The Cultivation Method Affects the Transcriptomic Response of Aspergillus niger to Growth on Sugar Beet Pulp.

In nature, filamentous fungi are exposed to diverse nutritional sources and changes in substrate availability. Conversely, in submerged cultures, mycelia are continuously exposed to the existing substrates, which are depleted over time. Submerged cultures are the preferred choice for experimental setups in laboratory and industry and are often used for understanding the physiology of fungi.

Identification of a Novel Biosynthetic Gene Cluster in Using Comparative Genomics.

Previously, DNA microarrays analysis showed that, in co-culture with , a biosynthetic gene cluster anchored with a nonribosomal peptides synthetase of is downregulated. Based on phylogenetic and synteny analyses, we show here that this gene cluster, , comprises genes predicted to encode a nonribosomal peptides synthetase, a FAD-binding domain-containing protein, an uncharacterized protein, a transporter, a cytochrome P450 protein, a NAD(P)-binding domain-containing protein and a transcription factor. We overexpressed the in-cluster transcription factor gene .

The Canadian Fungal Research Network: current challenges and future opportunities.

Fungi critically impact the health and function of global ecosystems and economies. In Canada, fungal researchers often work within silos defined by subdiscipline and institutional type, complicating the collaborations necessary to understand the impacts fungi have on the environment, economy, and plant and animal health. Here, we announce the establishment of the Canadian Fungal Research Network (CanFunNet, https://fungalresearch.

The presence of trace components significantly broadens the molecular response of Aspergillus niger to guar gum.

Guar gum consists mainly of galactomannan and constitutes the endosperm of guar seeds that acts as a reserve polysaccharide for germination. Due to its molecular structure and physical properties, this biopolymer has been considered as one of the most important and widely used gums in industry. However, for many of these applications this (hemi-)cellulosic structure needs to be modified or (partially) depolymerized in order to customize and improve its physicochemical properties.

Evolutionary Adaptation to Generate Mutants.

In this chapter we describe a method to generate mutants of filamentous fungi using their genomic plasticity and rapid adaptability to their environment. This method is based on spontaneous mutations occurring in relation to improved growth of fungi on media by repeated inoculation resulting in adaptation of the strain to the condition. The critical aspect of this method is the design of the selective media, which will depend strongly on the phenomenon that will be studied.

Expression-based clustering of CAZyme-encoding genes of Aspergillus niger.

Background: The Aspergillus niger genome contains a large repertoire of genes encoding carbohydrate active enzymes (CAZymes) that are targeted to plant polysaccharide degradation enabling A. niger to grow on a wide range of plant biomass substrates. Which genes need to be activated in certain environmental conditions depends on the composition of the available substrate.

Diversity of fungal feruloyl esterases: updated phylogenetic classification, properties, and industrial applications.

Feruloyl esterases (FAEs) represent a diverse group of carboxyl esterases that specifically catalyze the hydrolysis of ester bonds between ferulic (hydroxycinnamic) acid and plant cell wall polysaccharides. Therefore, FAEs act as accessory enzymes to assist xylanolytic and pectinolytic enzymes in gaining access to their site of action during biomass conversion. Their ability to release ferulic acid and other hydroxycinnamic acids from plant biomass makes FAEs potential biocatalysts in a wide variety of applications such as in biofuel, food and feed, pulp and paper, cosmetics, and pharmaceutical industries.

Secretion of small proteins is species-specific within Aspergillus sp.

Small secreted proteins (SSP) have been defined as proteins containing a signal peptide and a sequence of less than 300 amino acids. In this analysis, we have compared the secretion pattern of SSPs among eight aspergilli species in the context of plant biomass degradation and have highlighted putative interesting candidates that could be involved in the degradative process or in the strategies developed by fungi to resist the associated stress that could be due to the toxicity of some aromatic compounds or reactive oxygen species released during degradation. Among these candidates, for example, some stress-related superoxide dismutases or some hydrophobic surface binding proteins (HsbA) are specifically secreted according to the species .

Improving cellulase production by Aspergillus niger using adaptive evolution.

Objectives: To evaluate the potential of adaptive evolution as a tool in generating strains with an improved production of plant biomass degrading enzymes.

Results: An Aspergillus niger cellulase mutant was obtained by adaptive evolution. Physiological properties of this mutant revealed a five times higher cellulose production than the parental strain.