Publications

• An evolutionary conserved d-galacturonic acid metabolic pathway operates across filamentous fungi capable of pectin degradation.

  Martens-Uzunova E.S., Schaap P.J.

  Transcriptome analysis of Aspergillus niger transfer cultures grown on galacturonic acid media identified a highly correlating cluster of four strongly induced hypothetical genes linked with a subset set of genes encoding pectin degrading enzymes. Three of the encoded hypothetical proteins now des ... >> More

  Transcriptome analysis of Aspergillus niger transfer cultures grown on galacturonic acid media identified a highly correlating cluster of four strongly induced hypothetical genes linked with a subset set of genes encoding pectin degrading enzymes. Three of the encoded hypothetical proteins now designated GAAA to GAAC are directly involved in further galacturonic acid catabolism. Functional and biochemical analysis revealed that GAAA is a novel d-galacturonic acid reductase. Two non-allelic Aspergillus nidulans strains unable to utilize galacturonic acid are mutated in orthologs of gaaA and gaaB, respectively. The A. niger gaaA and gaaC genes share a common promoter region. This feature appears to be strictly conserved in the genomes of plant cell wall degrading fungi from subphylum Pezizomycotina. Combined with the presence of homologs of the gaaB gene in the same set of fungi, these strongly suggest that a common d-galacturonic acid utilization pathway is operative in these species. << Less

  Fungal Genet. Biol. 45:1449-1457(2008) [PubMed] [EuropePMC]

  This publication is cited by 2 other entries.

• L-galactonate dehydratase is part of the fungal path for D-galacturonic acid catabolism.

  Kuorelahti S., Jouhten P., Maaheimo H., Penttila M., Richard P.

  An L-galactonate dehydratase and the corresponding gene were identified from the mould Hypocrea jecorina (Trichoderma reesei). This novel enzyme converts L-galactonate to L-threo-3-deoxy-hexulosonate (2-keto-3-deoxy-L-galactonate). The enzyme is part of the fungal pathway for D-galacturonic acid c ... >> More

  An L-galactonate dehydratase and the corresponding gene were identified from the mould Hypocrea jecorina (Trichoderma reesei). This novel enzyme converts L-galactonate to L-threo-3-deoxy-hexulosonate (2-keto-3-deoxy-L-galactonate). The enzyme is part of the fungal pathway for D-galacturonic acid catabolism, a pathway which is only partly known. It is the second enzyme of this pathway after the D-galacturonic acid reductase. L-galactonate dehydratase activity is present in H. jecorina cells grown on D-galacturonic acid but absent when other carbon sources are used for growth. A deletion of the L-galactonate dehydratase gene in H. jecorina results in a strain with no growth on D-galacturonic acid. The active enzyme was produced in the heterologous host Saccharomyces cerevisiae and characterized. It exhibited activity with L-galactonate and D-arabonate where the hydroxyl group of the C2 is in L- and the hydroxyl group of the C3 is in D-configuration in the Fischer projection. However, it did not exhibit activity with D-galactonate, D-gluconate, L-gulonate or D-xylonate where the hydroxyl groups of the C2 and C3 are in different configuration. << Less

  Mol. Microbiol. 61:1060-1068(2006) [PubMed] [EuropePMC]