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Toxins Sep 2021is a clinically important pathogen that causes a wide range of human infections, from minor skin infections to severe tissue infection and sepsis. has a high level of... (Review)
Review
is a clinically important pathogen that causes a wide range of human infections, from minor skin infections to severe tissue infection and sepsis. has a high level of antibiotic resistance and is a common cause of infections in hospitals and the community. The rising prevalence of community-acquired methicillin-resistant (CA-MRSA), combined with the important severity of infections in general, has resulted in the frequent use of anti-staphylococcal antibiotics, leading to increasing resistance rates. Antibiotic-resistant continues to be a major health concern, necessitating the development of novel therapeutic strategies. uses a wide range of virulence factors, such as toxins, to develop an infection in the host. Recently, anti-virulence treatments that directly or indirectly neutralize toxins have showed promise. In this review, we provide an update on toxin pathogenic characteristics, as well as anti-toxin therapeutical strategies.
Topics: Anti-Bacterial Agents; Staphylococcus aureus; Toxins, Biological; Virulence; Virulence Factors
PubMed: 34678970
DOI: 10.3390/toxins13100677 -
PLoS Pathogens Oct 2020First described in 2009 in Japan, the emerging multidrug-resistant fungal pathogen Candida auris is becoming a worldwide public health threat that has been attracting... (Review)
Review
First described in 2009 in Japan, the emerging multidrug-resistant fungal pathogen Candida auris is becoming a worldwide public health threat that has been attracting considerable attention due to its rapid and widespread emergence over the past decade. The reasons behind the recent emergence of this fungus remain a mystery to date. Genetic analyses indicate that this fungal pathogen emerged simultaneously in several different continents, where 5 genetically distinct clades of C. auris were isolated from distinct geographical locations. Although C. auris belongs to the CTG clade (its constituent species translate the CTG codon as serine instead of leucine, as in the standard code), C. auris is a haploid fungal species that is more closely related to the haploid and often multidrug-resistant species Candida haemulonii and Candida lusitaniae and is distantly related to the diploid and clinically common fungal pathogens Candida albicans and Candida tropicalis. Infections and outbreaks caused by C. auris in hospitals settings have been rising over the past several years. Difficulty in its identification, multidrug resistance properties, evolution of virulence factors, associated high mortality rates in patients, and long-term survival on surfaces in the environment make C. auris particularly problematic in clinical settings. Here, we review progress made over the past decade on the biological and clinical aspects of C. auris. Future efforts should be directed toward understanding the mechanistic details of its biology, epidemiology, antifungal resistance, and pathogenesis with a goal of developing novel tools and methods for the prevention, diagnosis, and treatment of C. auris infections.
Topics: Antifungal Agents; Candida; Candidiasis; Drug Resistance, Fungal; Humans; Saccharomycetales; Virulence
PubMed: 33091071
DOI: 10.1371/journal.ppat.1008921 -
Infection, Genetics and Evolution :... Apr 2021Cryptococcus neoformans is a dimorphic fungus that causes lethal meningoencephalitis mainly in immunocompromised individuals. Different morphotypes enable this... (Review)
Review
Cryptococcus neoformans is a dimorphic fungus that causes lethal meningoencephalitis mainly in immunocompromised individuals. Different morphotypes enable this environmental fungus and opportunistic pathogen to adapt to different natural niches and exhibit different levels of pathogenicity in various hosts. It is well-recognized that C. neoformans undergoes bisexual or unisexual reproduction in vitro to generate genotypic, morphotypic, and phenotypic diversity, which augments its ability for adaptation. However, if and how sexual reproduction and the meiotic machinery exert any direct impact on the infection process is unclear. This review summarizes recent discoveries on the regulation of cryptococcal life cycle and morphogenesis, and how they impact cryptococcal pathogenicity. The potential role of the meiotic machinery on ploidy regulation during cryptococcal infection is also discussed. This review aims to stimulate further investigation on links between fungal morphogenesis, sexual reproduction, and virulence.
Topics: Cryptococcus neoformans; Humans; Morphogenesis; Reproduction; Virulence
PubMed: 33497839
DOI: 10.1016/j.meegid.2021.104731 -
Microbial Pathogenesis May 2022Cryptococcus neoformans is an encapsulated fungal pathogen that causes infection in immunocompromised individuals such as HIV patients, organ transplant patients,... (Review)
Review
Cryptococcus neoformans is an encapsulated fungal pathogen that causes infection in immunocompromised individuals such as HIV patients, organ transplant patients, hematological malignancies, diabetes patients, etc. The most common invasive fungal pathogens are Candida spp., Aspergillus spp., and Cryptococcus spp. Cryptococcal meningitis has become increasingly common in immunocompromised patients resulting in a death rate of up to 90%. In low-income and middle-income countries, C. neoformans is a neglected killer in most parts of the world. It has unique and complicated virulence factors that facilitate its intracellular survival and dissemination. The initial infection, latency, or dissemination of the pathogen is determined by its specific morphological features such as capsule size, melanin pigment, biofilm development, etc. In this review, we discussed the worldwide distribution, classification of Cryptococcus spp., and a major focus on the pathogen's strategies that allow it to survive, proliferate subsequently disseminate resulting in cellular damage and treatment.
Topics: Cryptococcosis; Cryptococcus neoformans; HIV Infections; Humans; Virulence; Virulence Factors
PubMed: 35436563
DOI: 10.1016/j.micpath.2022.105521 -
Microbiology and Molecular Biology... Nov 2019is a highly versatile pathogen capable of causing infections in a wide range of domestic and wild animals as well as in humans and nonhuman primates. Despite over... (Review)
Review
is a highly versatile pathogen capable of causing infections in a wide range of domestic and wild animals as well as in humans and nonhuman primates. Despite over 135 years of research, the molecular basis for the myriad manifestations of pathogenesis and the determinants of phylogeny remain poorly defined. The current availability of multiple genome sequences now makes it possible to delve into the underlying genetic mechanisms of fitness and virulence. Using whole-genome sequences, the genotypes, including the capsular genotypes, lipopolysaccharide (LPS) genotypes, and multilocus sequence types, as well as virulence factor-encoding genes of isolates from different clinical presentations can be characterized rapidly and accurately. Putative genetic factors that contribute to virulence, fitness, host specificity, and disease predilection can also be identified through comparative genome analysis of different isolates. However, although some knowledge about genotypes, fitness, and pathogenesis has been gained from the recent whole-genome sequencing and comparative analysis studies of , there is still a long way to go before we fully understand the pathogenic mechanisms of this important zoonotic pathogen. The quality of several available genome sequences is low, as they are assemblies with relatively low coverage, and genomes of isolates from some uncommon host species are still limited or lacking. Here, we review recent advances, as well as continuing knowledge gaps, in our understanding of determinants contributing to virulence, fitness, host specificity, disease predilection, and phylogeny of .
Topics: Animals; Genetic Variation; Genome, Bacterial; Genomics; Genotype; Host Specificity; Humans; Pasteurella Infections; Pasteurella multocida; Phylogeny; Virulence; Virulence Factors
PubMed: 31484691
DOI: 10.1128/MMBR.00014-19 -
International Journal of Molecular... Jul 2020Microbial virulence factors encompass a wide range of molecules produced by pathogenic microorganisms, enhancing their ability to evade their host defenses and cause...
Microbial virulence factors encompass a wide range of molecules produced by pathogenic microorganisms, enhancing their ability to evade their host defenses and cause disease [...].
Topics: Bacteria; Humans; Virulence; Virulence Factors
PubMed: 32727013
DOI: 10.3390/ijms21155320 -
Virulence Dec 2024The genus includes human, animal, insect, and plant pathogens as well as many symbionts and harmless bacteria. Within this genus are and the complex, with four human... (Review)
Review
The genus includes human, animal, insect, and plant pathogens as well as many symbionts and harmless bacteria. Within this genus are and the complex, with four human pathogenic species that are highly related at the genomic level including the causative agent of plague, . Extensive laboratory, field work, and clinical research have been conducted to understand the underlying pathogenesis and zoonotic transmission of these pathogens. There are presently more than 500 whole genome sequences from which an evolutionary footprint can be developed that details shared and unique virulence properties. Whereas the virulence of now seems in apparent homoeostasis within its flea transmission cycle, substantial evolutionary changes that affect transmission and disease severity continue to ndergo apparent selective pressure within the other that cause intestinal diseases. In this review, we will summarize the present understanding of the virulence and pathogenesis of , highlighting shared mechanisms of virulence and the differences that determine the infection niche and disease severity.
Topics: Animals; Humans; Yersinia; Virulence; Yersinia pestis; Plague; Yersinia Infections
PubMed: 38389313
DOI: 10.1080/21505594.2024.2316439 -
Cellular Microbiology May 2021Cell adhesion molecules mediate cell-to-cell and cell-to-matrix adhesions and play an immense role in a myriad of physiological processes during the growth and... (Review)
Review
Cell adhesion molecules mediate cell-to-cell and cell-to-matrix adhesions and play an immense role in a myriad of physiological processes during the growth and development of a multicellular organism. Cadherins belong to a major group of membrane-bound cell surface proteins that, in coordination with nectins, drive the formation and maintenance of adherens junctions for mediating cell to cell adhesion, cellular communication and signalling. Alongside adhesive function, the involvement of cadherins in mediating host-pathogen interactions has been extensively explored in recent years. In this review, we provide an in-depth understanding of microbial pathogens and their virulence factors that exploit cadherins for their strategical invasion into the host cell. Furthermore, macromolecular interactions involving cadherins and various microbial factors such as secretory toxins and adhesins lead to the disintegration of host cell junctions followed by the entry of the pathogen or triggering downstream signalling pathways responsible for successful invasion of the pathogenic microbes are discussed. Besides providing a comprehensive insight into some of the structural complexes involving cadherins and microbial factors to offer the mechanistic details of host-pathogen interactions, the current review also highlights novel constituents of various cell signalling events such as endocytosis machinery elicited upon microbial infections.
Topics: Animals; Bacteria; Bacterial Infections; Cadherins; Endocytosis; Fungi; Host-Pathogen Interactions; Humans; Mycoses; Signal Transduction; Virulence; Virulence Factors; Virus Diseases; Viruses
PubMed: 33543826
DOI: 10.1111/cmi.13316 -
Annals of the New York Academy of... Sep 2022Staphylococcus aureus is a pathobiont capable of colonizing and infecting most tissues within the human body, resulting in a multitude of different clinical outcomes.... (Review)
Review
Staphylococcus aureus is a pathobiont capable of colonizing and infecting most tissues within the human body, resulting in a multitude of different clinical outcomes. Adhesion of S. aureus to the host is crucial for both host colonization and the establishment of infections. Underlying the pathogen's success is a complex and diverse arsenal of adhesins. In this review, we discuss the different classes of adhesins, including a consideration of the various adhesion sites throughout the body and the clinical outcomes of each infection type. The development of therapeutics targeting the S. aureus host-pathogen interaction is a relatively understudied area. Due to the increasing global threat of antimicrobial resistance, it is crucial that innovative and alternative approaches are considered. Neutralizing virulence factors, through the development of antivirulence agents, could reduce bacterial pathogenicity and the ever-increasing burden of S. aureus infections. This review provides insight into potentially efficacious adhesion-associated targets for the development of novel decolonizing and antivirulence strategies.
Topics: Anti-Infective Agents; Humans; Staphylococcal Infections; Staphylococcus aureus; Virulence; Virulence Factors
PubMed: 35705378
DOI: 10.1111/nyas.14807 -
Advances in Microbial Physiology 2022AB toxins are protein virulence factors secreted by many bacterial pathogens, contributing to the pathogenicity of the cognate bacteria. AB toxins consist of two... (Review)
Review
AB toxins are protein virulence factors secreted by many bacterial pathogens, contributing to the pathogenicity of the cognate bacteria. AB toxins consist of two functionally distinct components: the enzymatic "A" component for pathogenicity and the receptor-binding "B" component for toxin delivery. Consistently, unlike other virulence factors such as effectors, AB toxins do not require additional systems to deliver them to the target host cells. Target host cells are located in the infection site and/or located distantly from infected host cells. The first part of this review discusses the structural and functional features of single-peptide and multiprotein AB toxins in the context of host-microbe interactions, using several well-characterized examples. The second part of this review discusses toxin neutralization strategies, as well as applications of AB toxins relevant to developing intervention strategies against diseases.
Topics: Bacteria; Bacterial Toxins; Host Microbial Interactions; Virulence; Virulence Factors
PubMed: 36167443
DOI: 10.1016/bs.ampbs.2022.06.002