Publications by authors named "Ivo Zadra"

The fungal velvet complex is a light-dependent master regulator of secondary metabolism and development in the major penicillin producer, Penicillium chrysogenum. However, the light-dependent mechanism is unclear. To identify velvet-dependent transcriptional regulators that show light-regulated expression, we performed microarray hybridizations with RNA isolated from P.

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The filamentous fungus Acremonium chrysogenum is the industrial producer of the β-lactam antibiotic cephalosporin C. Here, we present the genome sequence of strain ATCC 11550, which contains genes for 8,901 proteins, 127 tRNAs, and 22 rRNAs. Genome annotation led to the prediction of 42 gene clusters for secondary metabolites.

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Penicillium chrysogenum is the major industrial producer of the β-lactam antibiotic penicillin. Here, we report the complete genome sequence of the industrial progenitor strain P. chrysogenum P2niaD18 in a chromosome-scale genome assembly.

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Penicillium chrysogenum is a filamentous fungus of major medical and historical importance, being the original and present-day industrial source of the antibiotic penicillin. The species has been considered asexual for more than 100 y, and despite concerted efforts, it has not been possible to induce sexual reproduction, which has prevented sexual crosses being used for strain improvement. However, using knowledge of mating-type (MAT) gene organization, we now describe conditions under which a sexual cycle can be induced leading to production of meiotic ascospores.

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Penicillin production in Penicillium chrysogenum is controlled by PcVelA and PcLaeA, two components of the regulatory velvet-like complex. Comparative microarray analysis with mutants lacking PcVelA or PcLaeA revealed a set of 62 common genes affected by the loss of both components. A downregulated gene in both knockout strains is PcchiB1, potentially encoding a class V chitinase.

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Article Synopsis
  • Penicillium chrysogenum produces a protein called PAF, which inhibits the growth of various fungi, especially Aspergillus nidulans, but has little effect on itself.
  • This study reveals that PAF does more than just fight off other fungi; it also promotes conidiation (spore formation) in P. chrysogenum by influencing the expression of a key regulatory gene, brlA.
  • A strain of P. chrysogenum lacking PAF showed significantly reduced spore formation, suggesting that PAF is crucial for normal asexual reproduction in this fungus.
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In filamentous fungi, secondary metabolism is often linked with developmental processes such as conidiation. In this study we analyzed the link between secondary metabolism and conidiation in the main industrial producer of the β-lactam antibiotic penicillin, the ascomycete Penicillium chrysogenum. Therefore, we generated mutants defective in two central regulators of conidiation, the transcription factors BrlA and StuA.

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Genetic engineering requires genetic selection markers. For generation of biosafe strains in industrial applications, homologous dominant selection markers allowing "self-cloning" are best suited but scarce. Here we describe a novel homologous dominant genetic selection system for the filamentous fungus Penicillium chrysogenum based on overexpression of the P.

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Penicillium chrysogenum is the industrial producer of the antibiotic penicillin, whose biosynthetic regulation is barely understood. Here, we provide a functional analysis of two major homologues of the velvet complex in P. chrysogenum, which we have named P.

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In Penicillium chrysogenum, the industrial producer of the beta-lactam antibiotic penicillin, generating gene replacements for functional analyses is very inefficient. Here, we constructed a recipient strain that allows efficient disruption of any target gene via homologous recombination. Following isolation of the Pcku70 (syn.

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The Penicillium chrysogenumantifungal protein PAF is secreted into the supernatant after elimination of a preprosequence. PAF is actively internalized into the hyphae of sensitive molds and provokes growth retardation as well as changes in morphology. Thus far, no information is available on the exact mode of action of PAF, nor on the function of its prosequence in protein activity.

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The filamentous ascomycete A. nidulans produces two major siderophores: it excretes triacetylfusarinine C to capture iron and contains ferricrocin intracellularly. In this study we report the characterization of two siderophore biosynthetic genes, sidA encoding l-ornithine N(5)-monooxygenase and sidC encoding a non-ribosomal peptide synthetase respectively.

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In the filamentous fungus Aspergillus nidulans, iron homeostasis is regulated at the transcriptional level by the negative-acting GATA factor SREA. In this study the expression of a putative heme-containing metalloreductase-encoding gene, freA, was found to be upregulated by iron limitation independently of SREA, demonstrating the existence of an iron-regulatory mechanism which does not involve SREA. In contrast to freA, various other genes encoding proteins in need of iron-containing cofactors-acoA, lysF, and cycA-were downregulated in response to iron depletion.

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