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Summary: Plant‐tissue‐colonizing fungi fine‐tune the deconstruction of plant‐cell walls (PCW) using different sets of enzymes according to their lifestyle. However, some of these enzymes are conserved among fungi with dissimilar lifestyles. We identified genes from Glycoside Hydrolase family GH131 as commonly expressed during plant‐tissue colonization by saprobic, pathogenic and symbiotic fungi. By searching all the publicly available genomes, we found that GH131‐coding genes were widely distributed in the Dikarya subkingdom, except in Taphrinomycotina and Saccharomycotina, and in phytopathogenic Oomycetes, but neither other eukaryotes nor prokaryotes. The presence of GH131 in a species was correlated with its association with plants as symbiont, pathogen or saprobe. We propose that GH131‐family expansions and horizontal‐gene transfers contributed to this adaptation. We analysed the biochemical activities of GH131 enzymes whose genes were upregulated during plant‐tissue colonization in a saprobe (Pycnoporus sanguineus), a plant symbiont (Laccaria bicolor) and three hemibiotrophic‐plant pathogens (Colletotrichum higginsianum, C. graminicola, Zymoseptoria tritici). These enzymes were all active on substrates with β‐1,4, β‐1,3 and mixed β‐1,4/1,3 glucosidic linkages. Combined with a cellobiohydrolase, GH131 enzymes enhanced cellulose degradation. We propose that secreted GH131 enzymes unlock the PCW barrier and allow further deconstruction by other enzymes during plant tissue colonization by symbionts, pathogens and saprobes. [ABSTRACT FROM AUTHOR]

Summary: Monoterpenes are the most prevalent compounds found in essential oils. They exhibit inhibitory actions against phytopathogenic postharvest fungi. Direct application limits their effectiveness due to their instability, high volatility, hydrophobicity and susceptibility to degradation. Encapsulation systems using metal–organic frameworks (MOFs) have been developed to maximise their use. In this study, four protocols were shown to encapsulate thymol and limonene in porous solids, such as ZIF‐8, UiO‐66‐(COOH)2 and zeolite 13X. Vapourisation and diffusion at 60 °C for 16 h was found to be the most efficient encapsulation process. A larger amount of thymol than limonene was loaded in the porous solids. Thymol released from MOFs slowed down the growth of Colletotrichum musae by up to 6 days at 25 °C. There was a sustained release of thymol even beyond the period of maximum fungal growth. This proof‐of‐concept study revealed the potential utility of MOFs as carriers of thymol against postharvest fungi. [ABSTRACT FROM AUTHOR]

Jicaro seeds ( Crescentia alata ) are widely consumed in Central America, primarily as a popular tasty and nutritious beverage called “horchata”. Seeds are roasted to develop a specific aroma through a process that has never been explored. Volatile compounds, extracted from raw and roasted jicaro seeds (140 °C for 140 s) by SAFE (Solvent Assisted Flavor Evaporation), were analyzed by Gas Chromatography/Mass Spectrometry (GC/MS). Twenty-seven volatile compounds were isolated, among which, ethyl-2-methylbutyrate was designated by olfactometry as providing the characteristic jicaro note (0.16 and 0.47 mg/kg dry basis (d.b.) in raw and roasted seeds, respectively). The release of volatile compounds from the Maillard reaction, such as pyrazines, and the increase of ethyl-2-methylbutyrate after roasting, exhausted the pleasant jicaro aroma. This mild roasting process had a slight impact on polyphenol, fructose and free amino acid contents, in agreement with the Maillard reaction. Confocal microscopy showed the coalescence of lipids in roasted jicaro seeds, which might explain the higher extracted fat content. [ABSTRACT FROM AUTHOR]

Background: Transposable Elements (TEs) are key components that shape the organization and evolution of genomes. Fungi have developed defense mechanisms against TE invasion such as RIP (Repeat-Induced Point mutation), MIP (Methylation Induced Premeiotically) and Quelling (RNA interference). RIP inactivates repeated sequences by promoting Cytosine to Thymine mutations, whereas MIP only methylates TEs at C residues. Both mechanisms require specific cytosine DNA Methyltransferases (RID1/Masc1) of the Dnmt1 superfamily. Results: We annotated TE sequences from 10 fungal genomes with different TE content (1-70%). We then used these TE sequences to carry out a genome-wide analysis of C to T mutations biases. Genomes from either Ascomycota or Basidiomycota that were massively invaded by TEs (Blumeria, Melampsora, Puccinia) were characterized by a low frequency of C to T mutation bias (10-20%), whereas other genomes displayed intermediate to high frequencies (25-75%). We identified several dinucleotide signatures at these C to T mutation sites (CpA, CpT, and CpG). Phylogenomic analysis of fungal Dnmt1 MTases revealed a previously unreported association between these dinucleotide signatures and the presence/absence of sub-classes of Dnmt1. Conclusions: We identified fungal genomes containing large numbers of TEs with many C to T mutations associated with species-specific dinucleotide signatures. This bias suggests that a basic defense mechanism against TE invasion similar to RIP is widespread in fungi, although the efficiency and specificity of this mechanism differs between species. Our analysis revealed that dinucleotide signatures are associated with the presence/absence of specific Dnmt1 subfamilies. In particular, an RID1-dependent RIP mechanism was found only in Ascomycota. [ABSTRACT FROM AUTHOR]

The article discusses the carryless arithmetic calculation of modulus (mod) 10. It provides the prime number sequence generated from carryless square by presenting the fabled residents of Carryless Islanders as an example. It mentions the importance of algebra in understanding the concept of carryless arithmetic and the complication brought by zero-divisors. It also honors the contribution of mathematician Martin Gardner in carryless arithmetic.

Abstract: Mango fruit (Mangifera indica L.), cv. ‘Cogshall’, ‘Kent’ and ‘Keitt’ were harvested at different maturities (61–115d past flowering and 80–307averageg fresh weight for ‘Cogshall’) and at different sizes (364–1563 and 276–894averageg fresh weight for ‘Keitt’ and ‘Kent’, respectively). Immediately after harvest (green) or after 1 week of ripening at room temperature (ripe), fruit were homogenized or left intact and evaluated by electronic nose (enose) or by gas chromatography (GC) for aroma and other volatiles as well as for soluble solids and acids. Volatile data from the different harvest maturities and ripening stages were discriminated by using multivariate statistics (discriminant factor analysis). Both the enose and GC were able, in most cases, to separate fruit from different harvest maturities, especially for ‘Cogshall’ mangoes, at both the green and ripe stages as well as discriminate green from ripe fruit and fruit from the different varieties within a maturity stage. Solids and acids data indicated that later harvest maturities resulted in sweeter fruit and later-harvested fruit had a different volatile profile from earlier-harvested fruit. Mango fruit volatiles may be useful as maturity markers to determine optimal harvest maturity for mango fruit that results in full quality upon ripening. [Copyright &y& Elsevier]

BACKGROUND: Citrus juices can be cold‐concentrated by crossflow microfiltration (CMF) in order to obtain functional foods enriched in carotenoids, flavonoids and pectins. The work aimed to characterize the organoleptic quality of this type of micronutrient‐dense foods through their aroma profile and sensory analysis. Two citrus concentrates with and without a diafiltration step were compared. RESULTS: Both citrus products were very different, linked to aroma compound, sugar and organic acid contents. Due to its sugar/acidity balance and its better aromatic profile responsible for the citrus–floral flavour, the concentrate without diafiltration was preferred by the sensory panel. Thanks to a simple transfer model, we showed that retention of volatiles clearly varied from one aroma compound to another. The terpene hydrocarbons were the most retained by the membrane during CMF, probably because they were strongly associated with insoluble solids by adsorption. CONCLUSION: Even though the process modified their organoleptic profiles, both citrus‐based products were well rated and can be consumed directly as pleasant functional drinks. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Seeds of Parkia biglobosa, also called African locust bean seeds (ALBSs), are used to produce a condiment by subjecting them to cooking, alkaline fermentation, and drying. The objective of this work was to monitor the evolution of the composition of ALBS during spontaneous fermentation. Results showed that the seeds at initial time contained mainly proteins (45%) and lipids (36%). During fermentation, the conversion of this initial composition took place to produce ammonium, free amino acids, and short‐chain fatty acids (SCFAs) that accounted for 2%, 10%, and 1.5% dry basis, respectively, which explains the typical flavor of fermented ALBS. This release was also concomitant with biogenic amine production. Along with ammonium and SCFA release, pyrazines were the major volatile organic compounds. Composition modulation was well represented by a Verhulst equation in which the dynamic could be modified by the initial composition of the seed, the pre‐cooking step, and the fermentation conditions (temperature and aeration). Practical applications: For nutritional and sustainability reasons, re‐integration of vegetable in general and legumes, in particular in our diet, is a current trend. However, only dish that are appealing to consumers are concretely adopted. Fermentation of legumes is interesting in more than one way. It does not involve heat, so thermolabile molecules can be preserved and the financial and energetic costs are low. Biological interesting molecules are produced from the metabolism of microorganisms, and among them, volatile organic compounds that contribute to enhance the flavor of legume dishes. Soumbala is a meal and/or condiment obtained from the fermentation of African locust bean (Parkia biglobosa) seeds (ALBSs), a legume widely spread in west Africa. The final typical sensory properties are known to be due to the alkaline fermentation step by Bacillus species. This paper presents the kinetics of release of various compounds during spontaneous fermentation that may impact the sensory and nutritional properties of the final product. More precisely, the dynamic of the production of free amino acids, free fatty acids, volatile compounds, and biogenic amines are presented and discussed to give insights into the succession of important reactions to control the sensory and nutritional qualities of fermented ALBS (FALBS). This paper shows that further research are necessary to better understand and control the quality of not only FALBS but also similar protein‐rich legumes to modulate the quality of the final products. [ABSTRACT FROM AUTHOR]

Crown rot is an economically important postharvest disease of 'Cavendish' banana fruit caused by a complex of phytopathogenic fungi including Colletotrichum musae. The sustained release of bioactive compounds, such as thymol, encapsulated in porous materials has been studied for applications in postharvest fruit treatments. The release concentrations of thymol in its vapor phase, its evolution, and its impact on fruit preservation, or damage, have rarely been reported. In this study, an 11-d in vivo assay at 14 °C clearly demonstrated the contrasting effects of thymol vapor on banana fruit internal crown rot and phytotoxicity. Thymol vapor achieved by sublimation reduced necrosis in the crown from 40 % to 4 %. However, it triggered phytotoxicity, which caused damage to the fruit peel. Metal-organic frameworks (MOFs), in this case ZIF-8, UiO-66-(COOH) 2 and zeolite 13X enabled the sustained and controlled release of thymol. When encapsulated in ZIF-8, thymol had a release rate approximately 200 times slower than its sublimation rate at 30 °C. Despite the slower release kinetics, thymol released from ZIF-8 achieved concentrations that reduced internal crown rot, to the same extent as thymol sublimation. Moreover, the controlled release minimized phytotoxicity. [Display omitted] • ZIF-8, UiO-66-(COOH) 2 and zeolite 13X enabled sustained release of thymol. • Thymol release from ZIF-8 was 200 times slower than thymol sublimation. • Controlled release from ZIF-8 reduced internal crown rot and minimized phytotoxicity. [ABSTRACT FROM AUTHOR]

Information about several topics discussed during the "22nd New Phytologist Symposium: Effectors in Plant-Microbe Interactions" which was held in Versailles, France in September 2009 is presented. The symposium brought together scientists from across the globe who examined the plant-microbe interactions over pathosystems. The bacterial effectors were presented by Guy Cornelis, Jim Alfano, and Natalia Requena.

Pyricularia oryzae (syn. Magnaporthe oryzae), is a filamentous ascomycete that causes a major disease called blast on cereal crops, as well as on a wide variety of wild and cultivated grasses. Blast diseases have a tremendous impact worldwide particularly on rice and on wheat, where the disease emerged in South America in the 1980s, before spreading to Asia and Africa. Its economic importance, coupled with its amenability to molecular and genetic manipulation, have inspired extensive research efforts aiming at understanding its biology and evolution. In the past 40 years, this plant‐pathogenic fungus has emerged as a major model in molecular plant–microbe interactions. In this review, we focus on the clarification of the taxonomy and genetic structure of the species and its host range determinants. We also discuss recent molecular studies deciphering its lifecycle. Taxonomy: Kingdom: Fungi, phylum: Ascomycota, sub‐phylum: Pezizomycotina, class: Sordariomycetes, order: Magnaporthales, family: Pyriculariaceae, genus: Pyricularia. Host range: P. oryzae has the ability to infect a wide range of Poaceae. It is structured into different host‐specialized lineages that are each associated with a few host plant genera. The fungus is best known to cause tremendous damage to rice crops, but it can also attack other economically important crops such as wheat, maize, barley, and finger millet. Disease symptoms: P. oryzae can cause necrotic lesions or bleaching on all aerial parts of its host plants, including leaf blades, sheaths, and inflorescences (panicles, spikes, and seeds). Characteristic symptoms on leaves are diamond‐shaped silver lesions that often have a brown margin and whose appearance is influenced by numerous factors such as the plant genotype and environmental conditions. USEFUL WEBSITESResourcesURLGenomic data repositorieshttp://genome.jouy.inra.fr/gemo/Genomic data repositorieshttp://openriceblast.org/Genomic data repositorieshttp://openwheatblast.net/Genome browser for fungi (including P. oryzae)http://fungi.ensembl.org/index.htmlComparative genomics databasehttps://mycocosm.jgi.doe.gov/mycocosm/homeT‐DNA mutant databasehttp://atmt.snu.kr/T‐DNA mutant databasehttp://www.phi‐base.org/SNP and expression datahttps://fungidb.org/fungidb/app/ [ABSTRACT FROM AUTHOR]

Background: The fruity aromatic bouquet of coffee has attracted recent interest to differentiate high value market produce as specialty coffee. Although the volatile compounds present in green and roasted coffee beans have been extensively described, no study has yet linked varietal molecular differences to the greater abundance of specific substances and support the aroma specificity of specialty coffees. Results: This study compared four Arabica genotypes including one, Geisha Especial, suggested to generate specialty coffee. Formal sensory evaluations of coffee beverages stressed the importance of coffee genotype in aroma perception and that Geisha Especial-made coffee stood out by having fine fruity, and floral, aromas and a more balanced acidity. Comparative SPME–GC–MS analyses of green and roasted bean volatile compounds indicated that those of Geisha Especial differed by having greater amounts of limonene and 3-methylbutanoic acid in agreement with the coffee cup aroma perception. A search for gene ontology differences of ripening beans transcriptomes of the four varieties revealed that they differed by metabolic processes linked to terpene biosynthesis due to the greater gene expression of prenyl-pyrophosphate biosynthetic genes and terpene synthases. Only one terpene synthase (CaTPS10-like) had an expression pattern that paralleled limonene loss during the final stage of berry ripening and limonene content in the studied four varieties beans. Its functional expression in tobacco leaves confirmed its functioning as a limonene synthase. Conclusions: Taken together, these data indicate that coffee variety genotypic specificities may influence ripe berry chemotype and final coffee aroma unicity. For the specialty coffee variety Geisha Especial, greater expression of terpene biosynthetic genes including CaTPS10-like, a limonene synthase, resulted in the greater abundance of limonene in green beans, roasted beans and a unique citrus note of the coffee drink. [ABSTRACT FROM AUTHOR]

The rice blast fungus Magnaporthe oryzae differentiates specialized cells called appressoria that are required for fungal penetration into host leaves. In this study, we identified the novel basic leucine zipper (bZIP) transcription factor BIP1 (B-ZIP Involved in Pathogenesis-1) that is essential for pathogenicity. BIP1 is required for the infection of plant leaves, even if they are wounded, but not for appressorium-mediated penetration of artificial cellophane membranes. This phenotype suggests that BIP1 is not implicated in the differentiation of the penetration peg but is necessary for the initial establishment of the fungus within plant cells. BIP1 expression was restricted to the appressorium by both transcriptional and post-transcriptional control. Genome-wide transcriptome analysis showed that 40 genes were down regulated in a BIP1 deletion mutant. Most of these genes were specifically expressed in the appressorium. They encode proteins with pathogenesis-related functions such as enzymes involved in secondary metabolism including those encoded by the ACE1 gene cluster, small secreted proteins such as SLP2, BAS3, BAS4, and AVR-Pi9 effectors, as well as plant cuticle and cell wall degrading enzymes. Interestingly, this BIP1 network is different from other known infection-related regulatory networks, highlighting the complexity of gene expression control during plant-fungal interactions. Promoters of BIP1-regulated genes shared a GCN4/bZIP-binding DNA motif (TGACTC) binding in vitro to BIP1. Mutation of this motif in the promoter of MGG_08381.7 from the ACE1 gene cluster abolished its appressorium-specific expression, showing that BIP1 behaves as a transcriptional activator. In summary, our findings demonstrate that BIP1 is critical for the expression of early invasion-related genes in appressoria. These genes are likely needed for biotrophic invasion of the first infected host cell, but not for the penetration process itself. Through these mechanisms, the blast fungus strategically anticipates the host plant environment and responses during appressorium-mediated penetration. Author summary: The identification of gene regulatory networks controlling pathogenicity is a major research goal for understanding plant infection and for developing new strategies for disease control. Rice is the staple food for half the world's population, but its cultivation is threatened by the rice blast fungus Magnaporthe oryzae that causes severe yield losses. This fungus can breach intact plant leaves using specialized cells called appressoria. Here, we have identified in a pathogenicity mutant screen using random insertional mutagenesis, the novel M. oryzae bZIP transcription factor BIP1 that is essential for the infection. BIP1 is not implicated in the development of appressoria or the subsequent penetration of host leaves, but is necessary for the initial establishment of the fungus within plant cells. BIP1 orchestrates the expression of a unique set of early invasion-related genes within appressoria, encoding secreted effectors, enzymes, secondary metabolism-related enzymes, and signaling membrane receptors. Our experimental data suggest that BIP1 controls their expression by interacting directly with a TGACTC motif present in their promoters. Remarkably distinct from other known pathogenicity networks, the BIP1 regulatory network underscores the intricate control of fungal gene expression during infection. BIP1 seems to prepare M. oryzae for early biotrophic growth during appressorium-mediated penetration. [ABSTRACT FROM AUTHOR]

Summary: Molecular plant–fungal interaction studies have mainly focused on small secreted protein effectors. However, accumulating evidence shows that numerous fungal secondary metabolites are produced at all stages of plant colonization, especially during early asymptomatic/biotrophic phases. The discovery of fungal small RNAs targeting plant transcripts has expanded the fungal repertoire of nonproteinaceous effectors even further. The challenge now is to develop specific functional methods to fully understand the biological roles of these effectors. Studies on fungal extracellular vesicles are also needed because they could be the universal carriers of all kinds of fungal effectors. With this review, we aim to stimulate the nonproteinaceous effector research field to move from descriptive to functional studies, which should bring a paradigm shift in plant–fungal interactions. [ABSTRACT FROM AUTHOR]

Abstract Cocoa quality depends on several parameters, such as cocoa variety, environmental growth conditions, cultivation technique, and post-harvest treatments applied to coca beans. In this work, we studied the impact of cocoa post-harvest processing on both microbial communities structure and volatile composition. Cocoa beans samples were fermented in wooden boxes in Ivory Coast at different time intervals with turning and without turning, and derived from pods stored for two different duration times. Cocoa beans were analyzed using a molecular fingerprinting method (PCR-DGGE) in order to detect variations in microbial communities' structure; this global analysis was coupled to SPME-GC–MS for assessing cocoa volatile profiles. The results showed that the main parameter that influenced microbial communities structure was fermentation time, followed by turning, whereas, pods storage duration had a minor impact. Similar results were obtained for aromatic profile, except for pods storage duration that significantly affected volatile compound production. Global statistical analysis using Canonical Correspondence Analysis (CCA), showed the relationship between microbial communities and volatile composition. Furthermore, this study allowed the identification of discriminating microbial and chemical markers of cocoa post-harvest processing. Graphical abstract Unlabelled Image Highlights • Cocoa volatile composition were highly affected by fermentation time followed by turning and pods storage. • Pods storage duration had a minor impact on cocoa microbial communities' structure. • A long fermentation coupled with turning and short pods storage produced a good cocoa aromatic quality. [ABSTRACT FROM AUTHOR]

Two fresh (fresh cubic pieces, fresh puree) and two dried (dried cubic pieces, dried powder) products were prepared from a homogenous mango fruit batch to obtain four samples differing in texture. The aromatic profiles were determined by SAFE extraction technique and GC–MS analysis. VOCs released during consumption were trapped by a retronasal aroma-trapping device (RATD) and analysed by GC–MS. Twenty-one terpenes and one ester were identified from the exhaled nose-space. They were amongst the major mango volatile compounds, 10 of which were already reported as being potential key flavour compounds in mango. The in vivo release of aroma compounds was affected by the matrix texture. The intact samples (fresh and dried cubic pieces) released significantly more aroma compounds than disintegrated samples (fresh puree, dried powder). The sensory descriptive analysis findings were in close agreement with the in vivo aroma release data regarding fresh products, in contrast to the dried products. [ABSTRACT FROM AUTHOR]

We report here a new application, CustomProteinSearch (CusProSe), whose purpose is to help users to search for proteins of interest based on their domain composition. The application is customizable. It consists of two independent tools, IterHMMBuild and ProSeCDA. IterHMMBuild allows the iterative construction of Hidden Markov Model (HMM) profiles for conserved domains of selected protein sequences, while ProSeCDA scans a proteome of interest against an HMM profile database, and annotates identified proteins using user-defined rules. CusProSe was successfully used to identify, in fungal genomes, genes encoding key enzyme families involved in secondary metabolism, such as polyketide synthases (PKS), non-ribosomal peptide synthetases (NRPS), hybrid PKS-NRPS and dimethylallyl tryptophan synthases (DMATS), as well as to characterize distinct terpene synthases (TS) sub-families. The highly configurable characteristics of this application makes it a generic tool, which allows the user to refine the function of predicted proteins, to extend detection to new enzymes families, and may also be applied to biological systems other than fungi and to other proteins than those involved in secondary metabolism. [ABSTRACT FROM AUTHOR]

High‐pressure homogenization (HPH) was applied within a range of 300 to 1000 bar for 2 to 8 cycles. At constant dry matter (6.2%), pulp mass increased from 3.7 to 8%, indicating a change in particle organization. D90 varied from 197 to 20 μm depending on the pressure and number of cycles. The aggregation of particles, then destruction of the aggregates depending on the number of cycles, explained viscosity behavior. HPH delayed phase separation by an average 28.5 h. Sedimentation velocity was 10 times higher at 8 cycles than at 3 cycles, at 1000 bar. At 1000 bar, browning was observed, resulting from Maillard reactions, and was linked to the furan‐2‐pentyl content (10‐fold higher) and a 45% loss of carotenoids. This study will help in understanding changes induced in mango nectar by HPH and will be of use in developing processing technologies to preserve mango‐based products. Novelty impact statement: This study provides some additional scientific indications for understanding the subtility of HPH impacts in stabilizing mango nectar. The optimum pressure treatment for delaying phase separation (1000 bar, 3–6 cycles), i.e., reducing particle size and forming adequate re‐aggregation, also causes a Maillard reaction (2‐fold color difference, 10‐fold furan increase, etc.), hence browning through an increase in local temperature. It will therefore be necessary to find a compromise to limit degradation reactions caused by the process, and to guarantee greater consumer acceptance (phase separation and sensory quality). [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Recent surveys conducted on Amazonian cocoa trees in their home range are a unique opportunity to assess the aromas, diversity and potential of the Ecuadorian Amazon to create new aromatic cocoa varieties. Our results reveal informations about the diversity and genesis of aromas in Ecuadorian fine cocoa. The great aromatic diversity could enrich cocoa flavour selection programmes and provide Amazonian populations with new income linked to aromatic varieties, which could lead to a 'grand cru' chocolate. Until now, breeding programmes have been mainly focused on improving characteristics for production, but in recent years cocoa quality has been increasingly examined to meet market expectations. Summary: Ecuador is known worldwide for its fine or flavour cocoa from the Nacional variety. Currently, farmers mainly grow the modern Nacional variety of cocoa trees (hybrids between the ancestral Nacional and Trinitario) while the ancestral Nacional variety tends to be neglected. In order to enlarge the genetic resources related to this ancestral variety, several surveys were carried out in its area of origin located in the South Ecuadorian Amazonia.The 202 trees resulting from these surveys were genotyped using GBS (Genotyping By Sequencing) markers and their dried‐fermented beans were characterised for both their aromatic volatile compounds and sensorial quality. A genome wide association study (GWAS) was carried out with the aim to study the genetic and biochemical bases of the aroma traits of this population and to better exploit them in breeding programmes.Some association areas and candidate genes related to spicy and woody aromas were found for the first time in Theobromacacao. Some association areas and candidate genes related to floral and fruity aromas common to other studies were identified.Our results support the hypothesis that aroma formation may be related to a defence reaction to biotic and abiotic stresses generated by the fermentation process. [ABSTRACT FROM AUTHOR]

Volatile compounds from fresh and dried mango were extracted by the solvent-assisted flavour evaporation ( SAFE) technique and analysed by GC- MS. Forty-one and fifty five volatile compounds were identified in fresh and dried mango, respectively. Monoterpenes, followed by sesquiterpenes, lactones and alcohols were the major compounds. Drying induced substantial losses of several compounds. The total amount of volatiles decreased by about 59%. These losses could be mainly attributed to the evaporation of the volatiles during drying, the extent of which seemed to increase with the hydrophobicity and Henry's law constant of the compounds. However, new compounds appeared and enrichment of some compounds was observed after drying. Limonene, β-myrcene, δ-3-carene, β-caryophyllene, γ-butyrolactone and 3-methylbutyl butanoate were found to be flavour contributors in both products on the basis of the odour activity values ( OAVs). Mesifuran displayed high OAV only in fresh fruit while hexanal and heptanal only in dried mango. [ABSTRACT FROM AUTHOR]

In this study we identified the l-arabinose-responsive regulator of Pyricularia oryzae that regulates l-arabinose release and catabolism. Previously we identified the Zn2Cys6 transcription factor ( TF), AraR, that has this role in the Trichocomaceae family (Eurotiales), but is absent in other fungi. Candidate Zn2Cys6 TF genes were selected according to their transcript profiles on l-arabinose. Deletion mutants of these genes were screened for their growth phenotype on l-arabinose. One mutant, named Δ ara1, was further analyzed. Our analysis demonstrated that Ara1 from P. oryzae is the functional analog of AraR from A. niger, while there is no significant sequence similarity between them. [ABSTRACT FROM AUTHOR]

Summary: Bananas are tropical fruits that are perishable and susceptible to fungal diseases, mainly caused by Colletotrichum musae. Antimicrobial emulsion‐based coating materials have been used extensively to inhibit the growth of these fungi and extend the shelf life of bananas. Targeted emulsion‐based film functionalities offer excellent mechanical, physicochemical and barrier properties and limit fungal growth kinetics. Antifungal compounds, such as essential oils or phenolic compounds, are added to emulsion‐based (wax/biopolymer) coatings to enhance their antimicrobial properties. This study set out to formulate a beeswax‐based emulsion for banana coatings using high‐pressure homogenisation (HPH) and hydrophilic food‐grade/organic coating materials. The particle size distribution, stability and mechanical properties of the film‐forming emulsions, water vapour and the oxygen permeabilities of the resulting coating were investigated. The most promising sucrose emulsions were tested as coatings on banana fruits to assess their efficacy against moisture and firmness loss during storage. Adding thymol (0.5% w/w) to the sucrose emulsions further enhanced the inhibition of Colletotrichum musae growth to its barest minimum of <20%. Emulsion stability was clearly enhanced using HPH while the best inhibition was obtained with a 20% diluted sucrose emulsion containing 0.5% thymol, with or without HPH. [ABSTRACT FROM AUTHOR]

Effects of cooking and drying on color, curcuminoids, essential oil, and aroma compounds of Curcuma longa L. were assessed. Sliced fresh turmeric rhizomes were air‐dried at 60°C directly or after cooking at 95°C for 3 or 90 min. Microscopic observations showed that curcuminoids and essential oil are located in different dedicated cells. Curcuminoids and essential oil of dried turmeric were both around 10% db. After processing, curcuminoids were dispersed throughout the matrix. Drastic cooking and drying operations decreased chromatic values more than smooth cooking. Cooking had no impact on curcuminoid and essential oil contents and slightly modified the aromatic profile of essential oils. Drying decreased the curcuminoid (<38%) and essential oil (<13%) contents. Turmeric starchy matrix preserves the curcuminoids and essential oil during the process. We recommend a preliminary smooth cooking step to reduce the drying time, save energy consumption and preserve turmeric quality. Novelty impact statement: Our study brings us to propose better practices for turmeric processing. A smooth cooking (95°C/3 min) before drying is recommended to preserve the quality of the turmeric as the curcuminoids and essential oil are preserved during cooking. This protection could be linked to the starchy structure of the turmeric matrix. [ABSTRACT FROM AUTHOR]

Two Neofusicoccumparvum isolates and a UV mutant were characterized for their phytotoxin production in vitro, their pathogenicity on grapevine, and their genome sequenced. The isolate Np-Bt67 produced high level of (-)-terremutin, but almost no (R)-mellein, and it was the most aggressive on grapevine, triggering apoplexy. Similar symptoms were not induced by purified (-)-terremutin. The isolate Bourgogne S-116 (Np-B) produced 3-fold less (-)-terremutin and high amounts of (R)-mellein, but it was less aggressive on grapevine than Np-Bt67. The UV9 mutant obtained from Np-B (NpB-UV9) no longer produced (-)-terremutin but overproduced (R)-mellein by 2.5-fold, and it was as pathogenic as its parent. NpB-UV9 differed from its parent by simple mutations in two genes (transcription factor UCR-NP2_6692, regulatory protein UCR-NP2_9007), not located neither near (R)-mellein, nor (-)-terremutin biosynthetic genes, but likely involved in the control of (-)-terremutin biosynthesis. Grapevine immunity was disturbed upon challenge with these pathogens or purified phytotoxins, leading to an upregulation of SA-dependent defenses, while (-)-terremutin interfered with host JA/ET-dependent defenses. Our results suggest that neither (-)-terremutin nor (R)-mellein alone is essential for the pathogenicity of N. parvum on grapevine, since isolate/mutant non-producing these toxins in vitro is pathogenic. However, these phytotoxins could play a quantitative role in the infection process. [ABSTRACT FROM AUTHOR]

A postharvest treatment based on citric acid and chitosan was tested on two litchi cultivars of different provenance. Its effects on the activities of polyphenol oxidase (PPO), peroxidase (POD) and anthocyanase and on the anthocyanin content of the pericarp were measured as factors responsible for pericarp browning. The red colour of the pericarp was measured during storage of the fruit. The major anthocyanins present in both cultivars were cyanidin-3-rutinoside and cyanidin-3-glucoside. Although the concentration of cyanidin-3-rutinoside was 64% lower in the cultivar Kwai may (Guiwei) than in Wai chee (Huaizhi), this component represented more than 90% of total anthocyanins in both cultivars. The activity of PPO was six times greater in Kwai may than in Wai chee and the activity of POD was 30-times greater. The activity of POD was greater than that of PPO in both cultivars. The two cultivars, which differ in anthocyanin and oxidative enzyme compositions, responded differently to the acid and chitosan treatment, with the result that the red colour of Kwai may was better preserved during storage than that of Wai chee. This technique could be a future replacement for current sulphur treatments used to treat litchis transported by sea. [Copyright &y& Elsevier]

Abstract: Chimeric retrogenes, found in mammalian and fungal genomes, are bipartite elements composed of DNA copies of cellular transcripts either directly fused to each other or fused to the 3′ part of a LINE retrotransposon. These cellular transcripts correspond to messenger RNAs, ribosomal RNAs, small nuclear RNAs and 7SL RNA. The chimeras are likely formed by RNA template switches during reverse transcription of LINE elements by their retrotranspositional machinery. The 5′ part of chimeras are copies of nucleolar RNAs, suggesting that the nucleolus plays a significant role in LINE retrotransposition. RNAs from the nucleolus might have protective function against retroelement invasion or, alternatively, the nucleolus may be required for retrotranspositional complex assembly and maturation. These hypotheses will be discussed in this review. [Copyright &y& Elsevier]

The ability of plant pathogenic fungi to infect their host depends on successful penetration into plant tissues. This process often involves the differentiation of a specialized cell, the appressorium. Signalling pathways required for appressorium formation are conserved among fungi. However, the functions involved in appressorium maturation and penetration peg formation are still poorly understood. Recent studies have shown that Pls1 tetraspanins control an appressorial function required for penetration into host plants and are likely conserved among plant pathogenic fungi. Tetraspanins are small membrane proteins widely distributed among ascomycetes and basidiomycetes defining two distinct families; Pls1 tetraspanins are found in both ascomycetes and basidiomycetes and Tsp2 tetraspanins are specific to basidiomycetes. Both fungal tetraspanins families have similar secondary structures shared with animal tetraspanins. Pls1 tetraspanins are present as single genes in genomes of ascomycetes, allowing a unique opportunity to study their function in appressorium mediated penetration. Experimental evidence suggests that Pls1 tetraspanins are required for the formation of the penetration peg at the base of the appressorium, probably through re-establishing cell polarity. [ABSTRACT FROM AUTHOR]

Rice, as a widely and intensively cultivated crop, should be a target fur parasite host shills and a source for shifts to co-occurring weeds. Magnaporthe oryzae, of the M. grisea species complex, is the most important fungal pathogen of rice, with a high degree of host specificity. On the basis of 10 loci from six of its seven linkage groups, 37 multilocus haplotypes among 497 isolates of M. oryzae from rice and other grasses were identified. Phylogenetic relationships among isolates from rice (Oryza sativa), millet (Setaria spp.), cutgrass (Leersia hexandra), and torpedo grass (Panicum repens) were predominantly tree like, consistent with a lack of recombination, but from other hosts were reticulate, consistent with recombination. The single origin of rice-infecting M. oryzae followed a host shift from a Setaria millet and was closely followed by additional shifts to weeds of rice, cutgrass, and torpedo grass. Two independent estimators of divergence time indicate that these host shifts predate the Green Revolution and could be associated with rice domestication. The rice-infecting lineage is characterized by high copy number of the transposable element MGR586 (Pot3) and, except in two haplotypes, by a loss of AVR-Co39. Both mating types have been retained in ancestral, well-distributed rice-infecting haplotypes 10 (mainly temperate) and 14 (mainly tropical), but only one mating type was recovered from several derived, geographically restricted haplotypes. There is evidence of a common origin of both ACE1 virulence genotypes in haplotype 14. Host-haplotype association is evidenced by low pathogenicity on hosts associated with other haplotypes. [ABSTRACT FROM AUTHOR]

Severe Acute Malnutrition (SAM) is still a public health issue in many low-income and middle-income countries. Its management has changed with the development of Ready-to-Use Therapeutic Foods (RUTF) that are energy-dense, lipid-based, micronutrient-enriched foods. The purpose of the present study was to define some aspects of the nutritional profile (in particular, lipid content, fatty acids profile, lipophilic vitamin content), oxidative status, and mycotoxin content of three RUTF products (of which two manufactured in Asia and one in Europe), at different time points during their storage. All RUTF displayed good lipid stability, with peroxide values < 10 meqO2/kg lipids, acidity index < 0.6 g/100 g lipids, and very low amounts of secondary oxidation volatile compounds. Only the one produced in Europe complied with the international recommendations on vitamin A and E contents. Lipid content ranged from 28.7 ± 0.5 to 41.2 ± 2.4 g/100 g. Oleic acid, palmitic acid, and linoleic acid (47.2 ± 7.4%, 26.8 ± 2.1%, and 12.4 ± 3.9% of total lipids, respectively) were the main fatty acids. Only one of the samples made in Asia exceeded the regulatory limit of mycotoxins. The RUTF lipid phase was rather stable at ambient temperature from 9 to 12 months, and appropriate packaging may have contributed to a major stability. [ABSTRACT FROM AUTHOR]

Although sodium arsenite was widely used in Europe until its ban in 2003, its effects on microorganisms is not clearly understood. To improve our understanding of sodium arsenite curative effect on GTDs, grapevines displaying esca-foliar symptoms from different French regions (Alsace, Champagne, Languedoc) were treated or not with sodium arsenite, and analyzed for their wood microbiota. Using metabarcoding, we identified the fungal and bacterial taxa composition of microbiota colonizing woody trunk tissues. Large differences in fungal microbiota composition between treated and untreated grapevines were observed while no major impacts were observed on bacteria microbiota. The main fungal species detected in untreated necrotic woody tissues was Fomitiporia mediterranea (63–94%), a fungal pathogen associated with esca. The relative abundance of this fungal species significantly decreased after sodium arsenite treatment in the three vineyards, in particular in white-rot necrotic tissues and their borders (−90%). F. mediterranea was the most sensitive to sodium arsenite among fungi from grapevine woody tissues. These results strongly suggest that the effect of sodium arsenite on GTDs is due to its ability to efficiently and almost specifically eliminate F. mediterranea from white-rot necrotic tissues, allowing saprobic fungi to colonize the tissues previously occupied by this pathogenic fungus. [ABSTRACT FROM AUTHOR]

Summary: Most of volatile flavour compounds occurred during the cocoa postharvest operations including pod storage and fermentation whom effects on these metabolites were aimed by the present study. Three different spontaneous fermentation treatments were performed on the farm, and the main isolated yeasts were identified using PCR‐DGGE technique. Fermented cocoa beans were solar‐dried, and their flavour compounds were identified using solid phase microextraction technique–gas chromatography–mass spectrometry. The main results showed that Pichia kudriavzevii was common yeast involved in the cocoa fermentation. Thirty flavour precursor compounds grouped into six chemical families including alcohols and pyrazines were identified in raw cocoa samples. ACP showed that short durations of pod storage and fermentation promote the formation of flavour precursors of cocoa. No spontaneous cocoa fermentation treatment influenced the occurrence of aroma compounds. The generation of flavour compounds depends only on the pod storage and the fermentative microorganisms of cocoa. [ABSTRACT FROM AUTHOR]

Summary: Esca, a major grapevine trunk disease in old grapevines, is associated with the colonization of woody tissues by a broad range of plant pathogenic fungi. To identify which fungal and bacterial species are involved in the onset of this disease, we analysed the microbiota from woody tissues of young (10‐year‐old) grapevines at an early stage of esca. Using meta‐barcoding, 515 fungal and 403 bacterial operational taxonomic units (OTUs) were identified in woody tissues. In situ hybridization showed that these fungi and bacteria co‐inhabited in grapevine woody tissues. In non‐necrotic woody tissues, fungal and bacterial microbiota varied according to organs and seasons but not diseased plant status. Phaeomoniella chlamydospora, involved in the Grapevine trunk disease, was the most abundant species in non‐necrotic tissues from healthy plants, suggesting a possible non‐pathogenic endophytic behaviour. Most diseased plants (70%) displayed cordons, with their central white‐rot necrosis colonized essentially by two plant pathogenic fungi (Fomitiporia mediterranea: 60%–90% and P. chlamydospora: 5%–15%) and by a few bacterial taxa (Sphingomonas spp. and Mycobacterium spp.). The occurrence of a specific association of fungal and bacterial species in cordons from young grapevines expressing esca‐foliar symptoms strongly suggests that that microbiota is involved in the onset of this complex disease. [ABSTRACT FROM AUTHOR]

Fusarium graminearum is one of the most destructive plant pathogens worldwide, causing fusarium head blight (FHB) on cereals. F. graminearum colonizes wheat plant surfaces with specialized unbranched hyphae called runner hyphae (RH), which develop multicelled complex appressoria called infection cushions (IC). IC generate multiple penetration sites, allowing the fungus to enter the plant cuticle. Complex infection structures are typical for several economically important plant pathogens, yet with unknown molecular basis. In this study, RH and IC formed on the surface of wheat paleae were isolated by laser capture microdissection. RNA‐Seq‐based transcriptomic analyses were performed on RH and IC and compared to mycelium grown in complete medium (MY). Both RH and IC displayed a high number of infection up‐regulated genes (982), encoding, among others, carbohydrate‐active enzymes (CAZymes: 140), putative effectors (PE: 88), or secondary metabolism gene clusters (SMC: 12 of 67 clusters). RH specifically up‐regulated one SMC corresponding to aurofusarin biosynthesis, a broad activity antibiotic. IC specifically up‐regulated 248 genes encoding mostly putative virulence factors such as 7 SMC, including the mycotoxin deoxynivalenol and the newly identified fusaoctaxin A, 33 PE, and 42 CAZymes. Furthermore, we studied selected candidate virulence factors using cellular biology and reverse genetics. Hence, our results demonstrate that IC accumulate an arsenal of proven and putative virulence factors to facilitate the invasion of epidermal cells. [ABSTRACT FROM AUTHOR]

An innovative process combining roasting and tempering was proposed to promote puffing and mechanical dehulling of jicaro seeds. Roasting was performed at three temperatures (120 °C, 140 °C, and 160 °C) and for six residence times (80–180 s). A previous seed tempering was performed at 15% moisture content for 24 h, by spraying the seeds with an amount of water calculated to reach the final moisture content of 15%. The following parameters were monitored as a function of time to optimize the roasting operation: percentage of open seeds, whiteness of cotyledons, and content of two volatile compounds, 2,5-dimethylpyrazine and ethyl-2-methylbutyrate which are considered as the key jicaro note. The optimal roasting was achieved at 160 °C for 150 s with 90% open seeds. The optimal mechanical dehulling was achieved after tempering the roasted seed at 10% moisture content with a yield of 75%. The lightness evolution followed a zero-order kinetic with an activation energy of 103 kJ mol −1 . Ethyl-2-methylbutyrate and 2,5-dimethylpyrazine increased with the temperature and period of roasting. [ABSTRACT FROM AUTHOR]

Deciphering the genetic bases of pathogen adaptation to its host is a key question in ecology and evolution. To understand how the fungus Magnaporthe oryzae adapts to different plants, we sequenced eight M. oryzae isolates differing in host specificity (rice, foxtail millet, wheat and goosegrass), and one Magnaporthe grisea isolate specific of crabgrass. Analysis of Magnaporthe genomes revealed small variation in genome sizes [39-43 Mb] and gene content [12,283-14,781 genes] between isolates. The whole set of Magnaporthe genes comprised 14,966 shared families, 63% of which included genes present in all the 9 M. oryzae genomes. The evolutionary relationships among Magnaporthe isolates were inferred using 6,878 single-copy orthologs. The resulting genealogy was mostly bifurcating among the different host-specific lineages, but reticulate inside the rice lineage. We detected traces of introgression from a non-rice genome in the rice reference 70-15 genome. Among M. oryzae isolates and host specific lineages, the genome composition in terms of frequencies of genes putatively involved in pathogenicity (effectors, secondary metabolism, cazome) was conserved. However, 529 shared families were found only in non-rice lineages, whereas the rice lineage possessed 86 specific families absent from the non-rice genomes. Our results confirmed that the host specificity of M. oryzae isolates was associated with a divergence between lineages without major gene flow and that, despite the strong conservation of gene families between lineages, adaptation to different hosts, especially to rice, was associated with the presence of a small number of specific gene families. [ABSTRACT FROM AUTHOR]

The present paper represents the second contribution in the Genera of Fungi series, linking type species of fungal genera to their morphology and DNA sequence data, and where possible, ecology. This paper focuses on 12 genera of microfungi, 11 of which the type species are neo- or epitypified here: Allantophomopsis (A. cytisporea, Phacidiaceae, Phacidiales, Leotiomycetes), Latorua gen. nov. (Latorua caligans, Latoruaceae, Pleosporales, Dothideomycetes), Macrodiplodiopsis (M. desmazieri, Macrodiplodiopsidaceae, Pleosporales, Dothideomycetes), Macrohilum (M. eucalypti, Macrohilaceae, Diaporthales, Sordariomycetes), Milospium ( M. graphideorum, incertae sedis, Pezizomycotina), Protostegia (P. eucleae, Mycosphaerellaceae, Capnodiales, Dothideomycetes), Pyricularia (P. grisea, Pyriculariaceae, Magnaporthales, Sordariomycetes), Robillarda (R. sessilis, Robillardaceae, Xylariales, Sordariomycetes), Rutola ( R. graminis, incertae sedis, Pleosporales, Dothideomycetes), Septoriella (S. phragmitis, Phaeosphaeriaceae, Pleosporales, Dothideomycetes), Torula ( T. herbarum, Torulaceae, Pleosporales, Dothideomycetes) and Wojnowicia (syn. of Septoriella, S. hirta, Phaeosphaeriaceae, Pleosporales, Dothideomycetes). Novel species include Latorua grootfonteinensis, Robillarda africana, R. roystoneae, R. terrae, Torula ficus, T. hollandica, and T. masonii spp. nov., and three new families: Macrodiplodiopsisceae, Macrohilaceae, and Robillardaceae. Authors interested in contributing accounts of individual genera to larger multi-authored papers to be published in IMA Fungus, should contact the associate editors listed for the major groups of fungi on the List of Protected Generic Names for Fungi (www.generaoffungi.org). [ABSTRACT FROM AUTHOR]

Studying essential genes in haploid fungi requires specific tools. Conditional promoter replacement (CPR) is an efficient method for testing gene essentiality. However, this tool requires promoters that can be strongly down-regulated. To this end, we tested the nitrate reductase promoters of Magnaporthe oryzae (pMoNIA1 ) and Zymoseptoria tritici ( pZtNIA1 ) for their conditional expression in Z . tritici . Expression of EGFP driven by pMoNIA1 or pZtNIA1 was induced on nitrate and down-regulated on glutamate (10-fold less than nitrate). Levels of differential expression were similar for both promoters, demonstrating that the Z . tritici nitrogen regulatory network functions with a heterologous promoter similarly to a native promoter. To establish CPR, the promoter of Z. tritici BGS1 , encoding a β-1,3-glucan synthase, was replaced by pZtNIA1 using targeted sequence replacement. Growth of pZtNIA1::BGS1 CPR transformants was strongly reduced in conditions repressing pZtNIA1 , while their growth was similar to wild type in conditions inducing pZtNIA1 . This differential phenotype demonstrates that BGS1 is important for growth in Z . tritici . In addition, in inducing conditions, pZtNIA1::BGS1 CPR transformants were hyper-sensitive to Calcofluor white, a cell wall disorganizing agent. Nitrate reductase promoters are therefore suitable for conditional promoter replacement in Z . tritici . This tool is a major step toward identifying novel fungicide targets. [ABSTRACT FROM AUTHOR]

Methionine is a sulfur amino acid standing at the crossroads of several biosynthetic pathways. In fungi, the last step of methionine biosynthesis is catalyzed by a cobalamine-independent methionine synthase (Met6, EC 2.1.1.14). In the present work, we studied the role of Met6 in the infection process of the rice blast fungus, Magnaporthe oryzae. To this end MET6 null mutants were obtained by targeted gene replacement. On minimum medium, MET6 null mutants were auxotrophic for methionine. Even when grown in presence of excess methionine, these mutants displayed developmental defects, such as reduced mycelium pigmentation, aerial hypha formation and sporulation. They also displayed characteristic metabolic signatures such as increased levels of cysteine, cystathionine, homocysteine, S-adenosylmethionine, S-adenosylhomocysteine while methionine and glutathione levels remained unchanged. These metabolic perturbations were associated with the over-expression of MgCBS1 involved in the reversed transsulfuration pathway that metabolizes homocysteine into cysteine and MgSAM1 and MgSAHH1 involved in the methyl cycle. This suggests a physiological adaptation of M. oryzae to metabolic defects induced by the loss of Met6, in particular an increase in homocysteine levels. Pathogenicity assays showed that MET6 null mutants were non-pathogenic on both barley and rice leaves. These mutants were defective in appressorium-mediated penetration and invasive infectious growth. These pathogenicity defects were rescued by addition of exogenous methionine and S-methylmethionine. These results show that M. oryzae cannot assimilate sufficient methionine from plant tissues and must synthesize this amino acid de novo to fulfill its sulfur amino acid requirement during infection. [ABSTRACT FROM AUTHOR]

Fungi have the capacity to cause devastating diseases of both plants and animals, causing significant harvest losses that threaten food security and human mycoses with high mortality rates. As a consequence, there is a critical need to promote development of new antifungal drugs, which requires a comprehensive molecular knowledge of fungal pathogenesis. In this review, we critically evaluate current knowledge of seven fungal organisms used as major research models for fungal pathogenesis. These include pathogens of both animals and plants; Ashbya gossypii , Aspergillus fumigatus , Candida albicans , Fusarium oxysporum , Magnaporthe oryzae , Ustilago maydis and Zymoseptoria tritici . We present key insights into the virulence mechanisms deployed by each species and a comparative overview of key insights obtained from genomic analysis. We then consider current trends and future challenges associated with the study of fungal pathogenicity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Magnaporthe oryzae Xlr1 (homolog of Aspergillus niger XlnR) does not significantly affect expression of xylanolytic genes. [•] Disruption of XLR1 in Magnaporthe oryzae results in a strong reduction in growth on D-xylose, but not on L-arabinose. [•] Disruption of the Magnaporthe oryzae XKI1 gene encoding D-xylulokinase abolishes growth on both D-xylose and L-arabinose. [ABSTRACT FROM AUTHOR]

Highlights: [•] The Magnaporthe oryzae genome contains a novel pentose reductase (PRD1), but no l-arabinose reductase. [•] PRD1 has similar activity to l-arabinose and d-xylose. [•] PRD1 is only present in a subset of filamentous fungi. [Copyright &y& Elsevier]

Effector proteins are key elements in plant-fungal interactions. The rice blast fungus Magnaporthe oryzae secretes numerous effectors that are suspected to be translocated inside plant cells. However, their cellular targets and the mechanisms of translocation are still unknown. Here, we have identified the open reading frame ( ORF3) corresponding to the M. oryzae avirulence gene AVR1- CO39 that interacts with the rice resistance gene Pi- CO39 and encodes a small secreted protein without homology to other proteins. We demonstrate that AVR1- CO39 is specifically expressed and secreted at the plant-fungal interface during the biotrophic phase of infection. Live-cell imaging with M. oryzae transformants expressing a translational fusion between AVR1- CO39 and the monomeric red fluorescent protein ( mRFP) indicated that AVR1- CO39 is translocated into the cytoplasm of infected rice cells. Transient expression of an AVR1- CO39 isoform without a signal peptide in rice protoplasts triggers a Pi- CO39-specific hypersensitive response, suggesting that recognition of AVR1- CO39 by the Pi- CO39 gene product occurs in the cytoplasm of rice cells. The native AVR1- CO39 protein enters the secretory pathway of rice protoplasts as demonstrated by the ER localization of AVR1- CO39: mRFP: HDEL translational fusions, and is correctly processed as shown by Western blotting. However, this secreted AVR1- CO39 isoform triggers a Pi- CO39-specific hypersensitive response and accumulates inside rice protoplasts as shown by Western blotting and localization of AVR1- CO39: mRFP translational fusions. This indicates that AVR1- CO39 is secreted by rice protoplasts and re-enters into the cytoplasm by unknown mechanisms, suggesting that translocation of AVR1- CO39 into rice cells occurs independently of fungal factors. [ABSTRACT FROM AUTHOR]

ABSTRACT The volatile compounds of bitter orange ( Citrus aurantium L.) products, essential oil (EO) and the heart cut (HC) of the distillate were detected and quantified using gas chromatography (GC) coupled with a mass spectrometer and flame ionization detector. The flavour compounds were characterized using GC-olfactometry by nine trained panellists by the frequency of detection method. In total, 53 molecules were detected in the EO and 40 in the HC. The EO was characterized by 19 major odour compounds (frequency of detection from 6/9 to 9/9) with different aromatic notes among which α-pinene (floral), octanal (green), limonene (citrus), linalool (floral), α-terpineol (indeterminate: 'ND', green), linalyl acetate (floral), ( E, E) or ( E, Z)-2,4-decadienal (frying), dodecanal (ND), caryophyllene (green) and an unknown compound ( IT = 1678, plastic note). The HC presented a complex mixture of several molecules in low concentrations, which characterize the bitter orange flavour. The HC was characterized by seven high FD odour compounds, three of them (myrcene, α-phellandrene, and limonene) with citrus and mint aromatic notes, and the other four (( Z)-linalool oxide, α-terpinolene, linalool and neral) with floral notes. The comparison of these two products brought to light that the overall process of maceration/distillation could induce the loss of 15 strong odours previously found in simple essential oil and characterized by plastic and metal notes. These results show that macerating-distilling bitter orange peels and EO makes it possible to select the most pleasant odour compounds while eliminating some off-odours present in the EO. This is the first time that the characterization of odour-active compounds has been carried out on bitter orange products. This valuable information could help for further investigation on process/product optimization. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Fungi inhabit every natural and anthropogenic environment on Earth. They have highly varied life-styles including saprobes (using only dead biomass as a nutrient source), pathogens (feeding on living biomass), and symbionts (co-existing with other organisms). These distinctions are not absolute as many species employ several life styles (e.g. saprobe and opportunistic pathogen, saprobe and mycorrhiza). To efficiently survive in these different and often changing environments, fungi need to be able to modify their physiology and in some cases will even modify their local environment. Understanding the interaction between fungi and their environments has been a topic of study for many decades. However, recently these studies have reached a new dimension. The availability of fungal genomes and development of postgenomic technologies for fungi, such as transcriptomics, proteomics and metabolomics, have enabled more detailed studies into this topic resulting in new insights. Based on a Special Interest Group session held during IMC9, this paper provides examples of the recent advances in using (post-)genomic approaches to better understand fungal interactions with their environments. [ABSTRACT FROM AUTHOR]

Powdery mildews are phytopathogens whose growth and reproduction are entirely dependent on living plant cells. The molecular basis of this life-style, obligate biotrophy, remains unknown. We present the genome analysis of barley powdery mildew, Blumeria graminis f.sp. hordei (Blumeria), as well as a comparison with the analysis of two powdery mildews pathogenic on dicotyledonous plants. These genomes display massive retrotransposon proliferation, genome-size expansion, and gene losses. The missing genes encode enzymes of primary and secondary metabolism, carbohydrate-active enzymes, and transporters, probably reflecting their redundancy in an exclusively biotrophic life-style. Among the 248 candidate effectors of pathogenesis identified in the Blumeria genome, very few (less than 10) define a core set conserved in all three mildews, suggesting that most effectors represent species-specific adaptations. [ABSTRACT FROM AUTHOR]

Magnaporthe oryzae is the most damaging fungal pathogen of rice (Oryza sativa). In this study, we characterized the TIG1 transducin β-like gene required for infectious growth and its interacting genes that are required for plant infection in this model phytopathogenic fungus. Tig1 homologs in yeast and mammalian cells are part of a conserved histone deacetylase (HDAC) transcriptional corepressor complex. The tig1 deletion mutant was nonpathogenic and defective in conidiogenesis. It had an increased sensitivity to oxidative stress and failed to develop invasive hyphae in plant cells. Using affinity purification and coimmunoprecipitation assays, we identified several Tig1-associated proteins, including two HDACs that are homologous to components of the yeast Set3 complex. Functional analyses revealed that TIG1 , SET3 , SNT1 , and HOS2 were core components of the Tig1 complex in M. oryzae. The set3 , snt1 , and hos2 deletion mutants displayed similar defects as those observed in the tig1 mutant, but deletion of HST1 or HOS4 had no detectable phenotypes. Deletion of any of these core components of the Tig1 complex resulted in a significant reduction in HDAC activities. Our results showed that TIG1 , like its putative yeast and mammalian orthologs, is one component of a conserved HDAC complex that is required for infectious growth and conidiogenesis in M. oryzae and highlighted that chromatin modification is an essential regulatory mechanism during plant infection. [ABSTRACT FROM AUTHOR]

Abstract: Essential oil samples of Cinnamosma fragrans from two regions in Madagascar, Tsaramandroso (38 samples) and Mariarano (30 samples), were analysed by GC/MS. Fifty-seven components were identified, accounting from 88.3% to 99.4% of the oils’ composition. The major components were linalool (72.5±23.3%) in Tsaramandroso and 1,8-cineole (47.3±10.2%) in Mariarano. Samples B8 (95.8% linalool) from Tsaramandroso and B143 (71.6% 1,8-cineole) from Mariarano containing the highest proportions of the two main components identified, were selected to determine antimicrobial activities against 10 microbial strains. Bacillus subtilis and Staphylococcus aureus were the most sensitive strains to both oils. Minimum inhibitory concentration (MIC) values were lower for B143 against all tested Gram-negative strains than pure 1,8-cineole. B8 showed higher MIC values than pure linalool against Salmonella typhimurium and Vibrio alginolyticus, and similar MIC values to linalool towards the other Gram-negative strains. Both essential oils exhibited higher MIC values towards Fusarium oxysporum than their respective pure major component. These results suggested the occurrence of synergism or antagonism effects between the different oil constituents. [Copyright &y& Elsevier]

Abstract: Mitogen-activated protein kinase (MAPK) cascades and the calcium–calcineurin pathway control fundamental aspects of fungal growth, development and reproduction. Core elements of these signalling pathways are required for virulence in a wide array of fungal pathogens of plants and mammals. In this review, we have used the available genome databases to explore the structural conservation of three MAPK cascades and the calcium–calcineurin pathway in ten different fungal species, including model organisms, plant pathogens and human pathogens. While most known pathway components from the model yeast Saccharomyces cerevisiae appear to be widely conserved among taxonomically and biologically diverse fungi, some of them were found to be restricted to the Saccharomycotina. The presence of multiple paralogues in certain species such as the zygomycete Rhizopus oryzae and the incorporation of new functional domains that are lacking in S. cerevisiae signalling proteins, most likely reflect functional diversification or adaptation as filamentous fungi have evolved to occupy distinct ecological niches. [Copyright &y& Elsevier]