Main content area

Shifts in the anammox bacterial community structure and abundance in sediments from the Changjiang Estuary and its adjacent area

Fu, Lulu, Chen, Yangyang, Li, Siqi, He, Hui, Mi, Tiezhu, Zhen, Yu, Yu, Zhigang
Systematic and applied microbiology 2019 v.42 no.3 pp. 383-396
anaerobic ammonium oxidation, bacterial communities, community structure, denitrifying bacteria, ecosystems, estuaries, genes, nitrifying bacteria, nitrogen cycle, phylogeny, phylotype, quantitative polymerase chain reaction, ribosomal RNA, sediments, sequence homology, total nitrogen, total organic carbon
Anaerobic ammonium oxidation (anammox) is an important process in marine nitrogen cycle. In this study, diverse anammox bacteria were identified in the sediments of the Changjiang (Yangtze) Estuary and its adjacent area. Specifically, the community characters of anammox bacteria in the studied area were studied by quantitative polymerase chain reaction (qPCR), as well as 16S rRNA gene- and functional gene (hzo)-based Roche 454 sequencing. The abundance of denitrifying bacteria detected by the nirS gene was greater than that of anammox bacteria. 16S rRNA and hzo gene fragments affiliating with known anammox bacterial lineages were recovered, and the two major phylotypes belonged to the Candidatus Scalindua (Ca. Scalindua) genus, with >90% sequence similarity. A phylogenetic analysis detected the Scalindua and Brocadia genera together with some anammox-like bacterial clusters, which suggested a higher diversity in the studied ecosystem than in open ocean environment, where only Scalindua genus was detected. A redundancy analysis (RDA) showed that total organic carbon (TOC) and total nitrogen (TN) content in sediments significantly influenced anammox bacterial abundance of. Spearman correlation analyses confirmed that the spatial variation in anammox bacterial abundance was highly correlated with TOC (P<0.01) and TN (P<0.01) contents in sediments.