Metagenomics and metatranscriptomics uncover the microbial community associated with high S0 production in a denitrifying desulfurization granular sludge reactor. (15th September 2021)

• Record Type: Journal Article
• Authors: Li, Wei; Gao, Jian; Zhuang, Jin-long; Yao, Gen-ji; Zhang, Xu; Liu, Yong-di; Liu, Qi-kai; Shapleigh, James P.; Ma, Liang
• Is Part Of: Water research. Volume 203(2021)
• Publication Date: 2021-09-15
• Subjects: Denitrifying sulfide oxidation -- S0 production -- Microflora -- Meta-omics; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2021.117505
• Languages: English
• ISSNs: 0043-1354

Abstract

Highlights: A denitrification desulfurization process inoculated AnAGS was built. High quality S 0 was obtained in the efficient denitrification desulfurization reactor. Meta-omics indicated that SOB utilizing SQR were accounted for high S 0 production. An unexpected enrichment in methanogens was observed. High activity of Stickland fermentation, likely aiding performance stability. Abstract: The denitrification desulfurization process is a promising technology for elemental sulfur (S 0 ) production from sulfide containing wastewater. However, the microbial community associated with high S 0 production still is not well studied. This study describes an efficient denitrification S 0 production bioreactor based on inoculation with anaerobic granular sludge. At an optimal S/N molar ratio of 7:2, 80 % of the influent sulfide was transformed to high quality elemental sulfur with a purity of 92.5% while the total inorganic nitrogen removal efficiency was stable at ∼80%. Metatranscriptomic analysis found that community expression of the gene encoding the sulfide-quinone reductase (SQR) was 10-fold greater than that of the flavocytochrome- c sulfide dehydrogenase subunit B ( fccB) . Moreover, the expression level of SQR was also significantly higher than the Dsr gene encoding for dissimilatory sulfate reductase, which encodes a critical S 0 oxidation enzyme. Metagenomic binning analysis confirmed that sulfide-oxidizing bacteria (SOB) utilizing SQR were common in the community and most likely accounted for high S 0 production. An unexpected enrichment in methanogens and high expression activity of bacteria carrying out Stickland fermentation as well as in other bacteria with reduced genomes indicated a complex community supporting stable sulfide oxidation to S 0, likely aiding in performance stability. This study establishes this treatment approach as an alternative biotechnology for sulfide containing wastewater treatment and sheds light on the microbial interactions associated with high S 0 production. Graphical abstract: Image, graphical abstract