Peanut worms: a sulphate reducing bacteria repellent!

Sedimental bacterial communities play an important ecological and biogeochemical role in tidal flat ecosystems for nutrient recycling and pollutant degradation. Bioturbation by benthic organisms can reshape the biological and physiochemical properties of the sediment, manipulating the distribution and composition of bacterial communities. The ecological role of sipunculid worms in reshaping bacterial community composition and biogeochemical cycles in intertidal zones is not currently well understood. Li et al. (2019) used high-throughput sequencing to investigate the microbial communities and their response to bioturbation by Sipunculus nudus at different depths in a sandy tidal flat.

This study demonstrates that bioturbation by S. nudus plays and important role in reshaping the bacterial community composition in intertidal regions, from the bottom to the surface layer. Interestingly, sulphate-reducing bacteria (SRB) were the most abundant taxa, indicating that sulphate reduction is the main process in the sandy tidal flat. The abundances of Desulfococcus and LCP-6 in the non-burrow sediment were greater than in the burrow sediment, suggesting that anoxic conditions are more suitable for Desulfococcus and LCP-6 when the activity of S. nudusis absent. In previous research, the accumulation of sulphide has been linked to the low biodiversity of S. nudus and reduced growth rates; and so, sulphate metabolism in the sediment and burrows require further study to understand the interaction between SRB and the presence of peanut worms further.

Li, J., Hu, R., Guo, Y., Chen, S., Xie, X., Qin, J.G., Ma, Z., Zhu, C. and Pei, S., 2019. Bioturbation of peanut worms Sipunculus nudus on the composition of prokaryotic communities in a tidal flat as revealed by 16S rRNA gene sequences. MicrobiologyOpen, p.e802.