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Topic Review
Biogenic amines in Fish
The occurrence of biogenic amines in fish is directly associated with microorganisms with decarboxylase activity. These compounds are generally detoxified by oxidases in the intestinal tract of humans, but some conditions, such as alcohol consumption, enzyme deficiency, or monoamino-oxidase antidepressant use, can make their intake by food dangerous. Due to its toxicity, histamine is a unique biogenic amine with regulatory limits for fishery products. This review focuses on biogenic amines in fish, with a detailed picture of the number of alert notifications or intoxication events reported in the last years. The favoring conditions for their formation, as well as the main preventive and control measures to ensure public health, are also reviewed.
  • 2.8K
  • 18 Dec 2020
Topic Review
Escherichia coli Shiga Toxins
Escherichia coli (EHEC) and Shigella dysenteriae serotype 1 are enterohemorrhagic bacteria that induce hemorrhagic colitis. This, in turn, may result in potentially lethal complications, such as hemolytic uremic syndrome (HUS), which is characterized by thrombocytopenia, acute renal failure, and neurological abnormalities. Both species of bacteria produce Shiga toxins (Stxs), a phage-encoded exotoxin inhibiting protein synthesis in host cells that are primarily responsible for bacterial virulence.
  • 2.7K
  • 23 Jun 2021
Topic Review
Fungal Proteases
Proteases are obtained from plants, animals, and microorganisms. Plants and animals’ proteases are more complex as compared to microorganisms. Fungal proteases are used as detergents for the removal of stains by hydrolyzing the peptide bond among the protein molecules.
  • 2.7K
  • 14 Mar 2022
Topic Review
Haemophilus Influenzae
Haemophilus influenzae (formerly called Pfeiffer's bacillus or Bacillus influenzae) is a Gram-negative, coccobacillary, facultatively anaerobic capnophilic pathogenic bacterium of the family Pasteurellaceae. The bacterium was argued by some to be the cause of influenza. H. influenzae was first described in 1892 by Richard Pfeiffer during an influenza pandemic when he incorrectly described Haemophilus influenzae as the causative microbe, which explains why the bacteria retains "influenza" in its name. H. influenzae is responsible for a wide range of localized and invasive infections, but influenza is caused by viruses. This species was the first free-living organism to have its entire genome sequenced.
  • 2.7K
  • 23 Nov 2022
Topic Review
Chloroflexi (Phylum)
The Chloroflexi or Chlorobacteria are a phylum of bacteria containing isolates with a diversity of phenotypes, including members that are aerobic thermophiles, which use oxygen and grow well in high temperatures; anoxygenic phototrophs, which use light for photosynthesis (green non-sulfur bacteria); and anaerobic halorespirers, which uses halogenated organics (such as the toxic chlorinated ethenes and polychlorinated biphenyls) as electron acceptors. Most bacteria, in terms of diversity, are diderms and stain gram-negative, notable exceptions being Firmicutes (low G+C gram-positives), Actinobacteria (high-G+C gram-positives) and the Deinococcus–Thermus group (gram-positive diderms with thick peptidoglycan). In contrast, the members of the phylum Chloroflexi are monoderms, but stain mostly gram-negative.
  • 2.7K
  • 21 Oct 2022
Topic Review
Human Cytomegalovirus
Human cytomegalovirus (HCMV) expresses a variety of viral regulatory proteins that undergo close interaction with host factors including viral-cellular multiprotein complexes. The HCMV protein kinase pUL97 represents a viral CDK ortholog (vCDK) that determines the efficiency of HCMV replication via phosphorylation of viral and cellular substrates. A hierarchy of functional importance of individual pUL97-mediated phosphorylation events has been discussed, however, the most pronounced pUL97-dependent phenotype could be assigned to viral nuclear egress, as illustrated by genetic ORF-UL97 deletion or pharmacological pUL97 inhibition. Despite earlier data pointing to a cyclin-independent functionality, experimental evidence increasingly emphasized the role of pUL97-cyclin complexes. Consequently, the knowledge about pUL97 involvement in host interaction, viral nuclear egress and additional replicative steps led to the postulation of pUL97 as an antiviral target. Indeed, validation experiments in vitro and in vivo confirmed the sustainability of this approach. Consequently, current investigations of pUL97 in antiviral treatment go beyond the known pUL97-mediated ganciclovir prodrug activation and henceforward include pUL97-specific kinase inhibitors. Among a number of interesting small molecules analyzed on experimental and preclinical stages, maribavir is presently investigated in clinical studies and, in the near future, might represent a first kinase inhibitor applied in the field of antiviral therapy.
  • 2.7K
  • 29 Oct 2020
Topic Review
Methanogens in industrial wastewater treatment
Anaerobic biotechnology is commonly used for treating high-strength wastewaters from different industries. Properties of wastewater vary across industries and significantly affect microbiome composition in the anaerobic reactor. Methanogenic archaea play a crucial role during anaerobic wastewater treatment.
  • 2.7K
  • 22 Jan 2021
Topic Review
Chasing the Elusive Luciferin
Regarding dinoflagellates, the mechanisms related to the bioluminescent phenomenon have been well studied; however, at present, some points that remain unknown still persist. That is the case of luciferin biosynthesis, which has been reported to be an intricate process with several metabolic pathways involved. In the context of this controversial scenario, various hypotheses about the biosynthesis of luciferin in dinoflagellates are presented.
  • 2.7K
  • 10 Dec 2020
Topic Review
PTMs Role During Virus Infection
Viruses are opportunistic intracellular pathogens that are dependent on the host for their replication. They hijack host cellular machinery for their replication and survival by targeting crucial cellular physiological pathways, including transcription, translation, immune pathways, and apoptosis. Immediately after translation, the host and viral proteins undergo a process called post-translational modification (PTM). PTMs of proteins involves the attachment of small proteins, carbohydrates/lipids, or chemical groups to the proteins and are crucial for protein's functioning. During viral infection, host proteins utilize PTMs to control the virus replication, using strategies like activating immune response pathways, inhibiting viral protein synthesis, and ultimately eliminating the virus from the host. PTM of viral proteins increases solubility, enhances antigenicity and virulence properties. However, RNA viruses are devoid of enzymes capable of introducing PTMs to their proteins. Hence, they utilize the host PTM machinery to promote their survival. Proteins from viruses belonging to the family: Togaviridae, Flaviviridae, Retroviridae, and Coronaviridae such as chikungunya, dengue, zika, HIV, and coronavirus are a few well-known to be modified. This review discusses various host and virus-mediated PTMs that play a role in the outcome during the infection.
  • 2.7K
  • 28 Jan 2021
Topic Review
Microorganisms
Microorganisms are a diverse group of microscopic organisms including archaea, bacteria, fungi, protozoa, algae, and viruses. Microbial diversity produces a massive pool of unique chemicals, which have become a valuable source for innovative biotechnology. About 23,000 secondary metabolites from microorganisms are known, out of which actinomycetes exclusively produce approximately 42%, whereas fungi form almost similar amounts (42%), and the remaining 16% is produced by eubacteria.
  • 2.7K
  • 27 Jan 2022
Topic Review
Antimicrobial photodynamic therapy (aPDT)
Photodynamic inactivation is known as a new antimicrobial photodynamic therapy (aPDT). It is based on the administration of a photosensitizer located in the bacterial/viral cell followed by exposure to light radiations (with a proper wavelength corresponding with the maximum value of absorption of the photosensitizer) that generate singlet oxygen or reactive oxygen species, which lead to the death of different microorganisms. This review will present an overview beyond the state-of-the-art of the photosensitizer types (based on tetra-p-sulphonated-phenyl porphyrin—TSPP, which is able to form cationic and J-aggregates forms at different pH values ((1–4) and concentrations around 10−5 M) and their applications of PDT for viruses, especially. 
  • 2.7K
  • 30 Sep 2021
Topic Review
Antimicrobial Resistance
The discovery of antibiotics has revolutionized the medicine and treatment of microbial infections. However, the current scenario has highlighted the difficulties in marketing new antibiotics and an exponential increase in the appearance of resistant strains. Here, the main antibiotic resistance mechanisms are briefly listed with some examples. 
  • 2.7K
  • 05 Nov 2020
Topic Review
Antimicrobial-resistance genes in human gut
Antibiotic-resistance has long been associated with the use and abuse of antibiotics. However, increasing evidence is suggesting that antibiotic-resistance is in fact a phenomenon that has been occurring in natural environments for thousands and possibly millions of years. With the expansion of the microbiome field, it is now possible to characterize antibiotic-resistance genes altogether in different samples, including the human gut. This has also enabled the characterization of ancient human gut microbiomes, which also include antibiotic-resistance genes. Mummified gut remains represent a unique opportunity to characterize the microbiome and antibiotic-resistance genes prior the antibiotic-therapy era. Surprisingly, mummies from the Inca and Italian nobility cultures showed to possess antibiotic-resistance-like genes similar to modern-day antibiotic-resistance genes conferring resistance to beta-lactams, sulfa, quinolones and vancomycin, just to mention a few examples. This is intriguing as it further supports that antibiotic-resistance began in the environment and was transferred to the human gut by means that remain to be investigated and are a matter of ongoing speculation.
  • 2.7K
  • 29 Oct 2020
Topic Review
Parvovirus
Parvovirus is the common name applied to all the viruses in the Parvoviridae taxonomic family. Parvovirus can also be used specifically for members of one of the two Parvoviridae subfamilies: Parvovirinae, which infect vertebrate hosts, and Densovirinae, which infect invertebrate hosts, are more commonly referred to as densoviruses. In subfamily Parvovirinae there are eight genera, containing a total of 58 recognized species, while in subfamily Densovirinae there are 5 genera and a total of 21 species. Parvoviruses are linear, nonsegmented, single-stranded DNA viruses, with an average genome size of 5-6 kilo base pairs (kbp). They are classified as group II viruses in the Baltimore classification of viruses. Parvoviruses are among the smallest viruses (hence the name, from Latin parvus meaning small) and are 23–28 nm in diameter. Parvoviruses can infect and may cause disease in many animals, from arthropods such as insects and shrimp, to echinoderms such as starfish, and to mammals including humans. Because most of these viruses require actively dividing cells to replicate, the type of tissue infected varies with the age of the animal. The gastrointestinal tract and lymphatic system can be affected at any age, leading to vomiting, diarrhea, and immunosuppression, but cerebellar hypoplasia is only seen in cats that were infected with feline parvovirus (FPV) in the womb or at less than two weeks of age, and disease of the myocardium is seen in puppies infected with canine parvovirus 2 (CPV2) between the ages of three and eight weeks.
  • 2.7K
  • 10 Oct 2022
Topic Review
Pathogenesis of Helicobacter pylori
Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the gastric mucosa and is associated with various gastrointestinal disorders. H. pylori is a pervasive pathogen, infecting nearly 50% of the world’s population, and presents a substantial concern due to its link with gastric cancer, ranking as the third most common cause of global cancer-related mortality. 
  • 2.6K
  • 07 Feb 2024
Topic Review
LABs and Silage Production
Lactic acid bacteria (LAB) are considered potent natural additives for animal feed production due to the efficient production of biological metabolites—notably, higher lactic acid content with marginal level acetic acid and other organic acids. Furthermore, LAB can utilize water-soluble carbohydrates and convert them into valuable organic acids, which increase the acidification of the surrounding environment. Rapid acidification (lower pH) could help to prevent undesirable microbial growth and toxic secondary metabolite secretion.
  • 2.6K
  • 07 Jan 2022
Topic Review
Antifungal Therapy
Antifungals (also referred to as antimycotics) are the type of antibiotics used to treat fungal infections. In contrast to bacteria, fungi are eukaryotic organisms; thus fungal cells are very similar to our own cells. Because of this there is a limited number of selective targets and the current arsenal of antifungal drugs is very limited, which contributes to high mortality rates. In addition, development of resistance against current antifungals poses additional challenges. Clearly, new antifungal agents are urgently needed. 
  • 2.6K
  • 22 Oct 2020
Topic Review
Lactoferrin and Lactobacilli
Vaginal infections are the most prevalent women's health problem. Incompetent diagnosis, inappropriate treatments, and antibiotic resistance are the main causes of the unsatisfactory results of conventional antimicrobic treatment for these infections. Consequently, several researches have been carried out to identify new treatments for these genital diseases. The significant enhancement in our knowledge of vaginal microbiota has permitted to develop new nonpharmacological strategies for the treatment of vaginal infections that seek to restore the balance of vaginal microflora, as opposed to modifying its components. Among these approaches, bioactive compounds, such as probiotics and nutraceutical proteins (like lactoferrin), deserve particular attention. The aim of this review is to examine the role of probiotics (mainly Lactobacillus spp.) and lactoferrin as new strategies for counteracting bacterial and fungal vaginal infections.
  • 2.6K
  • 30 Oct 2020
Topic Review
Planctomycetes
The Planctomycetes are a phylum of widely distributed bacteria, occurring in both aquatic and terrestrial habitats. They play a considerable role in global carbon and nitrogen cycles, with many species of this phylum capable of anaerobic ammonium oxidation, also known as anammox. Many planctomycetes occur in relatively high abundance as biofilms, often associating with other organisms such as macroalgae and marine sponges. Planctomycetes are included in the PVC superphylum along with Verrucomicrobia, Chlamydiae, Lentisphaerae, Kiritimatiellaeota, and Candidatus Omnitrophica. The phylum Planctomycete is composed of the classes Planctomycetia and Phycisphaerae. First described in 1924, members of the Planctomycetes were identified as eukaryotes and were only later described as bacteria in 1972. Early examination of members of the Planctomycetes suggested a cell plan differing considerably from other bacteria, although they are now confirmed as Gram-negative bacteria, but with many unique characteristics. Bacteria in the Planctomycetes are often small, spherical cells, but a large amount of morphological variation is seen. Members of the Planctomycetes also display distinct reproductive habits, with many species dividing by budding, in contrast to all other free-living bacteria, which divide by binary fission. Interest is growing in the Planctomycetes regarding biotechnology and human applications, mainly as a source of bioactive molecules. In addition, some Planctomycetes were recently described as human pathogens. The species Gemmata obscuriglobus has been identified specifically as comprising bacteria with unique characteristics among the Planctomycetes, such as their ability to synthesize sterols.
  • 2.6K
  • 16 Nov 2022
Topic Review
Secretion Systems of Acinetobacter baumannii
Infections led by Acinetobacter baumannii strains are of great concern in healthcare environments due to the strong ability of the bacteria to spread through different apparatuses and develop drug resistance. Secretion systems have recently been demonstrated to be involved in the pathogenic process, and five types of secretion systems out of the known six from Gram-negative bacteria have been found in A. baumannii. They can promote the fitness and pathogenesis of the bacteria by releasing a variety of effectors. Additionally, antibiotic resistance is found to be related to some types of secretion systems.
  • 2.6K
  • 02 Feb 2023
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