Variation of bacterial community associated withPhaeodactylum tricornutum in response to different inorganic nitrogen concentrations

• Published in: 海洋学报（英文版） Vol. 37; no. 12; pp. 118 - 128
• Main Authors: SHI Feng, WEI Xiaoxue, FENG Jianfeng, SUN Yingxue, ZHU Lin
• Format: Journal Article
• Language: English
• Published: Key Laboratory of Pollution Process and Environmental Criteria of Ministry of Education and Tianjin Key Laboratory of Environmental Remediation and Pollution Control,College of Environmental Science and Engineering,Nankai University,Tianjin 300350,China 2018
• Subjects: bacterial diversity; community structure; Gammaproteobacteria; Phaeodactylum tricornutum; nitrogen forms; nitrogen concentrations
• ISSN: 0253-505X
• DOI: 10.1007/s13131-018-1272-7

Specific bacterial communities interact with phytoplankton in laboratory algal cultures. These communities influence phytoplankton physiology and metabolism by transforming and exchanging phytoplankton-derived organic matter. Functional bacterial groups may participate in various critical nutrients fluxes within these associations, including nitrogen (N) metabolism. However, it is unclear how bacterial communities and the associated algae respond to changes of phycosphere N conditions. This response may have far-reaching implications for global nutrient cycling, algal bloom formation, and ecosystem function. Here, we identified changes in the bacterial communities associated withPhaeodactylum tricornutum when co-cultured with different forms and concentrations of N based on the Illumina HiSeq sequencing of 16S rRNA amplicons. Phylogenetic analysis identified Proteobacteria and Bacteroidetes as the dominant phyla, accounting for 99.5％ of all sequences. Importantly, bacterial abundance and community structure were more affected by algal abundance than by the form or concentration of inorganic N. The relative abundance of three gammaproteobacterial genera (Marinobacter,Algiphilus andMethylophaga) markedly increased in N-deficient cultures. Thus, some bacterial groups may play a role in the regulation of N metabolism when co-cultured withP. tricornutum.