  
Environmental Exposure ◽  
Molecular Mechanisms ◽  
Biological Properties ◽  
Industrial Applications ◽  
Modern Technology ◽  
Wide Range ◽  
Technology Applications ◽  
Toxic Metalloid ◽  
High Concentrations ◽  
In Cells

Environmental contextAntimony is a toxic metalloid that is used in a wide range of modern technology applications and in medical treatments. The accelerating needs for antimony in various industrial applications has led to concerns about increased human and environmental exposure. This review provides a brief summary of the biological properties of antimony and its mechanisms of actions in cells. AbstractAntimony is a toxic metalloid that is naturally present in low amounts in the environment, but can locally reach high concentrations at mining and processing sites. Today, antimony is used in a wide range of modern technology applications and is also an important constituent of pharmacological drugs. The increasing use of antimony has led to concerns about human and environmental exposure. Yet little is known about the biological properties of antimony and its mechanisms of actions in cells. This review will provide a brief summary of how antimony enters and affects cells, and how cells deal with the presence of this metalloid to acquire resistance.

scholarly journals Secondary metabolites of a marine-derived Penicillium ochrochloron

2021 ◽  
Vol 13 (3) ◽  
pp. 11020
Author(s):  
Peter M. EZE ◽  
Ying GAO ◽  
Yang LIU ◽  
Lasse Van GEELEN ◽  
Chika P. EJIKEUGWU ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Secondary Metabolites ◽  
Biological Properties ◽  
Industrial Applications ◽  
Biologically Active ◽  
Fungal Isolation ◽  
The North ◽  
Wide Range ◽  
Extremophilic Fungi ◽  
Fungal Secondary Metabolites

Extremophilic fungi have received considerable attention recently as new promising sources of biologically active compounds with potential pharmaceutical applications. This study investigated the secondary metabolites of a marine-derived Penicillium ochrochloron isolated from underwater sea sand collected from the North Sea in St. Peter-Ording, Germany. Standard techniques were used for fungal isolation, taxonomic identification, fermentation, extraction, and isolation of fungal secondary metabolites. Chromatographic separation and spectroscopic analyses of the fungal secondary metabolites yielded eight compounds: talumarin A (1), aspergillumarin A (2), andrastin A (3), clavatol (4), 3-acetylphenol (5), methyl 2,5-dihydro-4-hydroxy-5-oxo-3-phenyl-2-furanpropanoate (6), emodin (7) and 2-chloroemodin (8). After co-cultivation with Bacillus subtilis, the fungus was induced to express (-)-striatisporolide A (9). Compound 1 was evaluated for antibacterial activity against Staphylococcus aureus, Acinetobacter baumannii, Mycobacterium smegmatis, and M. tuberculosis, as well as cytotoxicity against THP-1 cells. The compound, however, was not cytotoxic to THP-1 cells and had no antibacterial activity against the microorganisms tested. The compounds isolated from P. ochrochloron in this study are well-known compounds with a wide range of beneficial biological properties that can be explored for pharmaceutical, agricultural, or industrial applications. This study highlights the bioprospecting potential of marine fungi and confirms co-cultivation as a useful strategy for the discovery of new natural products.

scholarly journals Pleiotropic Biological Effects of Dietary Phenolic Compounds and their Metabolites on Energy Metabolism, Inflammation and Aging

Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 596 ◽  
Author(s):  
María del Carmen Villegas-Aguilar ◽  
Álvaro Fernández-Ochoa ◽  
María de la Luz Cádiz-Gurrea ◽  
Sandra Pimentel-Moral ◽  
Jesús Lozano-Sánchez ◽  
...  
Keyword(s):  
Energy Metabolism ◽  
Phenolic Compounds ◽  
Molecular Mechanisms ◽  
Biological Effects ◽  
Biological Properties ◽  
In Vivo Studies ◽  
Wide Range ◽  
High Prevalence

Dietary phenolic compounds are considered as bioactive compounds that have effects in different chronic disorders related to oxidative stress, inflammation process, or aging. These compounds, coming from a wide range of natural sources, have shown a pleiotropic behavior on key proteins that act as regulators. In this sense, this review aims to compile information on the effect exerted by the phenolic compounds and their metabolites on the main metabolic pathways involved in energy metabolism, inflammatory response, aging and their relationship with the biological properties reported in high prevalence chronic diseases. Numerous in vitro and in vivo studies have demonstrated their pleiotropic molecular mechanisms of action and these findings raise the possibility that phenolic compounds have a wide variety of roles in different targets.

scholarly journals Is the commonly used UV filter benzophenone-3 a risk factor for the nervous system?

2021 ◽  
Author(s):  
Agnieszka Wnuk ◽  
Małgorzata Kajta
Keyword(s):  
Nervous System ◽  
Molecular Mechanisms ◽  
Neuronal Cells ◽  
Industrial Applications ◽  
Mammalian Brain ◽  
Human Environment ◽  
Developmental Abnormalities ◽  
Increased Risk ◽  
Wide Range ◽  
And Function

Benzophenone-3 (2-hydroxy-4-methoxybenzophenone, oxybenzone, or BP-3) is one of the most frequently used UV radiation absorbents, which are commonly referred to as sunscreen filters. Its widespread use in industrial applications provides protection against the photodegradation of a wide range of products but at the same time creates the risk of human exposure to benzophenone-3 unbeknownst to the individuals exposed. Topically applied benzophenone-3 penetrates individual skin layers, enters the bloodstream, and is excreted in the urine. In addition, benzophenone-3 easily crosses the placental barrier, which creates the risk of exposure to this substance in the prenatal period. Despite the widespread use and occurrence of benzophenone-3 in the human environment, little knowledge of the mechanisms underlying the effect of benzophenone-3 on the nervous system was available until recently. Only the most recent research, including studies by our group, has enabled the identification of new molecular mechanisms through which benzophenone-3 affects embryonic neuronal cells and the developing mammalian brain. Benzophenone-3 has been shown to induce neurotoxicity and apoptotic processes and inhibit autophagy in embryonic neuronal cells. Benzophenone-3 also alters expression and impairs function of receptors necessary for the proper development and function of the nervous system. The most worrying finding seems to be that benzophenone-3 contributes to an increased risk of developmental abnormalities and/or epigenetically based degeneration of neuronal cells by changing the epigenetic status of neuronal cells.

scholarly journals Pervasive Suicidal Integrases in Deep-Sea Archaea

2020 ◽  
Vol 37 (6) ◽  
pp. 1727-1743
Author(s):  
Catherine Badel ◽  
Violette Da Cunha ◽  
Patrick Forterre ◽  
Jacques Oberto
Keyword(s):  
Molecular Mechanisms ◽  
Integration Site ◽  
Biological Properties ◽  
Host Genome ◽  
Hyperthermophilic Archaea ◽  
Site Specificity ◽  
Reading Frame ◽  
Wide Range ◽  
Variable Integration ◽  
Different Origins

Abstract Mobile genetic elements (MGEs) often encode integrases which catalyze the site-specific insertion of their genetic information into the host genome and the reverse reaction of excision. Hyperthermophilic archaea harbor integrases belonging to the SSV-family which carry the MGE recombination site within their open reading frame. Upon integration into the host genome, SSV integrases disrupt their own gene into two inactive pseudogenes and are termed suicidal for this reason. The evolutionary maintenance of suicidal integrases, concurring with the high prevalence and multiples recruitments of these recombinases by archaeal MGEs, is highly paradoxical. To elucidate this phenomenon, we analyzed the wide phylogenomic distribution of a prominent class of suicidal integrases which revealed a highly variable integration site specificity. Our results highlighted the remarkable hybrid nature of these enzymes encoded from the assembly of inactive pseudogenes of different origins. The characterization of the biological properties of one of these integrases, IntpT26-2 showed that this enzyme was active over a wide range of temperatures up to 99 °C and displayed a less-stringent site specificity requirement than comparable integrases. These observations concurred in explaining the pervasiveness of these suicidal integrases in the most hyperthermophilic organisms. The biochemical and phylogenomic data presented here revealed a target site switching system operating on highly thermostable integrases and suggested a new model for split gene reconstitution. By generating fast-evolving pseudogenes at high frequency, suicidal integrases constitute a powerful model to approach the molecular mechanisms involved in the generation of active genes variants by the recombination of proto-genes.

scholarly journals Chromosomal Targeting by the Type III-A CRISPR-Cas System Can Reshape Genomes in Staphylococcus aureus

mSphere ◽  
2017 ◽  
Vol 2 (6) ◽  
Author(s):  
Jing Guan ◽  
Wanying Wang ◽  
Baolin Sun
Keyword(s):  
Staphylococcus Aureus ◽  
Molecular Mechanisms ◽  
Mobile Genetic Elements ◽  
Industrial Applications ◽  
Partial Deletion ◽  
Content Type ◽  
Genetic Elements ◽  
Type Iii ◽  
Wide Range ◽  
Novel Strategy

ABSTRACT Staphylococcus aureus is a pathogen that can cause a wide range of infections in humans. Studies have suggested that CRISPR-Cas systems can drive the loss of integrated mobile genetic elements (MGEs) by chromosomal targeting. Here we demonstrate that CRISPR-mediated cleavage contributes to the partial deletion of integrated SCCmec in methicillin-resistant S. aureus (MRSA), which provides a strategy for the treatment of MRSA infections. The spacer within artificial CRISPR arrays should contain more than 25 nucleotides for immunity, and consecutive trinucleotide pairings between a selected target and the 5′ tag of crRNA can block targeting. These findings add to our understanding of the molecular mechanisms of the type III-A CRISPR-Cas system and provide a novel strategy for the exploitation of engineered CRISPR immunity against integrated MGEs in bacteria for clinical and industrial applications. CRISPR-Cas (clustered regularly interspaced short palindromic repeat [CRISPR]-CRISPR-associated protein [Cas]) systems can provide protection against invading genetic elements by using CRISPR RNAs (crRNAs) as a guide to locate and degrade the target DNA. CRISPR-Cas systems have been classified into two classes and five types according to the content of cas genes. Previous studies have indicated that CRISPR-Cas systems can avoid viral infection and block plasmid transfer. Here we show that chromosomal targeting by the Staphylococcus aureus type III-A CRISPR-Cas system can drive large-scale genome deletion and alteration within integrated staphylococcal cassette chromosome mec (SCCmec). The targeting activity of the CRISPR-Cas system is associated with the complementarity between crRNAs and protospacers, and 10- to 13-nucleotide truncations of spacers partially block CRISPR attack and more than 13-nucleotide truncation can fully abolish targeting, suggesting that a minimal length is required to license cleavage. Avoiding base pairings in the upstream region of protospacers is also necessary for CRISPR targeting. Successive trinucleotide complementarity between the 5′ tag of crRNAs and protospacers can disrupt targeting. Our findings reveal that type III-A CRISPR-Cas systems can modulate bacterial genome stability and may serve as a high-efficiency tool for deleting resistance or virulence genes in bacteria. IMPORTANCE Staphylococcus aureus is a pathogen that can cause a wide range of infections in humans. Studies have suggested that CRISPR-Cas systems can drive the loss of integrated mobile genetic elements (MGEs) by chromosomal targeting. Here we demonstrate that CRISPR-mediated cleavage contributes to the partial deletion of integrated SCCmec in methicillin-resistant S. aureus (MRSA), which provides a strategy for the treatment of MRSA infections. The spacer within artificial CRISPR arrays should contain more than 25 nucleotides for immunity, and consecutive trinucleotide pairings between a selected target and the 5′ tag of crRNA can block targeting. These findings add to our understanding of the molecular mechanisms of the type III-A CRISPR-Cas system and provide a novel strategy for the exploitation of engineered CRISPR immunity against integrated MGEs in bacteria for clinical and industrial applications.

Regulation, Diversity and Evolution of Boron Transporters in Plants

2021 ◽  
Author(s):  
Amarachukwu Faith Onuh ◽  
Kyoko Miwa
Keyword(s):  
Plant Species ◽  
Molecular Mechanisms ◽  
Mineral Nutrient ◽  
Cell Level ◽  
Pectic Polysaccharide ◽  
Homologous Genes ◽  
Level Ii ◽  
Wide Range ◽  
Rhamnogalacturonan Ii ◽  
High Concentrations

Abstract Boron (B) is an essential trace element in plants, and borate cross-linking of pectic polysaccharide rhamnogalacturonan-II (RG-II) in cell walls is required for normal cell growth. High concentrations of B are toxic to cells. Therefore, plants need to control B transport to respond to B conditions in the environment. Over the past two decades, genetic analyses of Arabidopsis thaliana have revealed that B transport is governed by two types of membrane transport molecules: NIPs (nodulin-26-like intrinsic proteins), which facilitate boric acid permeation, and BORs, which export borate from cells. In this article, we review recent findings on the (i) regulation at the cell level, (ii) diversity among plant species and (iii) evolution of these B transporters in plants. We first describe the systems regulating these B transporters at the cell level, focusing on the molecular mechanisms underlying the polar localization of proteins and B-dependent expression, as well as their physiological significance in A. thaliana. Then, we examine the presence of homologous genes and characterize the functions of NIPs and BORs in B homeostasis, in a wide range of plant species, including Brassica napus, Oryza sativa and Zea mays. Finally, we discuss the evolutionary aspects of NIPs and BORs as B transporters, and the possible relationship between the diversification of B transport and the occurrence of RG-II in plants. This review considers the sophisticated systems of B transport that are conserved among various plant species, which were established to meet mineral nutrient requirements.

scholarly journals A Review on Carbon Nanotubes (CNT): Structure, Synthesis, Purification and Properties for Modern day Applications

2021 ◽  
Author(s):  
Nur-Azzah Afifah Binti Taib ◽  
Md. Rezaur Rahman ◽  
Mohammed Mahbubul Matin ◽  
Jamal Uddin ◽  
Muhammad Khusairy Bin Bakri ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Arc Discharge ◽  
Chemical Vapor ◽  
Biological Properties ◽  
Industrial Applications ◽  
Structural Reinforcement ◽  
Structure Synthesis ◽  
Purification And Properties ◽  
Wide Range ◽  
Walled Cnts

Abstract Carbon nanotubes (CNTs), composed of graphene/graphite sheets, have been used since the 1990s and become one of the most important materials owing to its massive applications in energy, environmental and life sciences. In general, there are two types of known CNTs such as single-walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs). They have broader and novel fields of application in the fabric and textile industries, wastewater treatment, energy storage, and also as structural reinforcement materials. CNTs are reported to synthesize by arc discharge, laser ablation and chemical vapor deposition (CVD) methods where CVD technique is found to be the most versatile and largely used method. In all the methods synthesized CNTs contain various degrees of impurities which are purified by oxidation treatment, ultra-sonication, magnetic purification, etc. CNTs have wide range of industrial applications due to their remarkable mechanical, thermal, electrical, chemical and biological properties. In this review, medical and biomedical applications of CNTs and CNTs-based composites are specially focused due to their significant applications in these fields along with their structure, classification, preparation and related properties. Besides, CNTs’ toxicity and biosafety, especially on the human body, are also discussed in this review article.

scholarly journals Cloning and Characterization of Two Putative P-Type ATPases from the Marine Microalga Dunaliella maritima Similar to Plant H+-ATPases and Their Gene Expression Analysis under Conditions of Hyperosmotic Salt Shock

Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2667
Author(s):  
Dmitrii A. Matalin ◽  
Dmitrii E. Khramov ◽  
Alexey V. Shuvalov ◽  
Vadim S. Volkov ◽  
Yurii V. Balnokin ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Low Level ◽  
Salt Shock ◽  
Freshwater Organisms ◽  
Marine Microalga ◽  
Wide Range ◽  
History Of ◽  
Na Ions ◽  
High Concentrations ◽  
P Type

The green microalga genus Dunaliella is mostly comprised of species that exhibit a wide range of salinity tolerance, including inhabitants of hyperhaline reservoirs. Na+ content in Dunaliella cells inhabiting saline environments is maintained at a fairly low level, comparable to that in the cells of freshwater organisms. However, despite a long history of studying the physiological and molecular mechanisms that ensure the ability of halotolerant Dunaliella species to survive at high concentrations of NaCl, the question of how Dunaliella cells remove excess Na+ ions entering from the environment is still debatable. For thermodynamic reasons it should be a primary active mechanism; for example, via a Na+-transporting ATPase, but the molecular identification of Na+-transporting mechanism in Dunaliella has not yet been carried out. Formerly, in the euryhaline alga D. maritima, we functionally identified Na+-transporting P-type ATPase in experiments with plasma membrane (PM) vesicles which were isolated from this alga. Here we describe the cloning of two putative P-type ATPases from D. maritima, DmHA1 and DmHA2. Phylogenetic analysis showed that both ATPases belong to the clade of proton P-type ATPases, but the similarity between DmHA1 and DmHA2 is not high. The expression of DmHA1 and DmHA2 in D. maritima cells under hyperosmotic salt shock was studied by qRT-PCR. Expression of DmHA1 gene decreases and remains at a relatively low level during the response of D. maritima cells to hyperosmotic salt shock. In contrast, expression of DmHA2 increases under hyperosmotic salt shock. This indicates that DmHA2 is important for overcoming hyperosmotic salt stress by the algal cells and as an ATPase it is likely directly involved in transport of Na+ ions. We assume that it is the DmHA2 ATPase that represents the Na+-transporting ATPase.

Protein expression changes in cells inoculated with Equine Influenza Virus: antibody microarray analysis

2013 ◽  
Vol 16 (4) ◽  
pp. 663-669
Author(s):  
W. Rozek ◽  
M. Kwasnik ◽  
J.F. Zmudzinski
Keyword(s):  
Influenza Virus ◽  
Protein Quality ◽  
Biological Properties ◽  
Regulation Of Transcription ◽  
Equine Influenza Virus ◽  
Virus Antibody ◽  
Antibody Microarray ◽  
Equine Influenza ◽  
Microarray Technique ◽  
In Cells

AbstractChanges in the level of cellular proteins in cells inoculated with equine influenza virus H7N7 and H3N8 were studied with microarray technique. H3N8 induced pro-apoptotic proteins while H7N7 induced both pro- as well as anti-apoptotic factors. The higher level of some cytoskeleton components and proteins involved in the protein quality control was recorded. Relatively high number of proteins involved in the regulation of transcription was down-regulated. The pattern of changes observed for H7N7 and H3N8 may reflect differences in the biological properties of both serotypes.

Substituent Effects on the Thermal Decomposition of Phosphate Esters on Ferrous Surfaces

2019 ◽  
Author(s):  
James Ewen ◽  
Carlos Ayestaran Latorre ◽  
Arash Khajeh ◽  
Joshua Moore ◽  
Joseph Remias ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Film Formation ◽  
Substituent Effects ◽  
Vapour Phase ◽  
Industrial Applications ◽  
Phosphate Esters ◽  
Antiwear Additives ◽  
Formation Mechanisms ◽  
Phosphate Ester ◽  
Wide Range

<p>Phosphate esters have a wide range of industrial applications, for example in tribology where they are used as vapour phase lubricants and antiwear additives. To rationally design phosphate esters with improved tribological performance, an atomic-level understanding of their film formation mechanisms is required. One important aspect is the thermal decomposition of phosphate esters on steel surfaces, since this initiates film formation. In this study, ReaxFF molecular dynamics simulations are used to study the thermal decomposition of phosphate esters with different substituents on several ferrous surfaces. On Fe<sub>3</sub>O<sub>4</sub>(001) and α-Fe(110), chemisorption interactions between the phosphate esters and the surfaces occur even at room temperature, and the number of molecule-surface bonds increases as the temperature is increased from 300 to 1000 K. Conversely, on hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>, most of the molecules are physisorbed, even at high temperature. Thermal decomposition rates were much higher on Fe<sub>3</sub>O<sub>4</sub>(001) and particularly α-Fe(110) compared to hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>. This suggests that water passivates ferrous surfaces and inhibits phosphate ester chemisorption, decomposition, and ultimately film formation. On Fe<sub>3</sub>O<sub>4</sub>(001), thermal decomposition proceeds mainly through C-O cleavage (to form surface alkyl and aryl groups) and C-H cleavage (to form surface hydroxyls). The onset temperature for C-O cleavage on Fe<sub>3</sub>O<sub>4</sub>(001) increases in the order: tertiary alkyl < secondary alkyl < primary linear alkyl ≈ primary branched alkyl < aryl. This order is in agreement with experimental observations for the thermal stability of antiwear additives with similar substituents. The results highlight surface and substituent effects on the thermal decomposition of phosphate esters which should be helpful for the design of new molecules with improved performance.</p>

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