Edited by S. Casella
New evidence for bacterial diversity in the ascoma of the ectomycorrhizal fungus Tuber borchii Vittad.
Article first published online: 9 JAN 2006
FEMS Microbiology Letters
Volume 247, Issue 1, pages 23–35, June 2005
How to Cite
Barbieri, E., Bertini, L., Rossi, I., Ceccaroli, P., Saltarelli, R., Guidi, C., Zambonelli, A. and Stocchi, V. (2005), New evidence for bacterial diversity in the ascoma of the ectomycorrhizal fungus Tuber borchii Vittad. FEMS Microbiology Letters, 247: 23–35. doi: 10.1016/j.femsle.2005.04.027
- Issue published online: 9 JAN 2006
- Article first published online: 9 JAN 2006
- Received 31 January 2005, Revised 7 April 2005, Accepted 16 April 2005
- 16S rRNA gene;
- Tuber borchii Vittad.
The microbial community associated with ascocarps of the ectomycorrhizal fungus Tuber borchii Vittad. was studied by both cultivation and direct extraction of bacterial 16S rRNA gene (rDNA) sequence approaches. The inner part of six T. borchii ascoma collected in North-Central Italy was used to establish a bacterial culture collection and to extract the total genomic DNA to obtain a library of 16S rDNAs representative of the truffle bacterial community. Most of the isolates were affiliated to the gamma-Proteobacteria, mainly Fluorescent pseudomonads; some isolates were members of the Bacteroidetes group and Gram-positive bacteria, mostly Bacillaceae. The majority of the clones from the library were alpha-Proteobacteria showing significant similarity values, of greater than 97%, with members of the Sinorhizobium/Ensifer Group, Rhizobium and Bradyrhizobium spp. not previously identified as Tuber-associated bacteria. Only a few bacterial strains belonging to this bacterial subclass were found in the culture collection and isolated on a medium specific for Rhizobium-like organisms. A few clones were members of the beta- and gamma-Proteobacteria; as well as low and high G+C Gram-positive bacteria. Our findings clearly indicate that a dual approach increases the information obtained on the structural composition of a truffle bacterial community as compared to that derived via cultivation or direct recovery of 16S rDNA sequences alone.