Project description:The parasite species complex Anisakis simplex sensu lato (Anisakis simplex sensu stricto; (A. simplex s.s.), A. pegreffii, A. simplex C) is the main cause of severe anisakiasis (allergy) worldwide and is now an important health matter. In this study, the relationship of this Anisakis species complex and their allergenic capacities is assessed by studying the differences between the two most frequent species (A. simplex s.s., A. pegreffii) and their hybrid haplotype by studying active L3 larvae parasiting Merluccius merluccius.
Project description:The similarity of Lyme borreliosis to other diseases and the complex pathogenesis cause diagnostic and therapeutic difficulties. Changes at the cellular and molecular level after Borrelia sp. infection remain still poorly understood. Therefore, the present study focused on the gene expression in human dermal fibroblasts in differentiation of infection with Borrelia garinii, Borrelia afzelii and Borrelia burgdorferi sensu stricto spirochetes. For microarray analysis 10 samples were used: 3 control samples - K, 2 samples of NHDF cells infected with Borrelia garinii - G, 2 samples of NHDF cells infected with Borrelia afzelii - A and 3 samples of NHDF cells infected with Borrelia burgdorferi sensu stricto - SS.
Project description:Fusarium graminearum is one of the most important causes of wheat scab in different parts of the world. This fungus is able to produce widespread trichothecene mycotoxins such as nivalenol (NIV) and deoxynivalenol (DON) which are harmful for both human and animals. The Fg16 target is located in chromosome 1 of the F. graminearum genome coding for a hypothetical protein whose function is not yet known. The Fg16 gene is involved in lipid biosynthesis and leads to sexual development during colonization in wheat stalks. This gene is used to detect F. graminearum and determine the lineage of F. graminearum complex species. In the present study, polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) and DNA sequencing methods were employed in screening for genetic variation in 172 F. graminearum s.s. isolates. The PCR reaction forced the amplification of 410-bp fragments of Fg16. Two single nucleotide polymorphisms (T82C and A352T) and one amino acid exchange (C65S) with three patterns (TA/TA, CT/CT and TA/CT genotypes) were found in the Fg16 gene fragment. Two haplotypes, 1A and 1B, were identified within F. graminearum s.s. populations in northern and western regions of Iran. Two different secondary structures of protein were predicted for CT/CT and TA/CT genotypes of Fg16 gene. The average diversity levels detected were relatively high (He: 0.3238; Heu: 0.334; Ho: 0.2894; mean PIC: 0.514; mean Shannon's information index: 0.4132; mean number of alleles per locus: 1.473). On the basis of the obtained results, it was revealed that the Fg16 gene had a high degree of polymorphism that can be considered for future control programming strategies and thus the associations between the SSCP patterns with different traits of F. graminearum such as wheat colonization, perithecium formation on stalk tissues and lineage discrimination should be investigated.
Project description:Fungal complexes are often composed of morphologically nearly indistinguishable species with high genetic similarity. However, despite their close relationship, they can exhibit distinct phenotypic differences in pathogenicity and production of mycotoxins. Many plant pathogenic and toxigenic fungi have been shown to consist of such cryptic species. Identification of cryptic species in economically important pathogens has added value in epidemiologic studies and provides opportunities for better control. Analysis of mitochondrial genomes or mitogenomics opens up dimensions for improved diagnostics of fungi, especially when efficient recovery of DNA is problematic. In comparison to nuclear DNA, mitochondrial DNA (mtDNA) can be amplified with improved efficacy due to its multi-copy nature. However, to date, only a few studies have demonstrated the usefulness of mtDNA for identification of cryptic species within fungal complexes. In this study, we explored the value of mtDNA for identification of one of the most important cereal pathogens Fusarium graminearum sensu stricto (F.g.). We found that homing endonucleases (HEGs), which are widely distributed in mitogenomes of fungi, display small indel polymorphism, proven to be potentially species specific. The resulting small differences in their lengths may facilitate further differentiation of F.g. from the other cryptic species belonging to F. graminearum species complex. We also explored the value of SNP analysis of the mitogenome for typing F.g. The success in identifying F.g. strains was estimated at 96%, making this tool an attractive complement to other techniques for identification of F.g.
Project description:Recent improvements in microbiology and molecular epidemiology were largely stimulated by whole- genome sequencing (WGS), which provides an unprecedented resolution in discriminating highly related genetic backgrounds. WGS is becoming the method of choice in epidemiology of fungal diseases, but its application is still in a pioneer stage, mainly due to the limited number of available genomes. Fungal pathogens often belong to complexes composed of numerous cryptic species. Detecting cryptic diversity is fundamental to understand the dynamics and the evolutionary relationships underlying disease outbreaks. In this study, we explore the value of whole-genome SNP analyses in identification of the pandemic pathogen Fusarium graminearum sensu stricto (F.g.). This species is responsible for cereal diseases and negatively impacts grain production worldwide. The fungus belongs to the monophyletic fungal complex referred to as F. graminearum species complex including at least sixteen cryptic species, a few among them may be involved in cereal diseases in certain agricultural areas. We analyzed WGS data from a collection of 99 F.g. strains and 33 strains representing all known cryptic species belonging to the FGSC complex. As a first step, we performed a phylogenomic analysis to reveal species-specific clustering. A RAxML maximum likelihood tree grouped all analyzed strains of F.g. into a single clade, supporting the clustering-based identification approach. Although, phylogenetic reconstructions are essential in detecting cryptic species, a phylogenomic tree does not fulfill the criteria for rapid and cost-effective approach for identification of fungi, due to the time-consuming nature of the analysis. As an alternative, analysis of WGS information by mapping sequence data from individual strains against reference genomes may provide useful markers for the rapid identification of fungi. We provide a robust framework for typing F.g. through the web-based PhaME workflow available at EDGE bioinformatics. The method was validated through multiple comparisons of assembly genomes to F.g. reference strain PH-1. We showed that the difference between intra- and interspecies variability was at least two times higher than intraspecific variation facilitating successful typing of F.g. This is the first study which employs WGS data for typing plant pathogenic fusaria.
Project description:Fusarium graminearum (teleomorph Gibberella zeae) is a prominent pathogen that infects major cereal crops, such as wheat, barley, and maize. To dissect molecular mechanisms for initial stage of perithecia development, we compared transcriptomes of fungal cultures harvested from F. graminearum wild-type strain Z-3639, abaA, and fpo1 at 1 day after sexual induction.
Project description:Fusarium graminearum (teleomorph Gibberella zeae) is a prominent pathogen that infects major cereal crops, such as wheat, barley, and maize. To dissect molecular mechanisms of small non-coding RNA-mediated gene regulation during ascospore production, we compared transcriptomes of fungal cultures harvested from F. graminearum wild-type strain Z-3639 and RNAi component mutants at 5 days after sexual induction.
Project description:The similarity of Lyme borreliosis to other diseases and the complex pathogenesis cause diagnostic and therapeutic difficulties. Changes at the cellular and molecular level after Borrelia sp. infection remain still poorly understood. Therefore, the present study focused on the gene expression in human dermal fibroblasts in differentiation of infection with Borrelia garinii, Borrelia afzelii and Borrelia burgdorferi sensu stricto spirochetes.