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Topic Review
Attenuated Vaccine
An attenuated vaccine (or a live attenuated vaccine, LAV) is a vaccine created by reducing the virulence of a pathogen, but still keeping it viable (or "live"). Attenuation takes an infectious agent and alters it so that it becomes harmless or less virulent. These vaccines contrast to those produced by "killing" the virus (inactivated vaccine). Attenuated vaccines stimulate a strong and effective immune response that is long-lasting. In comparison to inactivated vaccines, attenuated vaccines produce a stronger and more durable immune response with a quick immunity onset. Attenuated vaccines function by encouraging the body to create antibodies and memory immune cells in response to the specific pathogen which the vaccine protects against. Common examples of live attenuated vaccines are measles, mumps, rubella, yellow fever, and some influenza vaccines.
  • 1.9K
  • 01 Dec 2022
Topic Review
Genetic Engineering of Actinomycetes
The first antibiotic-producing actinomycete (Streptomyces antibioticus) was described by Waksman and Woodruff in 1940. This discovery initiated the “actinomycetes era”, in which several species were identified and demonstrated to be a great source of bioactive compounds. However, the remarkable group of microorganisms and their potential for the production of bioactive agents were only partially exploited. This is caused by the fact that the growth of many actinomycetes cannot be reproduced on artificial media at laboratory conditions. In addition, sequencing, genome mining and bioactivity screening disclosed that numerous biosynthetic gene clusters (BGCs), encoded in actinomycetes genomes are not expressed and thus, the respective potential products remain uncharacterized. Therefore, a lot of effort was put into the development of technologies that facilitate the access to actinomycetes genomes and activation of their biosynthetic pathways. In this review  (Antibiotics 2020, 9(8), 494; https://doi.org/10.3390/antibiotics9080494), we mainly focus on molecular tools and methods for genetic engineering of actinomycetes that have emerged in the field in the past five years (2015–2020). In addition, we highlight examples of successful application of the recently developed technologies in genetic engineering of actinomycetes for activation and/or improvement of the biosynthesis of secondary metabolites.
  • 1.9K
  • 28 Dec 2020
Topic Review
Postbiotics and Kidney Disease
Chronic kidney disease (CKD) is projected to become the fifth global cause of death by 2040 as a result of key shortcomings in the current methods available to diagnose and treat kidney diseases. In this regard, the novel holobiont concept, used to describe an individual host and its microbial community, may pave the way towards a better understanding of kidney disease pathogenesis and progression. Microbiota-modulating or -derived interventions include probiotics, prebiotics, synbiotics and postbiotics.
  • 1.9K
  • 13 Oct 2022
Topic Review
Promising Lead Compounds for Resistant-Tuberculosis
According to WHO report, globally about 10 million active tuberculosis cases, resulting in about 1.6 million deaths, further aggravated by drug-resistant tuberculosis and/or comorbidities. Incomplete therapeutic regimen, meager dosing, and the capability of the latent and/or active state tubercular bacilli to abide and do survive against contemporary first-line and second-line antitubercular drugs escalate the prevalence of drug-resistant tuberculosis. To explore and identify the most potential antitubercular drug candidate among various reported compounds, here we focused to highlight the promising lead derivatives of isoniazid, coumarin, griselimycin, and antimicrobial peptides. The aim of the present review is to fascinate significant lead compounds in the development of potential clinical drug candidates that might be more precise and effective against drug-resistant tuberculosis, the world research looking for a long time.
  • 1.9K
  • 10 Dec 2020
Topic Review
PirAB from Vibrio parahaemolyticus and AHPND in Shrimp
PirAB is a potent toxin which can causes 100% mortality in shrimp, the toxin produce masive sloughing of the epithelial cells of the shrimp hepatopancreas, kown as acute hepatopancreatic necrosis diseaseas (AHPND) in diseased penaeid shirmp. This toxin is produced by specific strains of Vibrio parahaemolyticus, which harbors a plasmid of ~70 kbp (pVA1) containing the pirAVp and pirBVp genes that encode PirAB toxin.   
  • 1.9K
  • 20 Apr 2022
Topic Review
Brettanomyces bruxellensis
The Brettanomyces bruxellensis species plays various roles in both the industrial and food sectors. At the biotechnological level, B. bruxellensis is considered to be a promising species for biofuel production. Its presence in alcoholic beverages can be detrimental or beneficial to the final product; B. bruxellensis can contribute to spoilage of wine and beer, but can also produce good aromas.
  • 1.9K
  • 31 Aug 2021
Topic Review
Cellular Communication
Cellular communication is an umbrella term used in biology and more in depth in biophysics, biochemistry and biosemiotics to identify different types of communication methods between living cellulites. Some of the methods include cell signaling among others. This process allows millions of cells to communicate and work together to perform important bodily processes that are necessary for survival. Both multicellular and unicellular organisms heavily rely on cell-cell communication.
  • 1.9K
  • 24 Oct 2022
Topic Review
Leishmaniases
The control of leishmaniases, a complex parasitic disease caused by the protozoan parasite Leishmania, requires continuous innovation at the therapeutic and vaccine levels. Thus, the classical drugs are toxic and generate drug resistance. These limitations are also the consequence of a non adapted biodistribution of the active principles. Chitosan is a biocompatible polymer administrable via different routes and possessing numerous qualities to be used in the antileishmanial strategies.
  • 1.9K
  • 27 Oct 2020
Topic Review
Quorum Sensing Regulation
Quorum sensing is a type of chemical communication by which bacterial populations control expression of their genes in a coordinated manner. This regulatory mechanism is commonly used by pathogens to control the expression of genes encoding virulence factors and that of genes involved in the bacterial adaptation to variations in environmental conditions. In phytopathogenic bacteria, several mechanisms of quorum sensing have been characterized. In this review, we describe the different quorum sensing systems present in phytopathogenic bacteria, such as those using the signal molecules named N-acyl-homoserine lactone (AHL), diffusible signal factor (DSF), and the unknown signal molecule of the virulence factor modulating (VFM) system. We focus on studies performed on phytopathogenic bacteria of major importance, including Pseudomonas, Ralstonia, Agrobacterium, Xanthomonas, Erwinia, Xylella,Dickeya, and Pectobacterium spp. For each system, we present the mechanism of regulation, the functions targeted by the quorum sensing system, and the mechanisms by which quorum sensing is regulated.
  • 1.9K
  • 05 Mar 2021
Topic Review
The Biological Activities of Marine Exopolysaccharides
The unique living environment of marine microorganisms endows them with the potential to produce novel compounds with diverse biological activities. Exopolysaccharide (EPS) is a high molecular weight carbohydrate polymer secreted by microorganisms during growth and metabolism. The complex and diverse structures of EPS endow them with unique biological activities and functions. 
  • 1.9K
  • 23 Aug 2022
Topic Review
Bacteriologist (Professional)
A bacteriologist is a professional trained in bacteriology, a subdivision of microbiology. The duties of a bacteriologist include prevention, diagnosis and prognosis of diseases, as well as health care, and they may carry out various functions such as epidemiological surveillance, quality auditing with biotechnology development, basic research, management and teaching related to the career, scientist management, laboratory coordination and blood banks.
  • 1.9K
  • 03 Nov 2022
Topic Review
Plant Host Defense Peptides: Snakins
Plant host defense peptides (HDPs), also known as antimicrobial peptides (AMPs), are regarded as one of the most prevalent barriers elaborated by plants to combat various infective agents. HDPs are arbitrarily referred to as small, thermal stable, and positively charged peptides, generally comprising peptides of less than 100 amino acid residues with an overall net charge of +2 to +9, and molecular weight of 4 to 9 kDa. Plant HDPs can be classified into at least eight major families, including defensins, thionins, non-specific lipid-transfer proteins (LTPs), hevein-like peptides, Snakins, knottins, α-hairpinins, and cyclotides, among which the Snakin family peptide has been reported to be the most abundant potential AMP that is active against fungal and bacterial pathogens. The Snakin/GASA family peptides consist of 12 cysteine residues, being the foremost cysteine-rich peptides among different classes of plant HDPs.
  • 1.9K
  • 01 Apr 2021
Topic Review
Campylobacter Jejuni
Campylobacter jejuni (/ˈkæmpɪloʊˌbæktər dʒəˈdʒuːni/) is one of the most common causes of food poisoning in Europe and in the United States. The vast majority of cases occur as isolated events, not as part of recognized outbreaks. Active surveillance through the Foodborne Diseases Active Surveillance Network (FoodNet) indicates that about 20 cases are diagnosed each year for each 100,000 people in the US, while many more cases are undiagnosed or unreported; the CDC estimates a total of 1.5 million infections every year. The European Food Safety Authority reported 246,571 cases in 2018, and estimated approximately nine million cases of human campylobacteriosis per year in the European Union. Campylobacter jejuni is in a genus of bacteria that is among the most common causes of bacterial infections in humans worldwide. Campylobacter means "curved rod", deriving from the Greek kampylos (curved) and baktron (rod). Of its many species, C. jejuni is considered one of the most important from both a microbiological and public health perspective. C. jejuni is commonly associated with poultry, and is also commonly found in animal feces. Campylobacter is a helical-shaped, non-spore-forming, Gram-negative, microaerophilic, nonfermenting motile bacterium with a single flagellum at one or both poles, which are also oxidase-positive and grow optimally at 37 to 42 °C. When exposed to atmospheric oxygen, C. jejuni is able to change into a coccal form. This species of pathogenic bacteria is one of the most common causes of human gastroenteritis in the world. Food poisoning caused by Campylobacter species can be severely debilitating, but is rarely life-threatening. It has been linked with subsequent development of Guillain–Barré syndrome, which usually develops two to three weeks after the initial illness. Individuals with recent C. jejuni infections develop Guillain-Barré syndrome at a rate of 0.3 per 1000 infections, about 100 times more often than the general population. Another chronic condition that may be associated with Campylobacter infection is reactive arthritis. Reactive arthritis is a complication strongly associated with a particular genetic make-up. That is, persons who have the human leukocyte antigen B27 (HLA-B27) are most susceptible. Most often, the symptoms of reactive arthritis will occur up to several weeks after infection.
  • 1.9K
  • 10 Nov 2022
Topic Review
SV40
SV40 is an abbreviation for simian vacuolating virus 40 or simian virus 40, a polyomavirus that is found in both monkeys and humans. Like other polyomaviruses, SV40 is a DNA virus that has the potential to cause tumors in animals, but most often persists as a latent infection. SV40 has been widely studied as a model eukaryotic virus, leading to many early discoveries in eukaryotic DNA replication and transcription.
  • 1.9K
  • 26 Oct 2022
Topic Review
Meningococcal Disease
Meningococcal disease describes infections caused by the bacterium Neisseria meningitidis (also termed meningococcus). It has a high mortality rate if untreated but is vaccine-preventable. While best known as a cause of meningitis, it can also result in sepsis, which is an even more damaging and dangerous condition. Meningitis and meningococcemia are major causes of illness, death, and disability in both developed and under-developed countries. There are approximately 2,600 cases of bacterial meningitis per year in the United States, and on average 333,000 cases in developing countries. The case fatality rate ranges between 10 and 20 percent. The incidence of endemic meningococcal disease during the last 13 years ranges from 1 to 5 per 100,000 in developed countries, and from 10 to 25 per 100,000 in developing countries. During epidemics the incidence of meningococcal disease approaches 100 per 100,000. Meningococcal vaccines have sharply reduced the incidence of the disease in developed countries. The disease's pathogenesis is not fully understood. Neisseria meningitidis colonises a substantial proportion of the general population harmlessly, but in a very small percentage of individuals it can invade the bloodstream, affecting the entire body, most notably limbs and brain, causing serious illness. Over the past few years, experts have made an intensive effort to understand specific aspects of meningococcal biology and host interactions; however, the development of improved treatments and effective vaccines is expected to depend on novel efforts by workers in many different fields. While meningococcal disease is not as contagious as the common cold (which is spread through casual contact), it can be transmitted through saliva and occasionally through close, prolonged general contact with an infected person.
  • 1.9K
  • 10 Oct 2022
Topic Review
The Microbiome in Obesity
Obesity has become a global epidemic and a public health crisis in the Western World, experiencing a threefold increase in prevalence since 1975. High-caloric diets and sedentary lifestyles have been identified as significant contributors to this widespread issue, although the role of genetic, social, and environmental factors in obesity’s pathogenesis remain incompletely understood. In recent years, much attention has been drawn to the contribution of the gut microbiota in the development of obesity, driven by a body of evidence supporting its central role in regulation of host physiology. Indeed, research has shown that in contrast to their healthier counterparts the microbiomes of obese individuals are structurally and functionally distinct, strongly suggesting gut dysbiosis as a key factor underpinning an obese phenotype. The following entry  explores the myriad of mechanisms by which the microbiome may contribute to the etiology of obesity, including modulation of host energy balance, immune function and macronutrient metabolism. 
  • 1.8K
  • 04 May 2021
Topic Review
COVID-19-Associated Candidiasis
The recent global pandemic of COVID-19 has predisposed a relatively high number of patients to acute respiratory distress syndrome (ARDS), which carries a risk to develop secondary infections. Candida species are major constituents of the human mycobiome and the main cause of invasive fungal infections with a high mortality rate, and are also increasingly reported as complication of severe COVID-19. Despite the marked immune dysregulation in COVID-19, no prominent defects have been reported in immune cells that are critically required for immunity to Candida. This suggests that relevant clinical factors, including prolonged ICU stays, use of central venous catheters and often broad-spectrum antibiotics may dominate over immune-mediated mechanisms to drive susceptibility to candidemia in the setting of COVID-19. Although diagnostic performance evaluations are often lacking in COVID-19 patients, a combination of serological and molecular techniques may present promising diagnostic options for identification of COVID-19-associated candidiasis. Clinical awareness and screening of invasive candidiasis is needed, as those are difficult to diagnose, particular in the setting of severe COVID-19. Echinocandins and azoles are the primary antifungal used to treat invasive candidiasis, yet therapeutic failures exerted by prominent nosocomial pathogens such as C. auris and C. glabrata calls for the development of new antifungal drugs with novel mechanisms of action.
  • 1.8K
  • 26 Oct 2020
Topic Review
New Carbapenemase Inhibitors
Carbapenem resistance is a major global health problem that seriously compromises the treatment of infections caused by nosocomial pathogens. Production of carbapenemases (carbapenem-hydrolyzing enzymes) is the most important mechanism of carbapenem resistance. A new generation of promising carbapenemase inhibitors, together with the recently approved avibactam, relebactam and vaborbactam are being tested in clinical and pre-clinical trials.This review summarizes the main, most promising carbapenemase inhibitors synthesized to date. 
  • 1.8K
  • 30 Dec 2020
Topic Review
Flagellum/Stigma in Euglena gracilis
Cell division of unicellular microalgae is a fascinating process of proliferation, at which whole organelles are regenerated and distributed to two new lives. We performed dynamic live cell imaging of Euglena gracilis using optical microscopy to elucidate the mechanisms involved in the regulation of the eyespot and flagellum during cell division and distribution of the organelles into the two daughter cells. Single cells of the wild type (WT) and colorless SM-ZK cells were confined in a microfluidic device, and the appearance of the eyespot (stigma) and emergent flagellum was tracked in sequential video-recorded images obtained by automatic cell tracking and focusing. We examined 12 SM-ZK and 10 WT cells and deduced that the eyespot diminished in size and disappeared at an early stage of cell division and remained undetected for 26–97 min (62 min on average, 22 min in deviation). Subsequently, two small eyespots appeared and were distributed into the two daughter cells. Additionally, the emergent flagellum gradually shortened to zero-length, and two flagella emerged from the anterior ends of the daughter cells. Our observation revealed that the eyespot and flagellum of E. gracilis are degraded once in the cell division, and the carotenoids in the eyespot are also decomposed. Subsequently, the two eyespots/flagella are regenerated for distribution into daughter cells. As a logical conclusion, the two daughter cells generated from a single cell division possess the equivalent organelles and each E. gracilis cell has eternal or non-finite life span. The two newly regenerated eyespot and flagellum grow at different rates and mature at different timings in the two daughter cells, resulting in diverse cell characteristics in E. gracilis.
  • 1.8K
  • 05 Nov 2021
Topic Review
Salmonella enterica Outbreaks from Tahini and Tahini-Based Products
Salmonella is a leading cause of bacterial foodborne illness in the world. Although typically associated with foods of animal origin, low-moisture foods, such as tahini, are quickly gaining recognition as an important vehicle of Salmonella exposure.
  • 1.8K
  • 05 Dec 2022
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