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Journal of Invertebrate Pathology Sep 2019The development of infectious diseases represents an outcome of dynamic interactions between the disease-producing agent's pathogenicity and the host's self-defense... (Review)
Review
The development of infectious diseases represents an outcome of dynamic interactions between the disease-producing agent's pathogenicity and the host's self-defense mechanism. Proteases secreted by pathogenic microorganisms and protease inhibitors produced by host species play an important role in the process. This review aimed at summarizing major findings in research on pathogen proteases and host protease inhibitors that had been proposed to be related to the development of mollusk diseases. Metalloproteases and serine proteases respectively belonging to Family M4 and Family S8 of the MEROPS system are among the most studied proteases that may function as virulence factors in mollusk pathogens. On the other hand, a mollusk-specific family (Family I84) of novel serine protease inhibitors and homologues of the tissue inhibitor of metalloprotease have been studied for their potential in the molluscan host defense. In addition, research at the genomic and transcriptomic levels showed that more proteases of pathogens and protease inhibitor of hosts are likely involved in mollusk disease processes. Therefore, the pathological significance of interactions between pathogen proteases and host protease inhibitors in the development of molluscan infectious diseases deserves more research efforts.
Topics: Animals; Host-Pathogen Interactions; Mollusca; Peptide Hydrolases; Virulence; Virulence Factors
PubMed: 31348922
DOI: 10.1016/j.jip.2019.107214 -
Nature Reviews. Microbiology Aug 2020Xanthomonas spp. encompass a wide range of plant pathogens that use numerous virulence factors for pathogenicity and fitness in plant hosts. In this Review, we examine... (Review)
Review
Xanthomonas spp. encompass a wide range of plant pathogens that use numerous virulence factors for pathogenicity and fitness in plant hosts. In this Review, we examine recent insights into host-pathogen co-evolution, diversity in Xanthomonas populations and host specificity of Xanthomonas spp. that have substantially improved our fundamental understanding of pathogen biology. We emphasize the virulence factors in xanthomonads, such as type III secreted effectors including transcription activator-like effectors, type II secretion systems, diversity resulting in host specificity, evolution of emerging strains, activation of susceptibility genes and strategies of host evasion. We summarize the genomic diversity in several Xanthomonas spp. and implications for disease outbreaks, management strategies and breeding for disease resistance.
Topics: Host-Pathogen Interactions; Plant Diseases; Plants; Virulence; Virulence Factors; Xanthomonas
PubMed: 32346148
DOI: 10.1038/s41579-020-0361-8 -
Cellular Microbiology Nov 2019Shigella spp. are Gram-negative enteric pathogens and the leading cause of bacterial dysentery worldwide. Since the discovery more than three decades ago that the large... (Review)
Review
Shigella spp. are Gram-negative enteric pathogens and the leading cause of bacterial dysentery worldwide. Since the discovery more than three decades ago that the large virulence plasmid of Shigella is essential for pathogenesis, our understanding of how the bacterium orchestrates inflammation and tissue destruction at the mucosal surface has been informed by studies employing the rabbit ileal loop model. Here, we outline how Phillippe Sansonetti, together with his co-workers and collaborators, exploited this model to provide a holistic view of how Shigella survives in the intestinal tract, traverses the intestinal epithelial barrier, and manipulates the host immune system to cause disease.
Topics: Animals; Dysentery, Bacillary; Host-Pathogen Interactions; Humans; Inflammation; Intestinal Mucosa; Shigella; Virulence
PubMed: 31134722
DOI: 10.1111/cmi.13062 -
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 -
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 -
Journal of Mathematical Biology Jul 2022This study explores the coevolutionary dynamics of host-pathogen interaction based on a susceptible-infected population model with density-dependent mortality. We assume...
This study explores the coevolutionary dynamics of host-pathogen interaction based on a susceptible-infected population model with density-dependent mortality. We assume that both the host's resistance and the pathogen's virulence will adaptively evolve, but there are inevitable costs in terms of host birth rate and disease-related mortality rate. Particularly, it is assumed that both the host resistance and pathogen virulence can affect the transmission rate. By using the approach of adaptive dynamics and numerical simulation, we find that the finally coevolutionary outcome depends on the strength of host-pathogen asymmetric interaction, the curvature of trade-off functions, and the intensity of density-dependent natural mortality. To be specific, firstly, we find that if the strengths of host-pathogen asymmetric interaction and disease-related mortality are relatively weak, or the density-dependent natural mortality is relatively strong, then the host resistance and pathogen virulence will evolve to a continuously stable strategy. However, if the strength of host-pathogen asymmetric interaction and disease-related mortality becomes stronger, then the host resistance and pathogen virulence will evolve periodically. Secondly, we find that if the intensities of both the birth rate trade-off function and the density-dependent natural mortality are relatively weak, but the strength of host-pathogen asymmetric interaction becomes relatively strong, then the evolution of host resistance will have a relatively strongly accelerating benefit, the evolutionary branching of host resistance will first arise. However, if the strength of host-pathogen asymmetric interaction is relatively weak, but the intensity of the trade-off function of disease-related mortality becomes relatively strong, then the evolution of pathogen virulence will have a relatively strongly decelerating cost, and the evolutionary branching of pathogen virulence will first arise. Thirdly, after the evolutionary branching of host resistance and pathogen virulence, we further study the coevolutionary dynamics of two-hosts-one-pathogen interaction and one-host-two-pathogens interaction. We find that if the evolutionary branching of host resistance arises firstly, then the finally evolutionary outcome contains a dimorphic host and a monomorphic pathogen population. If the evolutionary branching of pathogen virulence arises firstly, then the finally evolutionary outcome may contain a monomorphic host and a dimorphic pathogen population.
Topics: Biological Evolution; Computer Simulation; Host-Pathogen Interactions; Models, Biological; Virulence
PubMed: 35877051
DOI: 10.1007/s00285-022-01782-8 -
Virulence 2014Until quite recently and since the late 19(th) century, medical microbiology has been based on the assumption that some micro-organisms are pathogens and others are not.... (Review)
Review
Until quite recently and since the late 19(th) century, medical microbiology has been based on the assumption that some micro-organisms are pathogens and others are not. This binary view is now strongly criticized and is even becoming untenable. We first provide a historical overview of the changing nature of host-parasite interactions, in which we argue that large-scale sequencing not only shows that identifying the roots of pathogenesis is much more complicated than previously thought, but also forces us to reconsider what a pathogen is. To address the challenge of defining a pathogen in post-genomic science, we present and discuss recent results that embrace the microbial genetic diversity (both within- and between-host) and underline the relevance of microbial ecology and evolution. By analyzing and extending earlier work on the concept of pathogen, we propose pathogenicity (or virulence) should be viewed as a dynamical feature of an interaction between a host and microbes.
Topics: Animals; Bacteria; Biological Evolution; Fungi; Genetic Variation; Host-Parasite Interactions; Host-Pathogen Interactions; Humans; Virulence; Viruses
PubMed: 25483864
DOI: 10.4161/21505594.2014.960726 -
Annual Review of Microbiology 2013Fusarium is a genus of filamentous fungi that contains many agronomically important plant pathogens, mycotoxin producers, and opportunistic human pathogens. Comparative... (Review)
Review
Fusarium is a genus of filamentous fungi that contains many agronomically important plant pathogens, mycotoxin producers, and opportunistic human pathogens. Comparative analyses have revealed that the Fusarium genome is compartmentalized into regions responsible for primary metabolism and reproduction (core genome), and pathogen virulence, host specialization, and possibly other functions (adaptive genome). Genes involved in virulence and host specialization are located on pathogenicity chromosomes within strains pathogenic to tomato (Fusarium oxysporum f. sp. lycopersici) and pea (Fusarium 'solani' f. sp. pisi). The experimental transfer of pathogenicity chromosomes from F. oxysporum f. sp. lycopersici into a nonpathogen transformed the latter into a tomato pathogen. Thus, horizontal transfer may explain the polyphyletic origins of host specificity within the genus. Additional genome-scale comparative and functional studies are needed to elucidate the evolution and diversity of pathogenicity mechanisms, which may help inform novel disease management strategies against fusarial pathogens.
Topics: Fungal Proteins; Fusarium; Genome, Fungal; Phylogeny; Plant Diseases; Virulence
PubMed: 24024636
DOI: 10.1146/annurev-micro-092412-155650 -
PLoS Pathogens Dec 2018
Review
Topics: Animals; Bacteria; Bacterial Infections; Host-Pathogen Interactions; Humans; Virulence
PubMed: 30543716
DOI: 10.1371/journal.ppat.1007380 -
Annual Review of Phytopathology 2002We hypothesize that the evolutionary potential of a pathogen population is reflected in its population genetic structure. Pathogen populations with a high evolutionary... (Review)
Review
We hypothesize that the evolutionary potential of a pathogen population is reflected in its population genetic structure. Pathogen populations with a high evolutionary potential are more likely to overcome genetic resistance than pathogen populations with a low evolutionary potential. We propose a flexible framework to predict the evolutionary potential of pathogen populations based on analysis of their genetic structure. According to this framework, pathogens that pose the greatest risk of breaking down resistance genes have a mixed reproduction system, a high potential for genotype flow, large effective population sizes, and high mutation rates. The lowest risk pathogens are those with strict asexual reproduction, low potential for gene flow, small effective population sizes, and low mutation rates. We present examples of high-risk and low-risk pathogens. We propose general guidelines for a rational approach to breed durable resistance according to the evolutionary potential of the pathogen.
Topics: Bacteria; Evolution, Molecular; Fungi; Immunity, Innate; Mutation; Plant Diseases; Plants; Plants, Genetically Modified; Reproduction; Virulence
PubMed: 12147764
DOI: 10.1146/annurev.phyto.40.120501.101443