Nitrate Consumers in Arctic Marine Eukaryotic Communities: Comparative Diversities of 18S rRNA, 18S rRNA Genes, and Nitrate Reductase Genes.

ABSTRACT: For photosynthetic microbial eukaryotes, the rate-limiting step in NO₃^- assimilation is its reduction to nitrite (NO₂^-), which is catalyzed by assimilatory nitrate reductase (NR). Oceanic productivity is primarily limited by available nitrogen and, although nitrate is the most abundant form of available nitrogen in oceanic waters, little is known about the identity of microbial eukaryotes that take up nitrate. This lack of knowledge is especially severe for ice-covered seas that are being profoundly affected by climate change. To address this, we examined the distribution and diversity of NR genes in the Arctic region by way of clone libraries and data mining of available metagenomes (total of 4.24 billion reads). We directly compared NR clone ph

SUBMITTER: Comeau AM 

PROVIDER: S-EPMC6606872 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature