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BMC Microbiology Aug 2023Vascular system is affected by diseases that can seriously damage plant health by inducing browning and death of branches. This study aimed to identify and analyze the...
BACKGROUND
Vascular system is affected by diseases that can seriously damage plant health by inducing browning and death of branches. This study aimed to identify and analyze the pathogenicity of Fusarium spp. isolates obtained from diseased peach branches in several peach-producing areas of China.
RESULTS
We obtained and confirmed nine Fusarium isolates based on morphological and molecular characteristics. Phylogenetic relationships using a combination of rDNA-internal transcribed spacer (ITS), elongation factor (EF)-1α, and mitochondrial small subunit (mtSSU) gene sequences were analyzed. GJH-Z1, GJH-6, and GJH-1 were identified as F. avenaceum; HYR-Z3, and ZLZT-6 as F. concentricum, HH-2020-G2, and HYTZ-4 as F. solani, GG-2020-1 as F. asiaticum, SYGZ-1 as F. equiseti. Through acupuncture comparison, the pathogenicity of F. equiseti (SYGZ-1) was highest amongst nine strains. Meanwhile, F. concentricum (HYR-Z3 and ZLZT-6), and F. solaini (HYTZ-4) had a higher level of pathogenicity as revealed by impregnation.
CONCLUSIONS
Our study shed light on the findings that Fusarium spp. can inflict vascular bundle browning of peach plants. Our results will extend the understanding of pathogenic diseases in China's peach industry.
Topics: Fusarium; Prunus persica; Phylogeny; Virulence; China
PubMed: 37550608
DOI: 10.1186/s12866-023-02958-y -
Molecular Oral Microbiology Feb 2021Polyamines are positively charged hydrocarbons that are essential for the growth and cellular maintenance in prokaryotes and eukaryotes. Polyamines have been... (Review)
Review
Polyamines are positively charged hydrocarbons that are essential for the growth and cellular maintenance in prokaryotes and eukaryotes. Polyamines have been demonstrated to play a role in bacterial pathogenicity and biofilm formation. However, the role of extracellular polyamines as a signaling molecule in the regulation of virulence is not investigated in detail. The bacterial pathogens residing in the respiratory tract remain asymptomatic for an extended period; however, the factors that lead to symptomatic behavior are poorly understood. Further investigation to understand the relation between the host-secreted factors and virulence of pathogenic bacteria in the respiratory tract may provide insights into the pathogenesis of respiratory tract infections. Polyamines produced within the bacterial cell are generally sequestered. Therefore, the pool of extracellular polyamines formed by secretion of the commensals and the host may be one of the signaling molecules that might contribute toward the alterations in the expression of virulence factors in bacterial pathogens. Besides, convergent mechanisms of polyamine biosynthesis do exist across the border of species and genus level. Also, several novel polyamine transporters in the host and bacteria remain yet to be identified. The review focuses on the role of polyamines in the expression of virulence phenotypes and biofilm formation of the respiratory tract pathogens.
Topics: Bacteria; Polyamines; Respiratory System; Virulence; Virulence Factors
PubMed: 32979241
DOI: 10.1111/omi.12315 -
Current Drug Metabolism 2018Pathogenic microbes routinely keep encountering different types of stress in their environment such as high osmolarity, high temperature, pH fluctuations in host gut... (Review)
Review
BACKGROUND
Pathogenic microbes routinely keep encountering different types of stress in their environment such as high osmolarity, high temperature, pH fluctuations in host gut etc. They tend to acquire certain small molecular weight molecules, termed osmolytes, so as to handle these challenges and survive in harsh conditions. These osmolytes include some which are self-synthesized by the microorganisms, while majority of them are imbibed from the external environment via osmolyte transporters.
METHODS
In this review, we have discussed work done on osmolytes and their transport systems, which influence upon sustenance and virulence of the pathogens under the given stress conditions.
RESULTS
Osmolytes and their transport systems play vital role in efficient maintenance of cell turgidity and electrolyte levels for proper cell functioning. These molecules don't disturb normal metabolic processes within the microbial cell at all; it rather stabilizes the macromolecules, such as nucleic acids and proteins. Besides, these osmolytes also empower the microbes with the pathogenicity potential under harsh conditions such as salt, pH, temperature stress, and the efficient host immunity.
CONCLUSION
Exploring avenues with respect to osmolyte transport systems is the need of the hour especially in this time where we are facing the evolution of antibiotic resistance in pathogens. Most interestingly, a detailed study of bacterial stress responses would prove to be useful in comprehending what these pathogens face in the host microenvironment, whereby we can manipulate the pathogen survival in human gut, and hence address the menace of pathogenic resistance in humans as well as animals.
Topics: Animals; Bacteria; Carrier Proteins; Humans; Osmolar Concentration; Plasmodium; Protein Stability; Urinary Tract Infections; Virulence
PubMed: 29938617
DOI: 10.2174/1389200219666180625113446 -
Trends in Ecology & Evolution Dec 2017Bacteria that cause serious disease often have smaller genomes, and fewer genes, than their nonpathogenic, or less pathogenic relatives. Here, we review evidence for the... (Review)
Review
Bacteria that cause serious disease often have smaller genomes, and fewer genes, than their nonpathogenic, or less pathogenic relatives. Here, we review evidence for the generality of this association, and summarise the various reasons why the association might hold. We focus on the population genetic processes that might lead to reductive genome evolution, and show how several of these could be connected to pathogenicity. We find some evidence for most of the processes having acted in bacterial pathogens, including several different modes of genome reduction acting in the same lineage. We argue that predictable processes of genome evolution might not reflect any common underlying process.
Topics: Bacteria; Evolution, Molecular; Genome, Bacterial; Virulence
PubMed: 29054300
DOI: 10.1016/j.tree.2017.09.006 -
Virulence Dec 2019Opportunistic commensal and environmental fungi can cause superficial to systemic diseases in humans. But how did these pathogens adapt to infect us and how does... (Review)
Review
Opportunistic commensal and environmental fungi can cause superficial to systemic diseases in humans. But how did these pathogens adapt to infect us and how does host-pathogen co-evolution shape their virulence potential? During evolution toward pathogenicity, not only do microorganisms gain virulence genes, but they also tend to lose non-adaptive genes in the host niche. Additionally, virulence factors can become detrimental during infection when they trigger host recognition. The loss of non-adaptive genes as well as the loss of the virulence potential of genes by adaptations to the host has been investigated in pathogenic bacteria and phytopathogenic fungi, where they are known as antivirulence and avirulence genes, respectively. However, these concepts are nearly unknown in the field of pathogenic fungi of humans. We think that this unnecessarily limits our view of human-fungal interplay, and that much could be learned if we applied a similar framework to aspects of these interactions. In this review, we, therefore, define and adapt the concepts of antivirulence and avirulence genes for human pathogenic fungi. We provide examples for analogies to antivirulence genes of bacterial pathogens and to avirulence genes of phytopathogenic fungi. Introducing these terms to the field of pathogenic fungi of humans can help to better comprehend the emergence and evolution of fungal virulence and disease.
Topics: Adaptation, Physiological; Animals; Evolution, Molecular; Fungi; Genes, Fungal; Host-Pathogen Interactions; Humans; Mice; Virulence; Virulence Factors
PubMed: 31711357
DOI: 10.1080/21505594.2019.1688753 -
Cold Spring Harbor Perspectives in... Aug 2014We review here recent advances in our understanding of sexual reproduction in fungal pathogens that commonly infect humans, including Candida albicans, Cryptococcus... (Review)
Review
We review here recent advances in our understanding of sexual reproduction in fungal pathogens that commonly infect humans, including Candida albicans, Cryptococcus neoformans/gattii, and Aspergillus fumigatus. Where appropriate or relevant, we introduce findings on other species associated with human infections. In particular, we focus on rapid advances involving genetic, genomic, and population genetic approaches that have reshaped our view of how fungal pathogens evolve. Rather than being asexual, mitotic, and largely clonal, as was thought to be prevalent as recently as a decade ago, we now appreciate that the vast majority of pathogenic fungi have retained extant sexual, or parasexual, cycles. In some examples, sexual and parasexual unions of pathogenic fungi involve closely related individuals, generating diversity in the population but with more restricted recombination than expected from fertile, sexual, outcrossing and recombining populations. In other cases, species and isolates participate in global outcrossing populations with the capacity for considerable levels of gene flow. These findings illustrate general principles of eukaryotic pathogen emergence with relevance for other fungi, parasitic eukaryotic pathogens, and both unicellular and multicellular eukaryotic organisms.
Topics: Drug Resistance, Fungal; Fungi; Humans; Hyphae; Mycoses; Reproduction; Self-Fertilization; Virulence
PubMed: 25085958
DOI: 10.1101/cshperspect.a019281 -
Annual Review of Food Science and... Mar 2019Bacteriophages (phages) have traditionally been considered troublesome in food fermentations, as they are an important cause of starter-culture failure and trigger... (Review)
Review
Bacteriophages (phages) have traditionally been considered troublesome in food fermentations, as they are an important cause of starter-culture failure and trigger significant financial losses. In addition, from an evolutionary perspective, phages have contributed to the pathogenicity of many bacteria through transduction of virulence genes. In contrast, phages have played an important positive role in molecular biology. Moreover, these agents are increasingly being recognized as a potential solution to the detection and biocontrol of various undesirable bacteria, which cause either spoilage of food materials, decreased microbiological safety of foods, or infectious diseases in food animals and crops. The documented successful applications of phages and various phage-derived molecules are discussed in this review, as are many promising new uses that are currently under development.
Topics: Animals; Bacteria; Bacteriophages; Crops, Agricultural; Food Microbiology; Genes, Viral; Virulence
PubMed: 30633564
DOI: 10.1146/annurev-food-032818-121747 -
Microbiology Spectrum Jun 2016Bacterial pathogens must endure or adapt to different environments and stresses during transmission and infection. Posttranscriptional gene expression control by... (Review)
Review
Bacterial pathogens must endure or adapt to different environments and stresses during transmission and infection. Posttranscriptional gene expression control by regulatory RNAs, such as small RNAs and riboswitches, is now considered central to adaptation in many bacteria, including pathogens. The study of RNA-based regulation (riboregulation) in pathogenic species has provided novel insight into how these bacteria regulate virulence gene expression. It has also uncovered diverse mechanisms by which bacterial small RNAs, in general, globally control gene expression. Riboregulators as well as their targets may also prove to be alternative targets or provide new strategies for antimicrobials. In this article, we present an overview of the general mechanisms that bacteria use to regulate with RNA, focusing on examples from pathogens. In addition, we also briefly review how deep sequencing approaches have aided in opening new perspectives in small RNA identification and the study of their functions. Finally, we discuss examples of riboregulators in two model pathogens that control virulence factor expression or survival-associated phenotypes, such as stress tolerance, biofilm formation, or cell-cell communication, to illustrate how riboregulation factors into regulatory networks in bacterial pathogens.
Topics: Adaptation, Physiological; Bacteria; Bacterial Physiological Phenomena; Gene Expression Regulation, Bacterial; RNA, Small Untranslated; Virulence; Virulence Factors
PubMed: 27337442
DOI: 10.1128/microbiolspec.VMBF-0028-2015 -
Sheng Wu Gong Cheng Xue Bao = Chinese... Sep 2017Biofilms are complex three-dimensional bacterial assemblages that attach to biotic or abiotic solid surfaces, and frequently embed within a self-produced matrix of... (Review)
Review
Biofilms are complex three-dimensional bacterial assemblages that attach to biotic or abiotic solid surfaces, and frequently embed within a self-produced matrix of extracellular polymeric substances. Biofilm formation is a microbial defense response to biotic and abiotic stresses, and a key factor for survival in adverse environments. A wide variety of microorganisms can colonize distant tissues of higher plants, such as leaves, vascular network and roots, and adhere to the surface of the tissues to form biofilms. The dynamic processes in forming biofilms in response to plant internal environment are key steps required for full virulence of phytopathogenic bacteria. Exploring the mechanisms involved in regulation of bacterial biofilms is important for understanding the plant-pathogens interactions. In this review, we summarized the research progresses related to the biofilms of bacterial phytopathogens, including biofilm characteristics, essential regulatory mechanisms and key signals affecting the transition between a planktonic lifestyle and multicellular behavior.
Topics: Bacteria; Biofilms; Host-Pathogen Interactions; Plant Diseases; Plants; Virulence
PubMed: 28956407
DOI: 10.13345/j.cjb.170079 -
International Journal of Molecular... Aug 2023is a devastating fungal pathogen that causes severe crop losses worldwide. It is of vital importance to understand its pathogenic mechanism for disease control. Through...
is a devastating fungal pathogen that causes severe crop losses worldwide. It is of vital importance to understand its pathogenic mechanism for disease control. Through a forward genetic screen combined with next-generation sequencing, a putative protein kinase, Cak1, was found to be involved in the growth and pathogenicity of . Knockout and complementation experiments confirmed that deletions in caused defects in mycelium and sclerotia development, as well as appressoria formation and host penetration, leading to complete loss of virulence. These findings suggest that Cak1 is essential for the growth, development, and pathogenicity of . Therefore, Cak1 could serve as a potential target for the control of infection through host-induced gene silencing (HIGS), which could increase crop resistance to the pathogen.
Topics: Virulence; Ascomycota; Gene Silencing; High-Throughput Nucleotide Sequencing
PubMed: 37628791
DOI: 10.3390/ijms241612610