Abundances of keystone genes confer superior performance in hyperthermophilic composting. (15th December 2021)

• Record Type: Journal Article
• Authors: Cui, Peng; Ai, Chaofan; Xu, Zhongbing; Chen, Zhi; Yu, Zhen; Liao, Hanpeng; Zhou, Shungui
• Is Part Of: Journal of cleaner production. Volume 328(2021)
• Publication Date: 2021-12-15
• Subjects: Carbon degrading -- Composting performance -- Hyperthermophilic composting -- Keystone gene -- Nitrogen cycling; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2021.129589
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Large amounts of organic solid waste (OSW) originating from anthropogenic activities have imposed enormous pressure on the environment and human health. Hyperthermophilic composting ( h TC) exhibits superior performance in OSW disposal by providing advantages such as improved composting temperature, nitrogen conservation (NC), nitrous oxide mitigation and germination index (GI) over conventional thermophilic composting ( c TC). However, microbial communities have a central role in driving composting performance by mediating OSW component transformation, and it remains unclear how h TC communities drive improved performance. This study used GeoChip coupled with high-throughput sequencing data to investigate the variations in carbon (C)-degrading and nitrogen (N)-cycling genes and microbial communities and their linkages with performance indices in h TC and c TC, aiming to identify the keystone biotic drivers for the improved performance. The results indicated significant differences in the composition and structure profiles of the functional genes between the h TC and c TC treatments. 18 of 45 C-degrading genes exhibited significantly higher relative abundances during the hyperthermophilic phase in h TC (day 5) than in c TC. By comparison, 12 of 16 N-cycling genes showed significantly lower relative abundances in h TC than in c TC. These differences between h TC and c TC remained as the composting process proceeded but with a narrowed downward trend. These significantly shifted genes were the keystone genes dominating the improved performance of h TC, as indicated by a random forest model. Multiple statistical analyses suggested that the abundances of keystone genes continued to dominantly drive the improved performance after multiple biotic drivers were simultaneously considered in h TC. This study provides evidence that the abundance of keystone genes potentially plays a pivotal role in improving composting performance in h TC. Graphical abstract: Image 1 Highlights: Hyperthermophilic composting results in distinctive microbial function profile. Hyperthermophilic composting increases the relative abundances of C-degrading genes. Hyperthermophilic composting decreases the relative abundances N-cycling genes. The shifted genes drive the improved performance of hyperthermophilic composting.