scholarly journals Copper nanoparticles as modulator of active bacterial population and their physiology in ecosphere

2021 ◽  
Author(s):  
Ali Alboloushi ◽  
Absar Alum ◽  
Morteza Abbaszadegan
Keyword(s):  
Copper Nanoparticles ◽  
Biological Treatment ◽  
Bacterial Population ◽  
Bacterial Species ◽  
Consumer Products ◽  
Log Reduction ◽  
Treatment Processes ◽  
The Impact ◽  
Toxicity Pathways

The widespread use of nanoparticles (NPs) in industrial and consumer products has resulted in their emergence as significant environmental contaminants that can potentially modulate the role of bacteria in environment. This study examines the impact of different sizes of Copper nanoparticles (CuNPs) on the population and physiology of environmentally relevant gram positive (Bacillus) and gam negative (Alcaligenes, and Pseudomonas) bacteria. In general, exposure to CuNPs resulted in 4 to >6 log inactivation in bacterial population. More specifically, after 2hr exposure of Alcaligenes and Pseudomonas to 50 CuNPs, 5.75 and 6.64 log reduction noted, respectively; and their exposure to 100 CuNPs resulted in 5.97 and 6.58 log reduction, respectively. A similar exposure of laboratory and environmental isolates of Bacillus to 50 and 100 CuNPs resulted in 4.84, 4.16 and 4.35, 3.61 log reduction, correspondingly. The exposure induced elicitation of different toxicity pathways in the test bacteria. Bacterial exposure to 50 CuNPs resulted in elevated levels of LDH in Pseudomonas, in contrast these levels decreased in Alcaligenes and Bacillus. Our toxicity studies showed that exposure to CuNP can have various levels of metabolic and cellular modulation in bacterial species, suggesting that the presence of CuNPs in environment can potentially impact the pollutants-attenuation-role of bacteria in environments such as wastewater biological treatment processes.

Of: The Role of Molecular Methods in Evaluating Biological Treatment Processes, B. E. Rittmann

2003 ◽  
Vol 75 (3) ◽  
pp. 283-284
Author(s):  
R. Iranpour ◽  
F. Alatriste-Mondragon ◽  
S. V. Diaz-Perez ◽  
H. H. J. Cox
Keyword(s):  
Biological Treatment ◽  
Molecular Methods ◽  
Treatment Processes

A Channel-Specific Analysis of the Risk Information Seeking and Processing (RISP) Model: The Role of Relevant Channel Beliefs and Perceived Information Gathering Capacity

2020 ◽  
Vol 42 (3) ◽  
pp. 279-312
Author(s):  
Yoori Hwang ◽  
Se-Hoon Jeong
Keyword(s):  
Information Seeking ◽  
Risk Information ◽  
Information Gathering ◽  
Consumer Products ◽  
The Other ◽  
Toxic Chemicals ◽  
Independent Effect ◽  
Specific Analysis ◽  
The Impact

The risk information seeking and processing (RISP) model posits that information insufficiency could lead to information seeking, and the effect could be moderated by relevant channel beliefs and perceived information gathering capacity. The RISP model is tested in the context of Koreans’ risk information seeking and processing related to toxic chemicals in consumer products. The present study showed that the impact of information insufficiency was moderated by relevant channel beliefs. On the other hand, the impact of information insufficiency was not moderated by perceived information gathering capacity; instead, perceived information gathering capacity had an independent effect on information seeking.

scholarly journals c-di-AMP, a likely master regulator of bacterial K+ homeostasis machinery, activates a K+ exporter

2021 ◽  
Vol 118 (14) ◽  
pp. e2020653118
Author(s):  
Tatiana B. Cereija ◽  
João P. L. Guerra ◽  
João M. P. Jorge ◽  
João H. Morais-Cabral
Keyword(s):  
Bacterial Species ◽  
Structural Data ◽  
Regulatory Function ◽  
Dna Integrity ◽  
Master Regulator ◽  
Quantitative Evidence ◽  
Physiological Properties ◽  
The Impact

bis-(3′,5′)-cyclic diadenosine monophosphate (c-di-AMP) is a second messenger with roles in virulence, cell wall and biofilm formation, and surveillance of DNA integrity in many bacterial species, including pathogens. Strikingly, it has also been proposed to coordinate the activity of the components of K+ homeostasis machinery, inhibiting K+ import, and activating K+ export. However, there is a lack of quantitative evidence supporting the direct functional impact of c-di-AMP on K+ transporters. To gain a detailed understanding of the role of c-di-AMP on the activity of a component of the K+ homeostasis machinery in B. subtilis, we have characterized the impact of c-di-AMP on the functional, biochemical, and physiological properties of KhtTU, a K+/H+ antiporter composed of the membrane protein KhtU and the cytosolic protein KhtT. We have confirmed c-di-AMP binding to KhtT and determined the crystal structure of this complex. We have characterized in vitro the functional properties of KhtTU and KhtU alone and quantified the impact of c-di-AMP and of pH on their activity, demonstrating that c-di-AMP activates KhtTU and that pH increases its sensitivity to this nucleotide. Based on our functional and structural data, we were able to propose a mechanism for the activation of KhtTU by c-di-AMP. In addition, we have analyzed the impact of KhtTU in its native bacterium, providing a physiological context for the regulatory function of c-di-AMP and pH. Overall, we provide unique information that supports the proposal that c-di-AMP is a master regulator of K+ homeostasis machinery.

Is the role of human female reproductive tract microbiota underestimated?

2017 ◽  
Vol 8 (3) ◽  
pp. 327-343 ◽  
Author(s):  
D. Kamińska ◽  
M. Gajecka
Keyword(s):  
Reproductive Tract ◽  
Bacterial Species ◽  
Bacterial Community Composition ◽  
Intrauterine Infection ◽  
Extensive Study ◽  
Female Reproductive Tract ◽  
Foetal Development ◽  
Culture Independent ◽  
The Impact

An issue that is currently undergoing extensive study is the influence of human vaginal microbiota (VMB) on the health status of women and their neonates. Healthy women are mainly colonised with lactobacilli such as Lactobacillus crispatus, Lactobacillus jensenii, and Lactobacillus iners; however, other bacteria may be elements of the VMB, particularly in women with bacterial vaginosis. The implementation of culture-independent molecular methods in VMB characterisation, especially next-generation sequencing, have provided new information regarding bacterial diversity in the vagina, revealing a large number of novel, fastidious, and/or uncultivated bacterial species. These molecular studies have contributed new insights regarding the role of bacterial community composition. In this study, we discuss recent findings regarding the reproductive tract microbiome. Not only bacteria but also viruses and fungi constitute important components of the reproductive tract microbiome. We focus on aspects related to the impact of the maternal microbiome on foetal development, as well as the establishment of the neonatal microbiomes, including the placenta microbiome, and the haematogenous source of intrauterine infection. We also discuss whether the role of the vaginal microbiome is currently understood and appreciated.

scholarly journals Phage selection for bacterial cheats leads to population decline

2015 ◽  
Vol 282 (1818) ◽  
pp. 20152207 ◽  
Author(s):  
Marie Vasse ◽  
Clara Torres-Barceló ◽  
Michael E. Hochberg
Keyword(s):  
Population Biology ◽  
Social Evolution ◽  
Bacterial Population ◽  
Bacterial Species ◽  
Population Decline ◽  
Lytic Phage ◽  
Social Strategies ◽  
Selection For ◽  
Phage Selection ◽  
The Impact

While predators and parasites are known for their effects on bacterial population biology, their impact on the dynamics of bacterial social evolution remains largely unclear. Siderophores are iron-chelating molecules that are key to the survival of certain bacterial species in iron-limited environments, but their production can be subject to cheating by non-producing genotypes. In a selection experiment conducted over approximately 20 bacterial generations and involving 140 populations of the pathogenic bacterium Pseudomonas aeruginosa PAO1, we assessed the impact of a lytic phage on competition between siderophore producers and non-producers. We show that the presence of lytic phages favours the non-producing genotype in competition, regardless of whether iron use relies on siderophores. Interestingly, phage pressure resulted in higher siderophore production, which constitutes a cost to the producers and may explain why they were outcompeted by non-producers. By the end of the experiment, however, cheating load reduced the fitness of mixed populations relative to producer monocultures, and only monocultures of producers managed to grow in the presence of phage in situations where siderophores were necessary to access iron. These results suggest that public goods production may be modulated in the presence of natural enemies with consequences for the evolution of social strategies.

Gut Prevotella as a possible biomarker of diet and its eubiotic versus dysbiotic roles: a comprehensive literature review

2019 ◽  
Vol 122 (2) ◽  
pp. 131-140 ◽  
Author(s):  
Gabriela Precup ◽  
Dan-Cristian Vodnar
Keyword(s):  
Literature Review ◽  
Dietary Patterns ◽  
Bacterial Species ◽  
Cancer Type ◽  
High Genetic Diversity ◽  
The Metabolic Syndrome ◽  
Comprehensive Literature Review ◽  
Potential Biomarker ◽  
The Impact

AbstractThe gut microbiota has a profound impact on human health. Emerging data show that dietary patterns are associated with different communities of bacterial species within the gut. Prevotella species have been correlated with plant-rich diets, abundant in carbohydrates and fibres. Dysbiosis within the gut ecosystem has been associated with the development of non-communicable diseases such as obesity, the metabolic syndrome, inflammatory bowel disease, irritable bowel syndrome, colorectal cancer, type 1 diabetes, allergies and other diseases. The purpose of this comprehensive literature review was to evaluate the available data on the impact of diet on the Prevotella genus, as a dietary fibre fermenter in the gut as well as its implications as a potential biomarker for homeostasis or disease state through its metabolite signature. Studies were identified by conducting PubMed, Web of Science Core Collection and Google Scholar electronic searches. We found eighty-five publications reporting the impact of dietary patterns on gut microbial communities, including Prevotella or Prevotella/Bacteroides ratio in particular. Moreover, the role of Prevotella species on health status was also evaluated. Prevotella possess a high genetic diversity, representing one of the important groups found in the oral cavity and large intestine of man. The gut commensal Prevotella bacteria contribute to polysaccharide breakdown, being dominant colonisers of agrarian societies. However, studies also suggested a potential role of Prevotella species as intestinal pathobionts. Further metagenomic studies are needed in order to reveal health- or disease-modulating properties of Prevotella species in the gut.

scholarly journals A Review of Manganese(III) (Oxyhydr)Oxides Use in Advanced Oxidation Processes

Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 5748
Author(s):  
Daqing Jia ◽  
Khalil Hanna ◽  
Gilles Mailhot ◽  
Marcello Brigante
Keyword(s):  
Singlet Oxygen ◽  
Advanced Oxidation Processes ◽  
Inorganic Ions ◽  
Advanced Oxidation ◽  
Solution Ph ◽  
Oxidation Processes ◽  
Treatment Processes ◽  
Activation Mechanisms ◽  
The Impact

The key role of trivalent manganese (Mn(III)) species in promoting sulfate radical-based advanced oxidation processes (SR-AOPs) has recently attracted increasing attention. This review provides a comprehensive summary of Mn(III) (oxyhydr)oxide-based catalysts used to activate peroxymonosulfate (PMS) and peroxydisulfate (PDS) in water. The crystal structures of different Mn(III) (oxyhydr)oxides (such as α-Mn2O3, γ-MnOOH, and Mn3O4) are first introduced. Then the impact of the catalyst structure and composition on the activation mechanisms are discussed, as well as the effects of solution pH and inorganic ions. In the Mn(III) (oxyhydr)oxide activated SR-AOPs systems, the activation mechanisms of PMS and PDS are different. For example, both radical (such as sulfate and hydroxyl radical) and non-radical (singlet oxygen) were generated by Mn(III) (oxyhydr)oxide activated PMS. In comparison, the activation of PDS by α-Mn2O3 and γ-MnOOH preferred to form the singlet oxygen and catalyst surface activated complex to remove the organic pollutants. Finally, research gaps are discussed to suggest future directions in context of applying radical-based advanced oxidation in wastewater treatment processes.

scholarly journals A Linguistic (Critical Discourse) Analysis of Consumer Products’ Advertising in Nigeria

2019 ◽  
Vol 10 (2) ◽  
pp. 159
Author(s):  
Oyedokun Alli ◽  
Wasiu Ademola
Keyword(s):  
Critical Discourse Analysis ◽  
Great Influence ◽  
Consumer Products ◽  
Purchasing Decisions ◽  
Role Of Government ◽  
Advertising Industry ◽  
Proper Role ◽  
Selling Point ◽  
The Impact

Language is the chief means by which humans communicate among themselves; it is also a veritable means of socialisation. In essence, language is an important arsenal used to influence others around us. Clive Johnson and Jackie Keddie (2011) assert that “the impact of what and how we communicate can be very profound for others”. This paper examines the use of language in the advertising industry and posits that in advertising, not only is language used to inform or sensitize, but it is also used to deceive. Language has immense power, and its impact depends entirely on how we wield it. Advertising has a great influence on our purchasing decisions. Consumers are exposed to countless commercial messages everyday “persuading them to buy brand name products”. This is achieved through certain contrivances, which the paper fully discusses. The searchlight of this paper beams on such questions as: does advertising tempt us into buying things we don’t need; does it affect us subliminally in ways we can’t control; how much latitude should marketers have in the kind of products they promote and how they advertise them; do consumers have some responsibilities in the process; what is the proper role of government, especially in protecting the consumers? In sum, the paper sets for itself the task of determining the “border line” between persuasion and deception, in the language of advertisement. It finds that through the subtle means of “appealing” and “persuading, certain deceptive contrivances and even outright falsehood are sued to hoodwink the consumer. The implications are that consumers are “tricked” to buy what they don’t really need; advertisers “overstretch” claim on their products and services; and, finally the advertising, not the product itself, becomes the selling point. It also recommends among others that the National Broadcasting Commission (NBC), Advertisement Practitioners’ Council of Nigeria and such other regulatory agencies should be empowered to verify all claims in advertisements before such claims are published.

scholarly journals Role of Toll-Like Receptor 13 in Innate Immune Recognition of Group B Streptococci

2014 ◽  
Vol 82 (12) ◽  
pp. 5013-5022 ◽  
Author(s):  
Giacomo Signorino ◽  
Nastaran Mohammadi ◽  
Francesco Patanè ◽  
Marco Buscetta ◽  
Mario Venza ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Ribosomal Subunit ◽  
23S Rrna ◽  
Immune Recognition ◽  
Toll Like Receptor ◽  
Host Defenses ◽  
Bacterial Rna ◽  
Group B ◽  
The Impact

ABSTRACTMurine Toll-like receptor 13 (TLR13), an endosomal receptor that is not present in humans, is activated by an unmethylated motif present in the large ribosomal subunit of bacterial RNA (23S rRNA). Little is known, however, of the impact of TLR13 on antibacterial host defenses. Here we examined the role of this receptor in the context of infection induced by the model pathogen group B streptococcus (GBS). To this end, we used bacterial strains masked from TLR13 recognition by virtue of constitutive expression of the ErmC methyltransferase, which results in dimethylation of the 23S rRNA motif at a critical adenine residue. We found that TLR13-mediated rRNA recognition was required for optimal induction of tumor necrosis factor alpha and nitrous oxide in dendritic cell and macrophage cultures stimulated with heat-killed bacteria or purified bacterial RNA. However, TLR13-dependent recognition was redundant when live bacteria were used as a stimulus. Moreover, masking bacterial rRNA from TLR13 recognition did not increase the ability of GBS to avoid host defenses and replicatein vivo. In contrast, increased susceptibility to infection was observed under conditions in which signaling by all endosomal TLRs was abolished, i.e., in mice with a loss-of-function mutation in the chaperone protein UNC93B1. Our data lend support to the conclusion that TLR13 participates in GBS recognition, although blockade of the function of this receptor can be compensated for by other endosomal TLRs. Lack of selective pressure by bacterial infections might explain the evolutionary loss of TLR13 in humans. However, further studies using different bacterial species are needed to prove this hypothesis.

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