scholarly journals Fusarium oxysporum gas1 Encodes a Putative β-1, 3-Glucanosyltransferase Required for Virulence on Tomato Plants

2005 ◽  
Vol 18 (11) ◽  
pp. 1140-1147 ◽  
Author(s):  
Zaira Caracuel ◽  
Ana Lilia Martínez-Rocha ◽  
Antonio Di Pietro ◽  
Marta P. Madrid ◽  
M. Isabel G. Roncero
Keyword(s):  
Cell Wall ◽  
Fusarium Oxysporum ◽  
Mutational Analysis ◽  
Gene Knockout ◽  
Colony Growth ◽  
Cell Wall Degrading Enzymes ◽  
Gene Encoding ◽  
Fungal Cell ◽  
Ph Response

Glycosylphosphatidylinositol-anchored (β)-1,3-glucanosyltransferases play active roles in fungal cell wall biosynthesis and morphogenesis and have been implicated in virulence on mammals. The role of β-1,3-glucanosyltransferases in pathogenesis to plants has not been explored so far. Here, we report the cloning and mutational analysis of the gas1 gene encoding a putative β-1,3-glucanosyltransferase from the vascular wilt fungus Fusarium oxysporum. In contrast to Candida albicans, expression of gas1 in F. oxysporum was independent of ambient pH and of the pH response transcription factor PacC. Gene knockout mutants lacking a functional gas1 allele grew in a way similar to the wild-type strain in submerged culture but exhibited restricted colony growth on solid substrates. The restricted growth phenotype was relieved by the osmotic stabilizer sorbitol, indicating that it may be related to structural alterations in the cell wall. Consistent with this hypothesis, Δgas1 mutants exhibited enhanced resistance to cell wall-degrading enzymes and increased transcript levels of chsV and rho1, encoding a class V chitin synthase and a small monomeric G protein, respectively. The Δgas1 mutants showed dramatically reduced virulence on tomato, both in a root infection assay and in a fruit tissue-invasion model, thus providing the first evidence for an essential role of fungal β-1,3-glucanosyltransferases during plant infection.

scholarly journals The Transcription Factor Con7-1 Is a Master Regulator of Morphogenesis and Virulence in Fusarium oxysporum

2015 ◽  
Vol 28 (1) ◽  
pp. 55-68 ◽  
Author(s):  
Carmen Ruiz-Roldán ◽  
Yolanda Pareja-Jaime ◽  
José Antonio González-Reyes ◽  
M. Isabel G. Roncero
Keyword(s):  
Cell Wall ◽  
Fusarium Oxysporum ◽  
Gene Expression Analysis ◽  
Wall Structure ◽  
Targeted Deletion ◽  
Signal Perception ◽  
Cell Wall Biogenesis ◽  
Primary And Secondary Metabolism ◽  
Genes Encoding

Previous studies have demonstrated the essential role of morphogenetic regulation in Fusarium oxysporum pathogenesis, including processes such as cell-wall biogenesis, cell division, and differentiation of infection-like structures. We identified three F. oxysporum genes encoding predicted transcription factors showing significant identities to Magnaporthe oryzae Con7p, Con7-1, plus two identical copies of Con7-2. Targeted deletion of con7-1 produced nonpathogenic mutants with altered morphogenesis, including defects in cell wall structure, polar growth, hyphal branching, and conidiation. By contrast, simultaneous inactivation of both con7-2 copies caused no detectable defects in the resulting mutants. Comparative microarray-based gene expression analysis indicated that Con7-1 modulates the expression of a large number of genes involved in different biological functions, including host–pathogen interactions, morphogenesis and development, signal perception and transduction, transcriptional regulation, and primary and secondary metabolism. Taken together, our results point to Con7-1 as general regulator of morphogenesis and virulence in F. oxysporum.

scholarly journals Whole Genome Sequencing of Fusarium fujikuroi Provides Insight into the Role of Secretory Proteins and Cell Wall Degrading Enzymes in Causing Bakanae Disease of Rice

2017 ◽  
Vol 8 ◽  
Author(s):  
Bishnu M. Bashyal ◽  
Kirti Rawat ◽  
Sapna Sharma ◽  
Deepika Kulshreshtha ◽  
S. Gopala Krishnan ◽  
...  
Keyword(s):  
Cell Wall ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Fusarium Fujikuroi ◽  
Secretory Proteins ◽  
Whole Genome ◽  
Cell Wall Degrading Enzymes ◽  
Bakanae Disease ◽  
Insight Into

scholarly journals Protein Glycosylation inAspergillus fumigatusIs Essential for Cell Wall Synthesis and Serves as a Promising Model of Multicellular Eukaryotic Development

2012 ◽  
Vol 2012 ◽  
pp. 1-21 ◽  
Author(s):  
Cheng Jin
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Wall ◽  
Posttranslational Modification ◽  
Mammalian Cells ◽  
Protein Glycosylation ◽  
Cell Wall Synthesis ◽  
Fungal Cell ◽  
Multiple Functions ◽  
Significant Attention

Glycosylation is a conserved posttranslational modification that is found in all eukaryotes, which helps generate proteins with multiple functions. Our knowledge of glycosylation mainly comes from the investigation of the yeastSaccharomyces cerevisiaeand mammalian cells. However, during the last decade, glycosylation in the human pathogenic moldAspergillus fumigatushas drawn significant attention. It has been revealed that glycosylation inA. fumigatusis crucial for its growth, cell wall synthesis, and development and that the process is more complicated than that found in the budding yeastS. cerevisiae. The present paper implies that the investigation of glycosylation inA. fumigatusis not only vital for elucidating the mechanism of fungal cell wall synthesis, which will benefit the design of new antifungal therapies, but also helps to understand the role of protein glycosylation in the development of multicellular eukaryotes. This paper describes the advances in functional analysis of protein glycosylation inA. fumigatus.

scholarly journals Induction of Fusarium lytic Enzymes by Extracts from Resistant and Susceptible Cultivars of Pea (Pisum sativum L.)

Pathogens ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 976
Author(s):  
Lakshmipriya Perincherry ◽  
Chaima Ajmi ◽  
Souheib Oueslati ◽  
Agnieszka Waśkiewicz ◽  
Łukasz Stępień
Keyword(s):  
Cell Wall ◽  
Plant Extracts ◽  
Plant Cell Wall ◽  
Pathogenic Fungi ◽  
Human Beings ◽  
Cell Wall Degrading Enzymes ◽  
Lytic Enzymes ◽  
Mycelium Growth ◽  
Oat Bran

Being pathogenic fungi, Fusarium produce various extracellular cell wall-degrading enzymes (CWDEs) that degrade the polysaccharides in the plant cell wall. They also produce mycotoxins that contaminate grains, thereby posing a serious threat to animals and human beings. Exposure to mycotoxins occurs through ingestion of contaminated grains, inhalation and through skin absorption, thereby causing mycotoxicoses. The toxins weaken the host plant, allowing the pathogen to invade successfully, with the efficiency varying from strain to strain and depending on the plant infected. Fusariumoxysporum predominantly produces moniliformin and cyclodepsipeptides, whereas F. proliferatum produces fumonisins. The aim of the study was to understand the role of various substrates and pea plant extracts in inducing the production of CWDEs and mycotoxins. Additionally, to monitor the differences in their levels when susceptible and resistant pea plant extracts were supplemented. The cultures of F. proliferatum and F. oxysporum strains were supplemented with various potential inducers of CWDEs. During the initial days after the addition of substrates, the fungus cocultivated with pea extracts and other carbon substrates showed increased activities of β-glucosidase, xylanase, exo-1,4-glucanase and lipase. The highest inhibition of mycelium growth (57%) was found in the cultures of F. proliferatum strain PEA1 upon the addition of cv. Sokolik extract. The lowest fumonisin content was exhibited by the cultures with the pea extracts and oat bran added, and this can be related to the secondary metabolites and antioxidants present in these substrates.

scholarly journals Editorial: The Role of the Fungal Cell Wall in Host-Fungal Interactions

2020 ◽  
Vol 10 ◽  
Author(s):  
Laura Alcazar-Fuoli ◽  
Jagadeesh Bayry ◽  
Vishukumar Aimanianda
Keyword(s):  
Cell Wall ◽  
Fungal Cell Wall ◽  
Fungal Cell ◽  
Fungal Interactions

scholarly journals The regulatory and transcriptional landscape associated with carbon utilization in a filamentous fungus

2020 ◽  
Vol 117 (11) ◽  
pp. 6003-6013 ◽  
Author(s):  
Vincent W. Wu ◽  
Nils Thieme ◽  
Lori B. Huberman ◽  
Axel Dietschmann ◽  
David J. Kowbel ◽  
...  
Keyword(s):  
Cell Wall ◽  
Transcription Factors ◽  
Plant Cell ◽  
Plant Cell Wall ◽  
Plant Biomass ◽  
Carbon Sources ◽  
Cell Wall Degrading Enzymes ◽  
Degrading Enzymes ◽  
Genes Encoding

Filamentous fungi, such asNeurospora crassa, are very efficient in deconstructing plant biomass by the secretion of an arsenal of plant cell wall-degrading enzymes, by remodeling metabolism to accommodate production of secreted enzymes, and by enabling transport and intracellular utilization of plant biomass components. Although a number of enzymes and transcriptional regulators involved in plant biomass utilization have been identified, how filamentous fungi sense and integrate nutritional information encoded in the plant cell wall into a regulatory hierarchy for optimal utilization of complex carbon sources is not understood. Here, we performed transcriptional profiling ofN. crassaon 40 different carbon sources, including plant biomass, to provide data on how fungi sense simple to complex carbohydrates. From these data, we identified regulatory factors inN. crassaand characterized one (PDR-2) associated with pectin utilization and one with pectin/hemicellulose utilization (ARA-1). Using in vitro DNA affinity purification sequencing (DAP-seq), we identified direct targets of transcription factors involved in regulating genes encoding plant cell wall-degrading enzymes. In particular, our data clarified the role of the transcription factor VIB-1 in the regulation of genes encoding plant cell wall-degrading enzymes and nutrient scavenging and revealed a major role of the carbon catabolite repressor CRE-1 in regulating the expression of major facilitator transporter genes. These data contribute to a more complete understanding of cross talk between transcription factors and their target genes, which are involved in regulating nutrient sensing and plant biomass utilization on a global level.

scholarly journals The Chitin Connection

mBio ◽  
2012 ◽  
Vol 3 (2) ◽  
Author(s):  
David L. Goldman ◽  
Alfin G. Vicencio
Keyword(s):  
Cell Wall ◽  
Cell Membrane ◽  
Fungal Infections ◽  
Allergic Inflammation ◽  
Chitinase Activity ◽  
Chitin Deacetylase ◽  
Fungal Cell ◽  
Content Type ◽  
Covalently Linked

ABSTRACTChitin, a polymer ofN-acetylglucosamine, is an essential component of the fungal cell wall. Chitosan, a deacetylated form of chitin, is also important in maintaining cell wall integrity and is essential forCryptococcus neoformansvirulence. In their article, Gilbert et al. [N. M. Gilbert, L. G. Baker, C. A. Specht, and J. K. Lodge, mBio 3(1):e00007-12, 2012] demonstrate that the enzyme responsible for chitosan synthesis, chitin deacetylase (CDA), is differentially attached to the cell membrane and wall. Bioactivity is localized to the cell membrane, where it is covalently linked via a glycosylphosphatidylinositol (GPI) anchor. Findings from this study significantly enhance our understanding of cryptococcal cell wall biology. Besides the role of chitin in supporting structural stability, chitin and host enzymes with chitinase activity have an important role in host defense and modifying the inflammatory response. Thus, chitin appears to provide a link between the fungus and host that involves both innate and adaptive immune responses. Recently, there has been increased attention to the role of chitinases in the pathogenesis of allergic inflammation, especially asthma. We review these findings and explore the possible connection between fungal infections, the induction of chitinases, and asthma.

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