We investigated the functions of the highly expressed, sporulation-specific SpoC1 genes of Aspergillus nidulans by deleting the entire 38-kb SpoC1 gene cluster. The resultant mutant strain did not differ from the wild type in (1) growth rate, (2) morphology of specialized reproductive structures formed during completion of the asexual or sexual life cycles, (3) sporulation efficiency, (4) spore...

We describe the cloning and characterization of the gene coding for the ribotoxin restrictocin, from Aspergillus restrictus (gene res, EMBL accession Number X56176). This toxin is a potent inhibitor of protein synthesis in eucaryotes and is of potential interest as a component of immunotoxins. To analyze the mechanism of self-protection in the producing organism, the res gene was cloned into th...

Light regulates several aspects of the biology of many organisms, including the balance between asexual and sexual development in some fungi. To understand how light regulates fungal development at the molecular level we have used Aspergillus nidulans as a model. We have performed a genome-wide expression analysis that has allowed us to identify >400 genes upregulated and >100 genes downregulat...

Two Aspergillus nidulans genes, xlnA and xlnB, encoding the X22 and X24 xylanases from this fungus, respectively, have been cloned and sequenced. Their cDNAs have been expressed in a laboratory Saccharomyces cerevisiae strain under the control of a constitutive yeast promoter, resulting in the construction of recombinant xylanolytic yeast strains.

We systematically investigated the efficiency of Aspergillus nidulans transformation using protoplasts prepared from different stages of conidiospore germination and young mycelium. Using standard integrative plasmids, increased transformation yields were obtained with protoplasts isolated from a specific stage coincident with germ tube emergence. This increase ranged, on the average, from two-...

We have studied compensatory evolution in a fludioxonil resistant mutant of the filamentous fungus Aspergillus nidulans. In an evolution experiment lasting for 27 weeks (about 3000 cell cycles) 35 parallel strains of this mutant evolved in three different environmental conditions. Our results show a severe cost of resistance (56%) in the absence of fludioxonil and in all conditions the mutant s...

This study describes two novel regulators, GalX and GalR, that control d-galactose utilization in Aspergillus nidulans. This system is unique for A. nidulans since no GalR homologs were found in other ascomycetes. GalR shares significant sequence identity with the arabinanolytic and xylanolytic regulators AraR and XlnR, but GalX is more distantly related.

The niaD gene of the fungus Aspergillus nidulans encodes an assimilatory nitrate reductase and exogenous ammonium represses its expression. Under anoxic conditions, however, A. nidulans expressed niaD even in the presence of ammonium and used the gene product for dissimilatory nitrate reduction (ammonia fermentation). This transcription regulation mechanism under anaerobiosis is critical for th...

We developed a PCR-based assay to differentiate medically important species of Aspergillus from one another and from other opportunistic molds and yeasts by employing universal, fungus-specific primers and DNA probes in an enzyme immunoassay format (PCR-EIA). Oligonucleotide probes, directed to the internal transcribed spacer 2 region of ribosomal DNA from Aspergillus flavus, Aspergillus fumiga...