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Scientific communication is facilitated by a data-driven, scientifically sound taxonomy that considers the end-user's needs and established successful practice. In 2013, the Fusarium community voiced near unanimous support for a concept of Fusarium that represented a clade comprising all agriculturally and clinically important Fusarium species, including the F. solani species complex (FSSC). Subsequently, this concept was challenged in 2015 by one research group who proposed dividing the genus Fusarium into seven genera, including the FSSC described as members of the genus Neocosmospora, with subsequent justification in 2018 based on claims that the 2013 concept of Fusarium is polyphyletic. Here, we test this claim and provide a phylogeny based on exonic nucleotide sequences of 19 orthologous protein-coding genes that strongly support the monophyly of Fusarium including the FSSC. We reassert the practical and scientific argument in support of a genus Fusarium that includes the FSSC and several other basal lineages, consistent with the longstanding use of this name among plant pathologists, medical mycologists, quarantine officials, regulatory agencies, students, and researchers with a stake in its taxonomy. In recognition of this monophyly, 40 species described as genus Neocosmospora were recombined in genus Fusarium, and nine others were renamed Fusarium. Here the global Fusarium community voices strong support for the inclusion of the FSSC in Fusarium, as it remains the best scientific, nomenclatural, and practical taxonomic option available.

Adaptation to different types of environmental stress is a common part of life for today's fungi. A deeper understanding of the organization, regulation and evolution of fungal stress response systems may lead to the development of novel antifungal drugs and technologies or the engineering of industrial strains with elevated stress tolerance. Here we present the Fungal Stress Response Database (http://internal.med.unideb.hu/fsrd) aimed to stimulate further research on stress biology of fungi. The database incorporates 1985 fungal stress response proteins with verified physiological function(s) and their orthologs identified and annotated in 28 species including human and plant pathogens, as well as important industrial fungi. The database will be extended continuously to cover other fully sequenced fungal species. Our database, as a starting point for future stress research, facilitates the analysis of literature data on stress and the identification of ortholog groups of stress response proteins in newly sequenced fungal genomes. [ABSTRACT FROM AUTHOR]

We report the isolation and expression profiles of a single-copy gene from the mycoparasitic fungus Trichoderma hamatum encoding a 60 S cytoplasmic ribosomal protein. The gene, named RPL36, was cloned through its nutrient-mediated expression, using mRNA differential screening. Its predicted ORF, interrupted by two introns, encoded a 105-aa polypeptide. The deduced rpL36 protein showed high overall homologies with other L36-type ribosomal proteins isolated from yeast, rat and human. Analysis of the promoter region of RPL36 revealed the presence of two ribosomal protein gene (RPG) boxes and a T-rich region known to be involved in the regulation of most ribosomal protein genes. Expression of RPL36 was tightly regulated by carbon and nitrogen availability. The mRNA levels of this gene decreased upon exposure of the mycelium to different stresses, whereas the addition of cycloheximide resulted in a super-induction. Levels of RPL36 transcripts also increased during mycoparasitic interaction between T. hamatum and Botrytis cinerea. [ABSTRACT FROM AUTHOR]

Adaptation to different types of environmental stress is a common part of life for today's fungi. A deeper understanding of the organization, regulation and evolution of fungal stress response systems may lead to the development of novel antifungal drugs and technologies or the engineering of industrial strains with elevated stress tolerance. Here we present the Fungal Stress Response Database (http://internal.med.unideb.hu/fsrd) aimed to stimulate further research on stress biology of fungi. The database incorporates 1985 fungal stress response proteins with verified physiological function(s) and their orthologs identified and annotated in 28 species including human and plant pathogens, as well as important industrial fungi. The database will be extended continuously to cover other fully sequenced fungal species. Our database, as a starting point for future stress research, facilitates the analysis of literature data on stress and the identification of ortholog groups of stress response proteins in newly sequenced fungal genomes. Database URL: http://internal.med.unideb.hu/fsrd

Fpmtr1, an amino acid transporter gene from Fusarium proliferatum was strongly expressed during conidial germination and repressed in late stationary phase. To identify the specific function of this gene, DeltaFpmtr1 knock-out mutants were generated by gene replacement. Vegetative growth of the DeltaFpmtr1 mutants was normal both in liquid and on solid media, but conidial germination was delayed. The DeltaFpmtr1 mutants and the wild type were equally fertile when used as males in sexual crosses, however if the mutants were used as the female parent then the fertility of the cross decreased dramatically. Inactivation of Fpmtr1 abolished vegetative self-incompatibility in strain ITEM 2287 of F. proliferatum, but the DeltaFpmtr1 mutants were still vegetatively incompatible with the other strains of the fungus. Endophytic colonization capability of the mutants, assessed on maize seedlings also was adversely affected. These data suggest that Fpmtr1 is involved in multiple developmental processes related to both sexual and parasexual events in F. proliferatum. Furthermore, the fungus might have problems in adapting to a less than optimal environment if this otherwise dispensable transporter has been inactivated.

Thermobifida fusca TM51, a thermophilic actinomycete isolated from composted horse manure, was found to produce a number of lignocellulose-degrading hydrolases, including endoglucanases, exoglucanases, endoxylanases, beta-xylosidases, endomannanases, and beta-mannosidases, when grown on cellulose or hemicellulose as carbon sources. beta-Mannosidases (EC 3.2.1.25), although contributing to the hydrolysis of hemicellulose fractions, such as galacto-mannans, constitute a lesser-known group of the lytic enzyme systems due to their low representation in the proteins secreted by hemicellulolytic microorganisms. An expression library of T. fusca, prepared in Streptomyces lividans TK24, was screened for beta-mannosidase activity to clone genes coding for mannosidases. One positive clone was identified, and a beta-mannosidase-encoding gene (manB) was isolated. Sequence analysis of the deduced amino acid sequence of the putative ManB protein revealed substantial similarity to known mannosidases in family 2 of the glycosyl hydrolase enzymes. The calculated molecular mass of the predicted protein was 94 kDa, with an estimated pI of 4.87. S. lividans was used as heterologous expression host for the putative beta-mannosidase gene of T. fusca. The purified gene product obtained from the culture filtrate of S. lividans was then subjected to more-detailed biochemical analysis. Temperature and pH optima of the recombinant enzyme were 53 degrees C and 7.17, respectively. Substrate specificity tests revealed that the enzyme exerts only beta-D-mannosidase activity. Its kinetic parameters, determined on para-nitrophenyl beta-D-mannopyranoside (pNP-betaM) substrate were as follows: K(m) = 180 micro M and V(max) = 5.96 micro mol min(-1) mg(-1); the inhibition constant for mannose was K(i) = 5.5 mM. Glucono-lacton had no effect on the enzyme activity. A moderate trans-glycosidase activity was also observed when the enzyme was incubated in the presence of pNP-alphaM and pNP-betaM; under these conditions mannosyl groups were transferred by the enzyme from pNP-betaM to pNP-alphaM resulting in the synthesis of small amounts (1 to 2%) of disaccharides.