Bacterial communities in the phaseⅡ of Agaricus bisporus compost by denaturing gradient gel electrophoresis

Abstract:

[Objective] We studied the bacterial community during Agaricus bisporus composting phase II, to develop a quick and accurate method by modern molecular ecology technique for dynamic inspection on bacterial community during A. bisporus composting. [Methods] We selected seven A. bisporus compost samples from different stages of phase II. We used PCR to amplify the V3 regions of the 16S ribosomal DNA from those samples. We analyzed PCR products by denaturing gradient gel electrophoresis. [Results] The denaturing gradient gel electrophoresis profile showed a dramatic change of bacterial communities which related to the process of phase II of A. bisporus compost. DNA sequencing of the dominant bands of denaturing gradient gel electrophoresis profile indicated that the bacterial diversity in the phase II of A. bisporus compost was much higher than that studied by traditional method cultured-based approach. We found not only the genus of Bacillus, commonly believed to dominate high temperature compost, but also some new groups belonged to the class of Bacilli such as Trichococcus, Planococcus, Caryophanon and even the γ-subgroup of Proteobacteria. At the same time, some sequences were related to the genus of Thermus thermophilus and α-subdivision of Proteobacteria which were only recently reported in the hot compost. Several sequences display extremely low similarity with the cultivated species in the GenBank, indicating high diversity of uncultivated bacteria in the process of A. bisporus composting. [Conclusion] We found distinctly changes on bacterial communities during A. bisporus composting phase II by denaturing gradient gel electrophoresis profile. Also we found a lot of presently uncultured bacteria species during A. bisporus composting. And what then? Meaningful of your study? I don’t see any indications/conclusion from your study, as you stated in the beginning of the abstract.