Generation, Transfer, and Loss of Alternative Oxidase Paralogues in the Family.

Alternative oxidase (Aox) is a terminal oxidase operating in branched electron transport. The activity correlates positively with overflow metabolisms in certain , converting intracellular glucose by the shortest possible path into organic acids, like citrate or itaconate. Aox is nearly ubiquitous in fungi, but gene multiplicity is rare.

Manganese(II) ions suppress the transcription of the citrate exporter encoding gene in .

is an important filamentous fungus used for the industrial production of citric acid. One of the most important factors that affect citric acid production is the concentration of manganese(II) ions present in the culture broth. Under manganese(II)-limiting conditions, the fungus develops a pellet-like morphology that is crucial for high citric acid accumulation.

Hybrid Cultivars with American or Asian Ancestries Show Higher Tolerance towards Grapevine Trunk Diseases.

Grape production worldwide is increasingly threatened by grapevine trunk diseases (GTDs). No grapevine cultivar is known to be entirely resistant to GTDs, but susceptibility varies greatly. To quantify these differences, four Hungarian grape germplasm collections containing 305 different cultivars were surveyed to determine the ratios of GTDs based on symptom expression and the proportion of plant loss within all GTD symptoms.

The Biocontrol Potential of Endophytic Fungi Isolated from Hungarian Grapevines, Part II, Grapevine Stimulation.

In the first part of this two-piece publication, the isolation, identification and in vitro characterization of ten endophytic isolates were reported. Here we report the ability of two different mixes of some of these isolates ( and as well as of and ) to colonize and stimulate the growth of grapevines. Two commercial vineyards about 400 km away from the site of isolation were used as experimental fields, from which the strains of three species were re-isolated up to four years after rootstock soaking treatment with conidiospores, performed before planting.

Type Strains of Entomopathogenic Nematode-Symbiotic Bacterium Species, (EMC) and (EMA), Are Exceptional Sources of Non-Ribosomal Templated, Large-Target-Spectral, Thermotolerant-Antimicrobial Peptides (by Both), and Iodinin (by EMC).

Antimicrobial multidrug resistance (MDR) is a global challenge, not only for public health, but also for sustainable agriculture. Antibiotics used in humans should be ruled out for use in veterinary or agricultural settings. Applying antimicrobial peptide (AMP) molecules, produced by soil-born organisms for protecting (soil-born) plants, seems a preferable alternative.

GalR, GalX and AraR co-regulate d-galactose and l-arabinose utilization in Aspergillus nidulans.

Filamentous fungi produce a wide variety of enzymes in order to efficiently degrade plant cell wall polysaccharides. The production of these enzymes is controlled by transcriptional regulators, which also control the catabolic pathways that convert the released monosaccharides. Two transcriptional regulators, GalX and GalR, control d-galactose utilization in the model filamentous fungus Aspergillus nidulans, while the arabinanolytic regulator AraR regulates l-arabinose catabolism.

The Biocontrol Potential of Endophytic Fungi Isolated from Hungarian Grapevines. Part I. Isolation, Identification and In Vitro Studies.

This paper reports on the identification and in vitro characterization of several strains isolated from the Tokaj Wine Region in North-East Hungary. Ten isolates were analyzed and found to consist of six individual species-, , , , and  . The growth potential of the strains was assessed at a range of temperatures.

Internally Symmetrical Stwintrons and Related Canonical Introns in Hypoxylaceae Species.

Spliceosomal introns are pervasive in eukaryotes. Intron gains and losses have occurred throughout evolution, but the origin of new introns is unclear. Stwintrons are complex intervening sequences where one of the sequence elements (5'-donor, lariat branch point element or 3'-acceptor) necessary for excision of a U2 intron (external intron) is itself interrupted by a second (internal) U2 intron.

The Role of Metal Ions in Fungal Organic Acid Accumulation.

Organic acid accumulation is probably the best-known example of primary metabolic overflow. Both bacteria and fungi are capable of producing various organic acids in large amounts under certain conditions, but in terms of productivity-and consequently, of commercial importance-fungal platforms are unparalleled. For high product yield, chemical composition of the growth medium is crucial in providing the necessary conditions, of which the concentrations of four of the first-row transition metal elements, manganese (Mn), iron (Fe), copper (Cu) and zinc (Zn) stand out.

Complex intron generation in the yeast genus Lipomyces.

In primary transcripts of eukaryotic nuclear genes, coding sequences are often interrupted by U2-type introns. Such intervening sequences can constitute complex introns excised by consecutive splicing reactions. The origin of spliceosomal introns is a vexing problem.

The effects of external Mn concentration on hyphal morphology and citric acid production are mediated primarily by the NRAMP-family transporter DmtA in Aspergillus niger.

Background: Citric acid, a commodity product of industrial biotechnology, is produced by fermentation of the filamentous fungus Aspergillus niger. A requirement for high-yield citric acid production is keeping the concentration of Mn ions in the medium at or below 5 µg L. Understanding manganese metabolism in A.

Manganese Deficiency Is Required for High Itaconic Acid Production From D-Xylose in .

Itaconic acid is used as a bio-based, renewable building block in the polymer industry. It is produced by submerged fermentations of the filamentous fungus from molasses or starch, but research over the efficient utilization of non-food, lignocellulosic plant biomass is soaring. The objective of this study was to test whether the application of two key cultivation parameters for obtaining itaconic acid from D-glucose in high yields - Mn ion deficiency and high concentration of the carbon source - would also occur on D-xylose, the principal monomer of lignocellulose.

A spliceosomal twin intron (stwintron) participates in both exon skipping and evolutionary exon loss.

Spliceosomal twin introns (stwintrons) are introns where any of the three consensus sequences involved in splicing is interrupted by another intron (internal intron). In Aspergillus nidulans, a donor-disrupted stwintron (intron-1) is extant in the transcript encoding a reticulon-like protein. The orthologous transcript of Aspergillus niger can be alternatively spliced; the exon downstream the stwintron could be skipped by excising a sequence that comprises this stwintron, the neighbouring intron-2, and the exon bounded by these.

Citric acid and itaconic acid accumulation: variations of the same story?

Citric acid production by Aspergillus niger and itaconic acid production by Aspergillus terreus are two major examples of technical scale fungal fermentations based on metabolic overflow of primary metabolism. Both organic acids are formed by the same metabolic pathway, but whereas citric acid is the end product in A. niger, A.

High oxygen tension increases itaconic acid accumulation, glucose consumption, and the expression and activity of alternative oxidase in Aspergillus terreus.

Itaconic acid is a five-carbon dicarboxylic acid with an unsaturated alkene bond, frequently used as a building block for the industrial production of a variety of synthetic polymers. It is also one of the major products of fungal "overflow metabolism" which can be produced in submerged fermentations of the filamentous fungus Aspergillus terreus. At the present, molar yields of itaconate are lower than those obtained in citric acid production in Aspergillus niger.

Analysis of the Relationship between Alternative Respiration and Sterigmatocystin Formation in .

has one gene for alternative oxidase (EC 1.10.3.

Emergence and loss of spliceosomal twin introns.

Background: In the primary transcript of nuclear genes, coding sequences-exons-usually alternate with non-coding sequences-introns. In the evolution of spliceosomal intron-exon structure, extant intron positions can be abandoned and new intron positions can be occupied. Spliceosomal twin introns ("stwintrons") are unconventional intervening sequences where a standard "internal" intron interrupts a canonical splicing motif of a second, "external" intron.

Identification of a mutarotase gene involved in D-galactose utilization in Aspergillus nidulans.

Aldose 1-epimerases or mutarotases (EC 5.1.3.

A mechanism for a single nucleotide intron shift.

Spliceosomal introns can occupy nearby rather than identical positions in orthologous genes (intron sliding or shifting). Stwintrons are complex intervening sequences, where an 'internal' intron interrupts one of the sequences essential for splicing, generating after its excision, a newly formed canonical intron defined as 'external'. In one experimentally demonstrated configuration, two alternatively excised internal introns, overlapping by one G, disrupt respectively the donor and the acceptor sequence of an external intron, leading to mRNAs encoding identical proteins.