Nitrifying niche in estuaries is expanded by the plastisphere

• Published in: Nature communications 2024-07, Vol.15 (1), p.5866-14, Article 5866
• Main Authors: Su, Xiaoxuan, Huang, Xinrong, Zhang, Yiyue, Yang, Leyang, Wen, Teng, Yang, Xiaoru, Zhu, Guibing, Zhang, Jinbo, Tang, Yijia, Li, Zhaolei, Ding, Jing, Li, Ruilong, Pan, Junliang, Chen, Xinping, Huang, Fuyi, Rillig, Matthias C., Zhu, Yong-guan
• Format: Article
• Language: English
• Subjects: 45/23; 45/77; 704/172/4081; 704/47/4112; Anthropocene; Bacteria - genetics; Bacteria - metabolism; Biofilms; Biofilms - growth & development; Biogeochemistry; Cycles; Ecosystem; Environmental factors; Estuaries; Estuarine ecosystems; Estuarine environments; Glass substrates; Humanities and Social Sciences; Labeling; Metagenomics; Microbiota - physiology; multidisciplinary; Niches; Nitrification; Nitrogen; Nitrogen - metabolism; Nitrogen Cycle; Nitrogen Isotopes - metabolism; Phylogeny; Science; Science (multidisciplinary); Seawater; Seawater - microbiology
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-50200-8

The estuarine plastisphere, a novel ecological habitat in the Anthropocene, has garnered global concerns. Recent geochemical evidence has pointed out its potential role in influencing nitrogen biogeochemistry. However, the biogeochemical significance of the plastisphere and its mechanisms regulating nitrogen cycling remain elusive. Using 15 N- and 13 C-labelling coupled with metagenomics and metatranscriptomics, here we unveil that the plastisphere likely acts as an underappreciated nitrifying niche in estuarine ecosystems, exhibiting a 0.9 ~ 12-fold higher activity of bacteria-mediated nitrification compared to surrounding seawater and other biofilms (stone, wood and glass biofilms). The shift of active nitrifiers from O 2 -sensitive nitrifiers in the seawater to nitrifiers with versatile metabolisms in the plastisphere, combined with the potential interspecific cooperation of nitrifying substrate exchange observed among the plastisphere nitrifiers, collectively results in the unique nitrifying niche. Our findings highlight the plastisphere as an emerging nitrifying niche in estuarine environment, and deepen the mechanistic understanding of its contribution to marine biogeochemistry. The biogeochemical roles of the plastisphere regulating N cycling are elusive. This study reveals the plastisphere as an emerging nitrifying niche, featured by distinct shifts in nitrifiers and potential substrate exchanges compared to seawater.