Transcriptional upregulation of four genes of the lysine biosynthetic pathway by homocitrate accumulation in Penicillium chrysogenum: homocitrate as a sensor of lysine-pathway distress
| Autor: | Ricardo V. Ullán, Leopoldo Naranjo, Carlos García-Estrada, José-Martín Scervino, Juan F. Martín, Tania Velasco-Conde, Mónica Lamas-Maceiras, Javier Casqueiro, Franco Teves, Xiaobin Wu |
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| Rok vydání: | 2009 |
| Předmět: |
Auxotrophy
Genes Fungal Molecular Sequence Data Lysine Mutant Penicillium chrysogenum Homocitrate synthase Models Biological Microbiology Fungal Proteins purl.org/becyt/ford/1 [https] chemistry.chemical_compound Transformation Genetic Biosynthesis Aspergillus nidulans Point Mutation Penicilin Amino Acid Sequence RNA Messenger Cloning Molecular DNA Fungal purl.org/becyt/ford/1.6 [https] Hydro-Lyases DNA Primers Sequence Homology Amino Acid biology Genetic Complementation Test Fungal genetics Tricarboxylic Acids RNA Fungal biology.organism_classification Up-Regulation Amino Acid Substitution chemistry Biochemistry biology.protein |
| Zdroj: | CONICET Digital (CONICET) Consejo Nacional de Investigaciones Científicas y Técnicas instacron:CONICET |
| ISSN: | 1465-2080 1350-0872 |
| DOI: | 10.1099/mic.0.031005-0 |
| Popis: | The lysine biosynthetic pathway has to supply large amounts of α-aminoadipic acid for penicillin biosynthesis in Penicillium chrysogenum. In this study, we have characterized the P. chrysogenum L2 mutant, a lysine auxotroph that shows highly increased expression of several lysine biosynthesis genes (lys1, lys2, lys3, lys7). The L2 mutant was found to be deficient in homoaconitase activity since it was complemented by the Aspergillus nidulans lysF gene. We have cloned a gene (named lys3) that complements the L2 mutation by transformation with a P. chrysogenum genomic library, constructed in an autonomous replicating plasmid. The lys3-encoded protein showed high identity to homoaconitases. In addition, we cloned the mutant lys3 allele from the L2 strain that showed a G1534 to A1534 point mutation resulting in a Gly495 to Asp495 substitution. This mutation is located in a highly conserved region adjacent to two of the three cysteine residues that act as ligands to bind the iron-sulfur cluster required for homoaconitase activity. The L2 mutant accumulates homocitrate. Deletion of the lys1 gene (homocitrate synthase) in the L2 strain prevented homocitrate accumulation and reverted expression levels of the four lysine biosynthesis genes tested to those of the parental prototrophic strain. Homocitrate accumulation seems to act as a sensor of lysine-pathway distress, triggering overexpression of four of the lysine biosynthesis genes. Fil: Teves, Franco. Universidad de León; España Fil: Lamas Maceiras, Mónica. Universidad de León; España Fil: García Estrada, Carlos. Instituto de Biotecnología de León; España Fil: Casqueiro, Javier. Instituto de Biotecnología de León; España. Universidad de León; España Fil: Naranjo, Leopoldo. Universidad de León; España Fil: Ullán, Ricardo V.. Instituto de Biotecnología de León; España Fil: Scervino, Jose Martin. Instituto de Biotecnología de León; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Wu, Xiaobin. Instituto de Biotecnología de León; España Fil: Velasco Conde, Tania. Instituto de Biotecnología de León; España Fil: Martín, Juan F.. Instituto de Biotecnología de León; España. Universidad de León; España |
| Databáze: | OpenAIRE |
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