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Topic Review
The Role of Metallophores in Staphylococcus aureus
Staphylococcus aureus (S. aureus) is considered one of the most widespread infectious bacteria. It is found in the environment as well as being part of the human skin and nasal microbiota. Normally, S. aureus is harmless on healthy skin, but once it enters the blood or internal tissues, diverse infections occur including pneumonia, infection of surgical site and nosocomial bacteremia. Systemic S. aureus infection depends on the bacteria breaking through the epithelial protective layer. The incidence rate of this serious medical condition is between 20 and 50 cases/100,000 per year, with fatality rate ranging from 10% to 30%. Moreover, S. aureus forms biofilms that are associated with medical device infections such as prosthetic joints and endocarditis. The prevalence of antibiotic resistance S. aureus isolates, methicillin-resistant S. aureus (MRSA), is posing a serious problem for combating infectious diseases caused by this pathogen.
  • 943
  • 28 Oct 2022
Topic Review
Methicillin-Resistant Staphylococci in Animals and Food Products
Staphylococci are Gram-positive bacteria responsible for a wide variety of suppurative infections in humans and animals. Methicillin resistance acquisition is due to the integration of the staphylococcal cassette chromosome mec (SCCmec), which contains the mecA gene conferring β-lactam resistance. Methicillin-resistance in Staphylococci (MRS) pose a specific problem as they are in general more difficult to treat and may eventually result in death. Those MRS are now also increasingly found in different animal species and may compromise animal health as well as human health through the transmission of those MRS from animals to humans. As such it is important to know the situation of  MRS in animals and in foods.
  • 943
  • 07 Jul 2022
Topic Review
Metals and Metalloids by Actinobacteria
Actinobacteria include high GC bacteria that inhabit a wide range of terrestrial and aquatic ecological niches, where they play essential roles in recycling or transforming organic and inorganic substances. The metal(loid) tolerance and/or resistance of several members of this phylum rely on mechanisms such as biosorption and extracellular sequestration by siderophores and extracellular polymeric substances (EPS), bioaccumulation, biotransformation, and metal efflux processes, which overall contribute to maintaining metal homeostasis.
  • 942
  • 08 Jan 2021
Topic Review
Immune Response to Necrotic Enteritis in Broilers
Clostridium perfringens type A and C are the primary etiological agents associated with necrotic enteritis (NE) in poultry. The predisposing factors implicated in the incidence of NE changes the physical properties of the gut, immunological status of birds, and disrupt the gut microbial homeostasis, causing an over-proliferation of C. perfringens. The principal virulence factors contributing to the pathogenesis of NE are the α-toxin, β-toxin, and NetB toxin. The immune response to NE in poultry is mediated by the Th1 pathway or cytotoxic T-lymphocytes. C. perfringens type A and C are also pathogenic in humans, and hence are of public health significance. C. perfringens intoxications are the third most common bacterial foodborne disease after Salmonella and Campylobacter.
  • 940
  • 28 Oct 2022
Topic Review
Liquid Fermentation of Edible and Medicinal Fungi
Liquid fermentation of edible and medicinal fungi involves cultivating and growing fungi in a liquid medium, providing optimal conditions for their growth and fermentation. This method offers advantages over traditional solid-state fermentation, such as better control of environmental factors, higher yield and purity, and faster production cycles. It also enables the extraction of bioactive compounds with therapeutic potential, which can be utilized in pharmaceuticals, nutraceuticals, cosmetics, and functional foods. Overall, it is a modern technique for producing high-quality fungal products with enhanced bioactive properties.
  • 939
  • 21 Sep 2023
Topic Review
Rhizosphere Microbial Communities and Heavy-Metals
The rhizosphere is a microhabitat where there is an intense chemical dialogue between plants and microorganisms. The two coexist and develop synergistic actions, which can promote plants’ functions and productivity, but also their capacity to respond to stress conditions, including heavy metal (HM) contamination.
  • 937
  • 28 Jul 2021
Topic Review
CRC and Gut Microbiota
The gut microbiota plays an important role in maintaining homeostasis in the human body, and the disruption of these communities can lead to compromised host health and the onset of disease.
  • 936
  • 23 Jun 2021
Topic Review
Avian Reovirus
Avian reoviruses belong to the genus Orthoreovirus, and Reoviridae family. They are non-enveloped viruses that undergo replication in the cytoplasm of infected cells. It has icosahedral symmetry and contains a double-shelled arrangement of surface protein. Virus particles can range between 70–80 nm. Morphologically, the virus is a double stranded RNA virus that is composed of ten segments. The genome and proteins that are encoded by the genome can be separated into three different sizes ranging from small, medium, or large. Of the eleven proteins that are encoded for by the genome, two are nonstructural, while the remaining nine are structural. Avian reoviruses can withstand a pH range of 3.0–9.0. Ambient temperatures are suitable for the survival of these viruses, which become inactive at 56 °C in less than an hour. Common areas where this virus can survive include galvanized metal, glass, rubber, feathers, and wood shavings. Avian reovirus can survive for up to ten days on these common areas in addition to up to ten weeks in water. Cultivation and observation of the effects of avian reovirus is most often performed in chicken embryos. If infected into the yolk sac, the embryo will succumb to death accompanied by hemorrhaging of the embryos and cause the foci on the liver to appear yellowish-green. There are several primary chicken cell cultures/areas that are susceptible to avian reoviruses, which include the lungs, liver, kidney, and fibroblasts of the chick embryo. Of the following susceptible areas, liver cells from the chick embryo have been found to be the most sensitive for primary isolation from clinical material. Typically, the CPE effect of avian reoviruses is the production of syncytia. CPE, or cytopathic effects are the visible changes in a host cell that takes place because of viral infection. Syncytia is a single cell or cytoplasmic mass containing several nuclei, formed by fusion of cells or by division of nuclei.
  • 933
  • 14 Nov 2022
Topic Review
Microbe-Assisted Remediation of Crude-Oil-Contaminated Environment
Crude oil contamination is an emerging environmental concern on a global scale due to inadvertent oil leakage. Oil spillage and discharges frequently happen as a consequence of explosion incidents during oilfield drilling; leakage from oil and gas pipelines and reservoirs, fuel tankers, and well waxing; and during overhauls of refineries and petrochemical manufacturing equipment. Crude oil and its products damage water and air quality and also reduce soil fertility. Crude oil can harm plants by clogging soil pores, reducing soil aeration and water permeability, which can have both ecological and toxicological effects and disrupt the soil’s natural structure. Aside from these environmental concerns, one of the most serious consequences of such anthropogenic emissions is current global climate change. Crude oil contamination not only impacts different ecosystems but also influences global socio-economic status.
  • 932
  • 25 Apr 2023
Topic Review
Microsporidian Spore Germination
Microsporidia are a large group of mysterious obligate intracellular eukaryotic parasites. The microsporidian spore can survive in the absence of nutrients for years under harsh conditions and germinate within seconds under the stimulation of environmental changes like pH and ions. During germination, microsporidia experience an increase in intrasporal osmotic pressure, which leads to an influx of water into the spore, followed by swelling of the polaroplasts and posterior vacuole, which eventually fires the polar filament (PF). Infectious sporoplasm was transported through the extruded polar tube (PT) and delivered into the host cell. 
  • 932
  • 08 Oct 2023
Topic Review
Chaperone-Usher Fimbriae
Chaperone-usher fimbriae (CU) are linear, unbranching, outer-membrane pili secreted by Gram-negative bacteria through the chaperone-usher system rather than through type IV secretion or extracellular nucleation systems. These fimbriae are built up out of modular pilus subunits, which are transported into the periplasm in a Sec dependent manner. Chaperone-usher secreted fimbriae are important pathogenicity factors facilitating host colonisation, localisation and biofilm formation in clinically important species such as UPEC (uropathogenic Escherichia coli) and Pseudomonas aeruginosa.
  • 930
  • 15 Nov 2022
Topic Review
Juglans regia L. Pellicle Extract
The difficulty to treat resistant strains-related hospital-acquired infections (HAIs) promoted the study of phytoextracts, known sources of bioactive molecules. Accordingly, in the present study, the pharmacological activities of Juglans regia (L.) pellicle extract (WPE) were investigated. The antiviral effect was tested against Herpes simplex virus type 1 and 2, Poliovirus 1, Adenovirus 2, Echovirus 9, Coxsackievirus B1 through the plaque reduction assay. The antibacterial and antifungal activities were evaluated against medically important strains, by the microdilution method.
  • 928
  • 23 Jun 2021
Topic Review
Tackling Drug-Resistant Tuberculosis
Antibiotics have played a crucial role in the reduction in the incidence of tuberculosis (TB) globally as evidenced by the fact that before the mid-20th century, the mortality rate within five years of the onset of the disease was 50%. The use of antibiotics has eliminated TB as a devastating disease, but the challenge of resistance to anti-TB drugs, which had already been described at the time of the introduction of streptomycin, has become a major global issue in disease management. 
  • 928
  • 20 Sep 2023
Topic Review
Pseudomonas aeruginosa Metallophores
The human pathogen Pseudomonas aeruginosa (P. aeruginosa) causes several infections, both acute and chronic, mainly in hosts with compromised immunity and in patients suffering from cystic fibrosis. The pathogenesis of this bacterium is caused by several factors.
  • 927
  • 30 Nov 2022
Topic Review
Antibiotic Bacterial Resistance
Antibiotics are the main treatment against bacterial infections in animals and plants. As explained before, efficacy loss is known as antibiotic resistance; this manifestation occurs when bacteria mutate in response to excess and sublethal doses of these drugs. Antibiotic resistance is usually classified into intrinsic and acquired resistance. The first one is constitutive of each species, which means that each generation will present it. In contrast, the acquired mechanism occurs when bacteria obtain resistance genes through conjugation, transformation, transduction, and transposition. Regardless of the type of resistance, both cause this problem.
  • 927
  • 18 Jan 2023
Topic Review
Microorganisms and Climate Change
Climate variations directly impacts on the primary productive sectors, such as agriculture, forestry, livestock, and commercial fishing, which present the subsequent economic relevance. As a result, the effect of climate change has been widely discussed for years on flora and fauna. However, the aftermath evaluation over the worldwide microbiota is a challenging task poorly considered, up to date. In fact, most of these effects have yet to be quantified, but the proliferation and geographycally spread of pathogens of plants, animals, or humans are providing clues of the possible results. These microbial issues should be kept in mind and are the core of this entry.
  • 926
  • 02 Jan 2024
Topic Review
Bacterial Amelioration of Plant Drought and Salt Stress
Soil bacteria can express different plant-beneficial activities, inoculation of plants with one or more non-antagonistic microorganisms, belonging to the same or different species, or including both prokaryotic and eukaryotic organisms, can often facilitate plant growth. In fact, the lack of one plant beneficial activity in one strain can sometimes be overcome if another microorganism expresses this specific physiological trait. Moreover, the combination of diverse plant growth-promoting microorganisms (PGPM) offers a wide range of positive activity to a plant, including the enhancement of plant growth, reduced susceptibility to soil-borne diseases, increased yield, and improved seed and fruit nutritional value.
  • 925
  • 17 Mar 2022
Topic Review
Caenorhabditis elegans as an In Vivo Model
Antimicrobial resistance (AMR) due to the prevalence of multidrug-resistant (MDR) pathogens is rapidly increasing worldwide, and the identification of new antimicrobial agents with innovative mechanisms of action is urgently required. Medicinal plants that have been utilised for centuries with minor side effects may hold great promise as sources of effective antimicrobial products. The free-living nematode Caenorhabditis elegans (C. elegans) is an excellent live infection model for the discovery and development of new antimicrobial compounds. However, while C. elegans has widely been utilised to explore the effectiveness and toxicity of synthetic antibiotics, it has not been used to a comparable extent for the analysis of natural products.
  • 925
  • 11 Aug 2023
Topic Review
Environment, Gut Microbiota, and CAD
Gut microbiota has been shown to affect the cardiovascular system through different mechanisms, representing a potentially modifiable risk factor for atherosclerosis. This opens new perspectives on therapeutic and preventive strategies for coronary artery disease (CAD). Gut microbiota strongly varies depending on several environmental and lifestyle factors, such as pollution and diet, and maintains a symbiotic relationship with the gut mucosa, with substantial metabolic, immunological, and gut protective functions in the healthy individual.
  • 923
  • 23 Jun 2021
Topic Review
Antimicrobial-Resistant Bacteria and Genes in Fermented Foods
Fermented food products are widely consumed for their nutritional and health-promoting properties, earning them a central place in diets around the globe. However, these foods can present a paradox, as they have the potential to harbor not only beneficial probiotics but also antibiotic-resistant (AR) microbes and genes. The impact of AR microbes and genes in fermented foods has far-reaching implications, such as potential effects on human health, repercussions in the food industry, and environmental consequences. 
  • 922
  • 31 Jul 2023
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