Impact of Phanerochaete chrysosporium on the Functional Diversity of Bacterial Communities Associated with Decaying Wood

PLoS One. 2016 Jan 29;11(1):e0147100. doi: 10.1371/journal.pone.0147100. eCollection 2016.

Abstract

Bacteria and fungi naturally coexist in various environments including forest ecosystems. While the role of saprotrophic basidiomycetes in wood decomposition is well established, the influence of these fungi on the functional diversity of the wood-associated bacterial communities has received much less attention. Based on a microcosm experiment, we tested the hypothesis that both the presence of the white-rot fungus Phanerochaete chrysosporium and the wood, as a growth substrate, impacted the functional diversity of these bacterial communities. Microcosms containing sterile sawdust were inoculated with a microbial inoculum extracted from a forest soil, in presence or in absence of P. chrysosporium and subsequently, three enrichment steps were performed. First, bacterial strains were isolated from different microcosms previously analyzed by 16S rRNA gene-based pyrosequencing. Strains isolated from P. chrysosporium mycosphere showed less antagonism against this fungus compared to the strains isolated from the initial forest soil inoculum, suggesting a selection by the fungus of less inhibitory bacterial communities. Moreover, the presence of the fungus in wood resulted in a selection of cellulolytic and xylanolytic bacterial strains, highlighting the role of mycospheric bacteria in wood decomposition. Additionally, the proportion of siderophore-producing bacteria increased along the enrichment steps, suggesting an important role of bacteria in iron mobilization in decaying-wood. Finally, taxonomic identification of 311 bacterial isolates revealed, at the family level, strong similarities with the high-throughput sequencing data as well as with other studies in terms of taxonomic composition of the wood-associated bacterial community, highlighting that the isolated strains are representative of the wood-associated bacterial communities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria / classification
  • Bacteria / genetics*
  • Bacteria / metabolism
  • Biodegradation, Environmental
  • Biodiversity
  • Ecosystem
  • Fagus / microbiology
  • Forests
  • High-Throughput Nucleotide Sequencing
  • Microbial Consortia / physiology*
  • Microbial Interactions / physiology
  • Phanerochaete / physiology*
  • Phylogeny*
  • RNA, Ribosomal, 16S / genetics
  • Soil Microbiology*
  • Wood / microbiology*

Substances

  • RNA, Ribosomal, 16S

Grants and funding

The UMR IaM is supported by a grant overseen by the French National Research Agency (ANR) as part of the "Investissements d'Avenir" program (ANR-11-LABX-0002-01, Lab of Excellence ARBRE). Agence Nationale de la Recherche ANR-09-BLAN-0012 http://www.agence-nationale-recherche.fr/. Funding was received by VH EK EG PFK. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.