Project description:The brown rot fungus, Fomitopsis pinicola strain FP-58527, was cultivated in media containing ground Populus tremuloides, Pinus taeda or Picea glauca wood as sole carbon source. Mass spectrometry analyses identified proteins likely involved in the degradation of lignocellulose. Patterns of enzymes detected varied with substrate.
Project description:The brown rot fungus, Fomitopsis pinicola strain FP-58527, was cultivated in media containing ground Populus tremuloides, Pinus taeda or Picea glauca wood as sole carbon source. Mass spectrometry analyses identified proteins likely involved in the degradation of lignocellulose. Patterns of enzymes detected varied with substrate.
Project description:The brown rot wood decay fungus, Fomitopsis pinicola strain FP-58527, was cultivated for five dayes in media containing ground Populus tremuloides, Pinus taeda or Picea glauca wood as sole carbon source. Extracellular proteomic component was extracted and analyzed by LC-MS/MS.
Project description:Brown rot fungi play an essential role in carbon cycling by decomposing lignocellulose into substrates usable by themselves and other microbes. Interactions between bacteria and fungi can be competitive or beneficial, but these relationships are not well understood because of a lack of good model systems. To model cross-feeding between fungi and bacteria, wood decayed by the brown rot fungus Rhodonia placenta was used as a carbon source for the phototrophic bacterium Rhodopseudomonas palustris. We found that fungal decay products generated by Rda. placenta could be used by R. palustris for growth, and later decay stages contained more usable substrates than early stages. Mass spectrometry identified a range of aromatic and non-aromatic acids, but after 95 days of bacterial growth, R. palustris only consumed non-aromatic acids over the aromatic lignin monomers. Genes involved with aromatic compound degradation were unimportant for growth and RNA sequencing revealed that aromatic compound degradation genes were repressed on decayed wood extract. Randomly barcoded transposon sequencing failed to identify a solitary catabolic pathway used by R. palustris, suggestive of substrate co-utilization, and surprisingly showed that genes involved with copper toxicity were essential. Finally, we found genes involved with biosynthesis of certain cofactors were non-essential on decayed wood extract, suggesting these nutrients were scavenged, and implicating these resources in supporting microbial communities in the environment. This study helps lay the foundation for a model fungal-bacterial system to study interactions that govern these relationships which will be valuable for understanding ecological interactions and industrially relevant co-culture systems.
Project description:The redox-sensing two-component signal transduction system, RegSR, in Rhodopseudomonas palustris has been shown to regulate an uptake hydrogenase in response to varying cellular redox states; however, its role is still largely undefined. Here, we used RNA sequencing to compare gene expression patterns in wild type R. palustris strain CGA010 to a ΔregSR derivative, CGA2023, under varying metabolic conditions. Growth conditions were chosen to utilize the different metabolic capabilites of R. palustris and, thus, present a variety of different redox challenges to the cell.
Project description:AIM: By adopting comparative transcriptomic approach, we investigated the gene expression of wood decomposing Basidiomycota fungus Phlebia radiata. Our aim was to reveal how hypoxia and lignocellulose structure affect primary metabolism and the expression of wood decomposition related genes. RESULTS: Hypoxia was a major regulator for intracellular metabolism and extracellular enzymatic degradation of wood polysaccharides by the fungus. Our results manifest how oxygen depletion affects not only over 200 genes of fungal primary metabolism but also plays central role in regulation of secreted CAZyme (carbohydrate-active enzyme) encoding genes. Based on these findings, we present a hypoxia-response mechanism in wood-decaying fungi divergent from the regulation described for Ascomycota fermenting yeasts and animal-pathogenic species of Basidiomycota.
