CRISPR/Cas9 technology enables the development of the filamentous ascomycete fungus Penicillium subrubescens as a new industrial enzyme producer

The filamentous ascomycete Aspergillus awamori secretes large amounts of glucoamylase upon growth in medium containing starch, glucose, or a variety of hexose sugars and sugar polymers. We examined the mechanism of this carbon source-dependent regulation of glucoamylase accumulation and found a several hundredfold increase in glucoamylase mRNA in cells grown on an inducing substrate, starch, relative to cells grown on a noninducing substrate, xylose. We postulate that induction of glucoamylase synthesis is regulated transcriptionally. Comparing total mRNA from cells grown on starch and xylose, we were able to identify an inducible 2.3-kilobase mRNA-encoding glucoamylase. The glucoamylase mRNA was purified and used to identify a molecularly cloned 3.4-kilobase EcoRI fragment containing the A. awamori glucoamylase gene. Comparison of the nucleotide sequence of the 3.4-kilobase EcoRI fragment with that of the glucoamylase I mRNA (as determined from molecularly cloned cDNA) revealed the existence of four intervening sequences within the glucoamylase gene. The 5' end of the glucoamylase mRNA was mapped to several locations within a region -52 to -73 nucleotides from the translational start. Sequence and structural features of the glucoamylase gene of the filamentous ascomycete A. awamori were examined and compared with those reported in genes of other eucaryotes.

Download Full-text

Filamentous ascomycete and basidiomycete fungi from beach sand

RENDICONTI LINCEI ◽

10.1007/s12210-016-0535-5 ◽

2016 ◽

Vol 27 (4) ◽

pp. 603-607 ◽

Cited By ~ 3

Author(s):

Teh Li Yee ◽

Rosnida Tajuddin ◽

Nik Mohd Izham Mohamed Nor ◽

Masratul Hawa Mohd ◽

Latiffah Zakaria

Keyword(s):

Beach Sand ◽

Filamentous Ascomycete ◽

Basidiomycete Fungi

Download Full-text

Unique Patterns of Mating Pheromone Presence and Absence could Result in the Ambiguous Sexual Behaviours of Colletotrichum Species

10.21203/rs.3.rs-112807/v1 ◽

2020 ◽

Author(s):

Andrea Melissa Wilson ◽

RV Lelwala ◽

PWJ Taylor ◽

MJ Wingfield ◽

BD WINGFIELD

Keyword(s):

Mating Type ◽

Molecular Mechanisms ◽

Mating Strategies ◽

Mating Partner ◽

Filamentous Ascomycete ◽

Sexual Behaviours ◽

History Of ◽

Ascomycete Fungi ◽

Presence And Absence ◽

Sexual Progeny

Abstract Background: Colletotrichum species are known to engage in unique sexual behaviours that differ significantly from the mating strategies of other filamentous ascomycete species. Most ascomycete fungi require the expression of both the MAT1-1-1 and MAT1-2-1 genes to regulate mating type and induce sexual reproduction. In contrast, all isolates of Colletotrichum are known to harbour only the MAT1-2-1 gene and yet, are capable of recognizing suitable mating partners and producing sexual progeny. The molecular mechanisms contributing to mating types and behaviours in Colletotrichum are thus unknown. Results: A comparative genomics approach analysing genomes from 47 Colletotrichum isolates was used to elucidate a putative molecular mechanism underlying the unique sexual behaviours observed in Colletotrichum species. The existence of only the MAT1-2 idiomorph was confirmed across all species included in this study. Comparisons at the loci harbouring the two mating pheromones and their cognate receptors revealed interesting patterns of gene presence and absence as well as gene loss. The results also showed that these genes have been lost multiple times over the evolutionary history of this genus. Conclusion: The multiple losses of the pheromone genes in these species suggest strong selection against the typical mating strategies seen in other species. This further suggests that these pheromones no longer play a role in mating type determination and that the species of this genus have undiscovered mechanisms by which to control mating type and mating partner recognition. This research thus provides a base from which further interrogation of this topic can take place.

Download Full-text

Secretion of Cryparin, a Fungal Hydrophobin

Applied and Environmental Microbiology ◽

10.1128/aem.65.12.5431-5435.1999 ◽

1999 ◽

Vol 65 (12) ◽

pp. 5431-5435 ◽

Cited By ~ 15

Author(s):

Patricia M. McCabe ◽

Neal K. Van Alfen

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Submerged Culture ◽

Secretory Pathway ◽

Culture Medium ◽

Secretory Vesicle ◽

Cryphonectria Parasitica ◽

Secreted Protein ◽

Filamentous Ascomycete ◽

A Cell

ABSTRACT Cryparin is a cell-surface-associated hydrophobin of the filamentous ascomycete Cryphonectria parasitica. This protein contains a signal peptide that directs it to the vesicle-mediated secretory pathway. We detected a glycosylated form of cryparin in a secretory vesicle fraction, but secreted forms of this protein are not glycosylated. This glycosylation occurred in the proprotein region, which is cleaved during maturation by a Kex2-like serine protease, leaving a mature form of cryparin that could be isolated from both the cell wall and culture medium. Pulse-chase labeling experiments showed that cryparin was secreted through the cell wall, without being bound, into the culture medium. The secreted protein then binds to the cell walls ofC. parasitica, where it remains. Binding of cryparin to the cell wall occurred in submerged culture, presumably because of the lectin-like properties unique to this hydrophobin. Thus, the binding of this hydrophobin to the cell wall is different from that of other hydrophobins which are reported to require a hydrophobic-hydrophilic interface for assembly.

Download Full-text