Bacterial communities involved directly or indirectly in the anaerobic degradation of cellulose
- 133 Downloads
To determine bacterial communities involved, directly or indirectly, in the anaerobic degradation of cellulose, we conducted a microcosm experiment with soil treated with 13C-cellulose, 12C-cellulose, or without cellulose with analyses of DNA-based stable isotope probing (DNA-SIP), real-time quantitative PCR, and high-throughput sequencing. Firmicutes, Actinobacteria, Verrucomicrobia, and Fibrobacteres were the dominant bacterial phyla-degrading cellulose. Generally, bacteria possessing gene-encoding enzymes involved in the degradation of cellulose and hemicellulose were stimulated. Phylotypes affiliated to Geobacter were also stimulated by cellulose, probably due to their role in electron transfer. Nitrogen-fixing bacteria were also detected, probably due to the decreased N availability during cellulose degradation. High-throughput sequencing showed the presence of bacteria not incorporating 13C and probably involved in the priming effect caused by the addition of cellulose to soil. Collectively, our findings revealed that a more diverse microbial community than expected directly and indirectly participated in anaerobic cellulose degradation.
KeywordsCellulose degradation Paddy soil Cellulolytic bacteria Syntrophic microorganisms Nitrogen-fixing bacteria Priming effect
The authors thank Ms. Yushan Zhan for her assistance of material preparation before the experiment. Authors also thank Editor-in-Chief Prof. Paolo Nannipieri and three anonymous reviewers for their constructive comments and suggestions, which greatly improved the manuscript.
This work was supported by the National Natural Science Foundation of China (Project Nos. 41430859, 41771294, 41671267, and 41471208), the CAS Strategic Priority Research Program Grant (Project No. XDB15020103), National Key R&D Program (2016YFD0200306), Research Program for Key Technologies of Sponge City Construction and Management in Guyuan City (Grant No. SCHM-2018), and Knowledge Innovation Program of Chinese Academy of Sciences (Grant No. ISSASIP1639).
- Bernard L, Mougel C, Maron PA, Nowak V, Lévêque J, Henault C, Haichar FZ, Berge O, Marol C, Balesdent J (2007) Dynamics and identification of soil microbial populations actively assimilating carbon from 13C-labelled wheat residue as estimated by DNA- and RNA-SIP techniques. Environ Microbiol 9:752–764CrossRefGoogle Scholar
- Hori T, Muller A, Igarashi Y, Conrad R, Friedrich MW (2010) Identification of iron-reducing microorganisms in anoxic rice paddy soil by 13C-acetate probing. ISME J 4:267–278Google Scholar
- Nottingham AT, Hicks LC, Ccahuana AJ, Salinas N, Bååth E, Meir P (2018) Nutrient limitations to bacterial and fungal growth during cellulose decomposition in tropical forest soils. Biol Fertil Soils 54:219–228Google Scholar
- Paul EA, Clark FE (1989) Soil microbiology and biochemistry. Academic Press, London, pp 93–97Google Scholar
- Richmond PA (1991) Occurrence and functions of native cellulose. In: Haigler CH, Weimer JP (eds) Biosynthesis and biodegradation of cellulose. Dekker, New York, pp 5–23Google Scholar
- Saiz-Jimenez C (1996) The chemical structure of humic substances: recent advances. In: Piccolo A (ed) Humic substances in terrestrial ecosystems. Elsevier, Amsterdam, pp 1–45Google Scholar