-
Frontiers in Cellular and Infection... 2022Mycoplasmas as economically important and pantropic pathogens can cause similar clinical diseases in different hosts by eluding host defense and establishing their... (Review)
Review
Mycoplasmas as economically important and pantropic pathogens can cause similar clinical diseases in different hosts by eluding host defense and establishing their niches despite their limited metabolic capacities. Besides, enormous undiscovered virulence has a fundamental role in the pathogenesis of pathogenic mycoplasmas. On the other hand, they are host-specific pathogens with some highly pathogenic members that can colonize a vast number of habitats. Reshuffling mycoplasmas genetic information and evolving rapidly is a way to avoid their host's immune system. However, currently, only a few control measures exist against some mycoplasmosis which are far from satisfaction. This review aimed to provide an updated insight into the state of mycoplasmas as pathogens by summarizing and analyzing the comprehensive progress, current challenge, and future perspectives of mycoplasmas. It covers clinical implications of mycoplasmas in humans and domestic and wild animals, virulence-related factors, the process of gene transfer and its crucial prospects, the current application and future perspectives of nanotechnology for diagnosing and curing mycoplasmosis, vaccination, and protective immunity. Several questions remain unanswered and are recommended to pay close attention to. The findings would be helpful to develop new strategies for basic and applied research on mycoplasmas and facilitate the control of mycoplasmosis for humans and various species of animals.
Topics: Animals; Mycoplasma; Mycoplasma Infections; Virulence; Virulence Factors
PubMed: 35646746
DOI: 10.3389/fcimb.2022.855731 -
International Journal of Molecular... Apr 2019Cystic fibrosis (CF) is an autosomal recessive genetic disorder which leads to the secretion of a viscous mucus layer on the respiratory epithelium that facilitates... (Review)
Review
Cystic fibrosis (CF) is an autosomal recessive genetic disorder which leads to the secretion of a viscous mucus layer on the respiratory epithelium that facilitates colonization by various bacterial pathogens. The problem of drug resistance has been reported for all the species able to colonize the lung of CF patients, so alternative treatments are urgently needed. In this context, a valid approach is to investigate new natural and synthetic molecules for their ability to counteract alternative pathways, such as virulence regulating quorum sensing (QS). In this review we describe the pathogens most commonly associated with CF lung infections: , , species of the complex and the emerging pathogens , and non-tuberculous Mycobacteria. For each bacterium, the QS system(s) and the molecules targeting the different components of this pathway are described. The amount of investigations published in the last five years clearly indicate the interest and the expectations on antivirulence therapy as an alternative to classical antibiotics.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Bacterial Infections; Cystic Fibrosis; Drug Discovery; Humans; Quorum Sensing; Virulence; Virulence Factors
PubMed: 31013936
DOI: 10.3390/ijms20081838 -
Journal of Microbiology (Seoul, Korea) Mar 2016Oxylipins are a class of molecules derived from the incorporation of oxygen into polyunsaturated fatty acid substrates through the action of oxygenases. While... (Review)
Review
Oxylipins are a class of molecules derived from the incorporation of oxygen into polyunsaturated fatty acid substrates through the action of oxygenases. While extensively investigated in the context of mammalian immune responses, over the last decade it has become apparent that oxylipins are a common means of communication among and between plants, animals, and fungi to control development and alter host-microbe interactions. In fungi, some oxylipins are derived nonenzymatically while others are produced by lipoxygenases, cyclooxygenases, and monooxygenases with homology to plant and human enzymes. Recent investigations of numerous plant and human fungal pathogens have revealed oxylipins to be involved in the establishment and progression of disease. This review highlights oxylipin production by pathogenic fungi and their role in fungal development and pathogen/host interactions.
Topics: Animals; Fungi; Host-Pathogen Interactions; Humans; Immunity, Active; Mycoses; Oxygenases; Oxylipins; Plant Diseases; Plants; Virulence
PubMed: 26920885
DOI: 10.1007/s12275-016-5620-z -
PLoS Pathogens Feb 2015DNA can form several secondary structures besides the classic double helix: one that has received much attention in recent years is the G-quadruplex (G4). This is a... (Review)
Review
DNA can form several secondary structures besides the classic double helix: one that has received much attention in recent years is the G-quadruplex (G4). This is a stable four-stranded structure formed by the stacking of quartets of guanine bases. Recent work has convincingly shown that G4s can form in vivo as well as in vitro and can affect both replication and transcription of DNA. They also play important roles at G-rich telomeres. Now, a spate of exciting reports has begun to reveal roles for G4 structures in virulence processes in several important microbial pathogens of humans. Interestingly, these come from a range of kingdoms--bacteria and protozoa as well as viruses--and all facilitate immune evasion in different ways. In particular, roles for G4s have been posited in the antigenic variation systems of bacteria and protozoa, as well as in the silencing of at least two major human viruses, human immunodeficiency virus (HIV) and Epstein-Barr virus (EBV). Although antigenic variation and the silencing of latent viruses are quite distinct from one another, both are routes to immune evasion and the maintenance of chronic infections. Thus, highly disparate pathogens can use G4 motifs to control DNA/RNA dynamics in ways that are relevant to common virulence phenotypes. This review explores the evidence for G4 biology in such processes across a range of important human pathogens.
Topics: Bacteria; G-Quadruplexes; Humans; Virulence; Viruses
PubMed: 25654363
DOI: 10.1371/journal.ppat.1004562 -
Genome Biology and Evolution May 2016Fungal pathogens of plants and animals have multifarious effects; they cause devastating damages to agricultures, lead to life-threatening diseases in humans, or induce...
Fungal pathogens of plants and animals have multifarious effects; they cause devastating damages to agricultures, lead to life-threatening diseases in humans, or induce beneficial effects by reducing insect pest populations. Many virulence factors have been determined in different fungal pathogens; however, the molecular determinants contributing to fungal host selection and adaptation are largely unknown. In this study, we sequenced the genomes of seven ascomycete insect pathogens and performed the genome-wide analyses of 33 species of filamentous ascomycete pathogenic fungi that infect insects (12 species), plants (12), and humans (9). Our results revealed that the genomes of plant pathogens encode more proteins and protein families than the insect and human pathogens. Unexpectedly, more common orthologous protein groups are shared between the insect and plant pathogens than between the two animal group pathogens. We also found that the pathogenicity of host-adapted fungi evolved multiple times, and that both divergent and convergent evolutions occurred during pathogen-host cospeciation thus resulting in protein families with similar features in each fungal group. However, the role of phylogenetic relatedness on the evolution of protein families and therefore pathotype formation could not be ruled out due to the effect of common ancestry. The evolutionary correlation analyses led to the identification of different protein families that correlated with alternate pathotypes. Particularly, the effector-like proteins identified in plant and animal pathogens were strongly linked to fungal host adaptation, suggesting the existence of similar gene-for-gene relationships in fungus-animal interactions that has not been established before. These results well advance our understanding of the evolution of fungal pathogenicity and the factors that contribute to fungal pathotype formation.
Topics: Animals; Ascomycota; Evolution, Molecular; Genome, Fungal; Humans; Insecta; Plant Diseases; Plants; Virulence; Virulence Factors
PubMed: 27071652
DOI: 10.1093/gbe/evw082 -
Frontiers in Cellular and Infection... 2022is a zoonotic pathogen that can cause fatal disease in patients who are immunocompromised. At present, the epidemiology and pathogenic mechanisms of infection are not...
is a zoonotic pathogen that can cause fatal disease in patients who are immunocompromised. At present, the epidemiology and pathogenic mechanisms of infection are not clear. This study characterized the genomes of 53 strains from different sources. Pan-genome analysis showed that all strains contained 11481 pan genes, including 3690 core genes and 602 ~ 1079 accessory genes. Functional annotation of pan genome focused on the genes related to basic lifestyle, such as the storage and expression of metabolic and genetic information. Phylogenetic analysis based on pan-genome showed that the strains were clustered into six clades, which was not directly related to the isolation location and host source. Also, a total of 84 virulence genes were predicted in 53 strains. These virulence factors can be divided into 20 categories related to substance metabolism, secreted protein and immune escape. Meanwhile, six antibiotic resistance genes ( and ) were detected, and all strains carried related to rifamycin resistance. In addition, 28 plasmids were found in the 53 strains, belonging to Type-A (n = 14), Type-B (n = 8) and Type-N (n = 6), respectively. The genetic structures of the same type of plasmid were highly similar. In conclusion, strains show different genomic characteristics, virulence-related genes, potential drug resistance and virulence plasmid structures, which may be conducive to the evolution of its pathogenesis.
Topics: Humans; Phylogeny; Plasmids; Rhodococcus equi; Rifamycins; Virulence
PubMed: 35252029
DOI: 10.3389/fcimb.2022.807610 -
Nucleic Acids Research Jan 2015Pathogenicity is a complex multifactorial process confounded by the concerted activity of genetic regions associated with virulence and/or resistance determinants....
Pathogenicity is a complex multifactorial process confounded by the concerted activity of genetic regions associated with virulence and/or resistance determinants. Pathogenicity islands (PAIs) and resistance islands (REIs) are key to the evolution of pathogens and appear to play complimentary roles in the process of bacterial infection. While PAIs promote disease development, REIs give a fitness advantage to the host against multiple antimicrobial agents. The Pathogenicity Island Database (PAIDB, http://www.paidb.re.kr) has been the only database dedicated to providing comprehensive information on all reported PAIs and candidate PAIs in prokaryotic genomes. In this study, we present PAIDB v2.0, whose functionality is extended to incorporate REIs. PAIDB v2.0 contains 223 types of PAIs with 1331 accessions, and 88 types of REIs with 108 accessions. With an improved detection scheme, 2673 prokaryotic genomes were analyzed to locate candidate PAIs and REIs. With additional quantitative and qualitative advancements in database content and detection accuracy, PAIDB will continue to facilitate pathogenomic studies of both pathogenic and non-pathogenic organisms.
Topics: Databases, Nucleic Acid; Drug Resistance, Microbial; Genome, Microbial; Genomic Islands; Internet; Virulence
PubMed: 25336619
DOI: 10.1093/nar/gku985 -
Annual Review of Phytopathology Sep 2023The group of strains constituting the species complex (RSSC) is a prominent model for the study of plant-pathogenic bacteria because of its impact on agriculture, owing... (Review)
Review
The group of strains constituting the species complex (RSSC) is a prominent model for the study of plant-pathogenic bacteria because of its impact on agriculture, owing to its wide host range, worldwide distribution, and long persistence in the environment. RSSC strains have led to numerous studies aimed at deciphering the molecular bases of virulence, and many biological functions and mechanisms have been described to contribute to host infection and pathogenesis. In this review, we put into perspective recent advances in our understanding of virulence in RSSC strains, both in terms of the inventory of functions that participate in this process and their evolutionary dynamics. We also present the different strategies that have been developed to combat these pathogenic strains through biological control, antimicrobial agents, plant genetics, or microbiota engineering.
Topics: Virulence; Ralstonia solanacearum; Biological Evolution
PubMed: 37506349
DOI: 10.1146/annurev-phyto-021622-104551 -
Infection and Immunity Oct 2016Historically, the nature and extent of host damage by a microbe were considered highly dependent on virulence attributes of the microbe. However, it has become clear... (Review)
Review
Historically, the nature and extent of host damage by a microbe were considered highly dependent on virulence attributes of the microbe. However, it has become clear that disease is a complex outcome which can arise because of pathogen-mediated damage, host-mediated damage, or both, with active participation from the host microbiota. This awareness led to the formulation of the damage response framework (DRF), a revolutionary concept that defined microbial virulence as a function of host immunity. The DRF outlines six classifications of host damage outcomes based on the microbe and the strength of the immune response. In this review, we revisit this concept from the perspective of Candida albicans, a microbial pathogen uniquely adapted to its human host. This fungus commonly colonizes various anatomical sites without causing notable damage. However, depending on environmental conditions, a diverse array of diseases may occur, ranging from mucosal to invasive systemic infections resulting in microbe-mediated and/or host-mediated damage. Remarkably, C. albicans infections can fit into all six DRF classifications, depending on the anatomical site and associated host immune response. Here, we highlight some of these diverse and site-specific diseases and how they fit the DRF classifications, and we describe the animal models available to uncover pathogenic mechanisms and related host immune responses.
Topics: Animals; Candida albicans; Candidiasis; Disease Models, Animal; Host-Pathogen Interactions; Humans; Microbiota; Virulence
PubMed: 27430274
DOI: 10.1128/IAI.00469-16 -
Microbial Genomics Feb 2022is a food-borne pathogen with epidemic potential that causes cholera-like acute gastroenteritis and sometimes extraintestinal infections in humans. However, research on...
is a food-borne pathogen with epidemic potential that causes cholera-like acute gastroenteritis and sometimes extraintestinal infections in humans. However, research on its genetic diversity and pathogenicity-related genetic elements based on whole genome sequences is lacking. In this study, we collected and sequenced 130 strains of from 14 provinces of China, and also determined the susceptibility of 35 of the strains to 30 different antibiotics. Combined with 52 publicly available genomes, we inferred the population structure and investigated the characteristics of pathogenicity-related factors. The strains exhibited high levels of homologous recombination and were assigned to two major populations, VflPop1 and VflPop2, according to the different compositions of their gene pools. VflPop2 was subdivided into groups 2.1 and 2.2. Except for VflPop2.2, which consisted only of Asian strains, the strains in VflPop1 and VflPop2.1 were distributed in the Americas, Asia and Europe. Analysis of the pathogenicity potential of showed that most of the identified virulence-related genes or gene clusters showed high prevalence in , except for three mobile genetic elements: pBD146, ICEInd1 and MGIInd1, which were scattered in only a few strains. A total of 21 antimicrobial resistance genes were identified in the genomes of the 182 strains analysed in this study, and 19 (90%) of them were exclusively present in VflPop2. Notably, the tetracycline resistance-related gene (35) was present in 150 (95%) of the strains in VflPop2, and in only one (4%) strain in VflPop1, indicating it was population-specific. In total, 91% of the 35 selected strains showed resistance to cefazolin, indicating has a high resistance rate to cefazolin. Among the 15 genomes that carried the previously reported drug resistance-related plasmid pBD146, 11 (73%) showed resistance to trimethoprim-sulfamethoxazole, which we inferred was related to the presence of the gene in the plasmid. On the basis of the population genomics analysis, the genetic diversity, population structure and distribution of pathogenicity-related factors of were delineated in this study. The results will provide further clues regarding the evolution and pathogenic mechanisms of , and improve our knowledge for the prevention and control of this pathogen.
Topics: Anti-Bacterial Agents; Cefazolin; Humans; Metagenomics; Vibrio; Virulence; Virulence Factors
PubMed: 35212619
DOI: 10.1099/mgen.0.000769