Changes in bacterial community of anthracene bioremediation in municipal solid waste composting soil

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in a municipal solid waste (MSW) composting site. Knowledge of changes in microbial structure is useful to identify particular PAH degraders. However, the microbial community in the MSW composting soil and its change associated with prolonged exposure to PAHs and subsequent biodegradation remain largely unknown. In this study, anthracene was selected as a model compound. The bacterial community structure was investigated using terminal restriction fragment length polymorphism (TRFLP) and 16S rRNA gene clone library analysis. The two bimolecular tools revealed a large shift of bacterial community structure after anthracene amendment and subsequent biodegradation. Genera Methylophilus, Mesorhizobium, and Terrimonas had potential links to anthracene biodegradation, suggesting a consortium playing an active role.

Fig. 1

Terminal restriction fragments (HaeIII digest) and their abundances in the Samples A and B

Fig. 2

Percentages of the clones affiliated with different phyla and sub-phyla to the total number of clones from Sample A or B Clones not classified to any known phylum are included as unclassified bacteria

Fig. 3

Phylogenetic tree of representative bacterial 16S rRNA gene sequences (beginning with ‘L’) within the genera of Methylophilus, Mesorhizobium, and Terrimonas from Sample B and reference sequences from GenBank Data in parentheses are GenBank accession numbers. Numbers at the nodes indicate the levels of bootstrap support based on neighbor-joining analysis of 1 000 resampled datasets