Community Structure, Assembly and Interactions of Nitrite-Oxidizing Bacteria in Sediments of the Eastern China Marginal Seas.

Nitrite oxidation, a pivotal process in the nitrogen cycle driven by microorganisms, is primarily carried out by nitrite-oxidizing bacteria (NOB). While extensive studies on have been conducted in terrestrial habitats, knowledge of in marine sediments remains limited. Therefore, we employed high-throughput sequencing analysis to systematically explore the community structure, assembly processes and potential interactions of in the eastern China marginal seas. Our results exhibit pronounced spatial heterogeneity in communities across seas. Widespread distribution of taxa was observed, with lineage II emerging as the most important group in this study. Based on the neutral community model (NCM), normalized stochasticity ratio (NST) and beta nearest-taxon-index (βNTI) analysis, deterministic processes predominantly shaped the community assembly of . Complex interspecies interactions among were observed with molecular ecological network analysis, and the community in the East China Sea showed the highest complexity, while the community displayed the greatest stability in the South Yellow Sea. In addition, the communities were notably influenced by geographic distances and environmental factors, including salinity, temperature, dissolved oxygen concentration and dissolved inorganic nutrient concentration. These results may expand our understanding of in marine environments and enhance our insights into the marine nitrogen cycle.