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  • Neptunomyces aureus gen. et sp. nov. (Didymosphaeriaceae, Pleosporales) isolated from algae in Ria de Aveiro, Portugal
    Publication . Gonçalves, Micael F. M.; Vicente, Tânia F. L.; Esteves, Ana C.; Alves, Artur
    A collection of fungi was isolated from macroalgae of the genera Gracilaria, Enteromorpha and Ulva in the estuary Ria de Aveiro in Portugal. These isolates were characterized through a multilocus phylogeny based on ITS region of the ribosomal DNA, beta-tubulin (tub2) and translation elongation factor 1 alpha (tef1-a) sequences, in conjunction with morphological and physiological data. These analyses showed that the isolates represented an unknown fungus for which a new genus, Neptunomyces gen. nov. and a new species, Neptunomyces aureus sp. nov. are proposed. Phylogenetic analyses supported the affiliation of this new taxon to the family Didymosphaeriaceae. Copyright Micael F.M. Gonçalves et al.
  • A multi-omics analysis of the grapevine pathogen Lasiodiplodia theobromae reveals that temperature affects the expression of virulence- and pathogenicity-related genes
    Publication . Félix, Carina; Meneses, Rodrigo; Gonçalves, Micael F. M.; Tilleman, Laurentijn; Duarte, Ana S.; Jorrín-Novo, Jesus V.; Peer, Yves Van de; Deforce, Dieter; Nieuwerburgh, Filip Van; Esteves, Ana C.; Alves, Artur
    Lasiodiplodia theobromae (Botryosphaeriaceae, Ascomycota) is a plant pathogen and human opportunist whose pathogenicity is modulated by temperature. The molecular effects of temperature on L. theobromae are mostly unknown, so we used a multi-omics approach to understand how temperature affects the molecular mechanisms of pathogenicity. The genome of L. theobromae LA-SOL3 was sequenced (Illumina MiSeq) and annotated. Furthermore, the transcriptome (Illumina TruSeq) and proteome (Orbitrap LC-MS/MS) of LA-SOL3 grown at 25 °C and 37 °C were analysed. Proteins related to pathogenicity (plant cell wall degradation, toxin synthesis, mitogen-activated kinases pathway and proteins involved in the velvet complex) were more abundant when the fungus grew at 25 °C. At 37 °C, proteins related to pathogenicity were less abundant than at 25 °C, while proteins related to cell wall organisation were more abundant. On the other hand, virulence factors involved in human pathogenesis, such as the SSD1 virulence protein, were expressed only at 37 °C. Taken together, our results showed that this species presents a typical phytopathogenic molecular profile that is compatible with a hemibiotrophic lifestyle. We showed that L. theobromae is equipped with the pathogenesis toolbox that enables it to infect not only plants but also animals.
  • Dual RNA sequencing of vitis vinifera during lasiodiplodia theobromae infection unveils host–pathogen interactions
    Publication . Gonçalves, Micael F. M.; Nunes, Rui B.; Tilleman, Laurentijn; Peer, Yves Van De; Deforce, Dieter; Nieuwerburgh, Filip Van; Esteves, Ana C.; Alves, Artur
    Lasiodiplodia theobromae is one of the most aggressive agents of the grapevine trunk disease Botryosphaeria dieback. Through a dual RNA-sequencing approach, this study aimed to give a broader perspective on the infection strategy deployed by L. theobromae, while understanding grapevine response. Approximately 0.05% and 90% of the reads were mapped to the genomes of L. theobromae and Vitis vinifera, respectively. Over 2500 genes were significantly differentially expressed in infected plants after 10 dpi, many of which are involved in the inducible defense mechanisms of grapevines. Gene expression analysis showed changes in the fungal metabolism of phenolic compounds, carbohydrate metabolism, transmembrane transport, and toxin synthesis. These functions are related to the pathogenicity mechanisms involved in plant cell wall degradation and fungal defense against antimicrobial substances produced by the host. Genes encoding for the degradation of plant phenylpropanoid precursors were up-regulated, suggesting that the fungus could evade the host defense response using the phenylpropanoid pathway. The up-regulation of many distinct components of the phenylpropanoid pathway in plants supports this hypothesis. Moreover, genes related to phytoalexin biosynthesis, hormone metabolism, cell wall modification enzymes, and pathogenesis-related proteins seem to be involved in the host responses observed. This study provides additional insights into the molecular mechanisms of L. theobromae and V. vinifera interactions.
  • Three new species of Neocamarosporium isolated from saline environments: N. aestuarinum sp. nov., N. endophyticum sp. nov. and N. halimiones sp. nov.
    Publication . Gonçalves, M. F. M.; Aleixo, A.; Vicente, T. F. L.; Esteves, A. C.; Alves, A.
    Neocamarosporium species are typically halotolerant, being commonly found in saline environments like saline water, hypersaline soils and especially in association with halophytes. Several isolates were obtained from saline water, dead leaves of the seaweed Zostera noltii and live tissues of the halophyte Halimione portulacoides. Phylogenetic analysis based on ITS sequence data placed these isolates into three clades within the genus Neocamarosporium distinct from the currently known species. Isolates from each clade showed clear differences in conidial morphology. Three new species N. aestuarinum sp. nov., N. endophyticum sp. nov. and N. halimiones sp. nov. are described and illustrated. Our results show that the salt marsh plant H. portulacoides harbours a high diversity of Neocamarosporium species.
  • Unveiling biological activities of marine fungi: the effect of sea salt
    Publication . Gonçalves, Micael F. M.; Paço, Ana; Escada, Luís F.; Albuquerque, Manuela S. F.; Pinto, Carlos A.; Saraiva, Jorge A.; Duarte, Ana Sofia; Rocha-Santos, Teresa A. P.; Esteves, Ana Cristina; Alves, Artur
    There is an urgent need for new substances to overcome current challenges in the health sciences. Marine fungi are known producers of numerous compounds, but the manipulation of growth conditions for optimal compound production can be laborious and time-consuming. In Portugal, despite its very long coastline, there are only a few studies on marine fungi. From a collection of Portuguese marine fungi, we screened for antimicrobial, antioxidant, enzymatic, and cytotoxic activities. Mycelia aqueous extracts, obtained by high pressure-assisted extraction, and methanolic extracts of culture media showed high antioxidant, antimicrobial, and cytotoxic activities. The mycelium extracts of Cladosporium rubrum showed higher antioxidant potential compared to extracts from other fungi. Mycelia and culture media extracts of Aspergillus affinis and Penicillium lusitanum inhibited the growth of Staphylococcus aureus, Kocuria rhizophila, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa, including multiresistant strains. Penicillium lusitanum and Trichoderma aestuarinum inhibited the growth of clinical strains of Candida albicans, C. glabrata, C. parapsilosis, and C. tropicalis. All extracts from culture media were cytotoxic to Vero cells. Sea salt induced alterations in the mycelium's chemical composition, leading to different activity profiles.