A Major Step in Opening the Black Box of High-Molecular-Weight Dissolved Organic Nitrogen by Isotopic Labeling of Synechococcus and Multibond Two-Dimensional NMR

Analytical Chemistry
Xiaoyan CaoKlaus Schmidt-Rohr

Abstract

Dissolved organic nitrogen (DON) comprises the largest pool of fixed N in the surface ocean, yet its composition has remained poorly constrained. Knowledge of the chemical composition of this nitrogen pool is crucial for understanding its biogeochemical function and reactivity in the environment. Previous work has suggested that high-molecular-weight (high-MW) DON exists only in two closely related forms, the secondary amides of peptides and of N-acetylated hexose sugars. Here, we demonstrate that the chemical structures of high-MW DON may be much more diverse than previously thought. We couple isotopic labeling of cyanobacterially derived dissolved organic matter with advanced two-dimensional NMR spectroscopy to open the "black box" of uncharacterized high-MW DON. Using multibond NMR correlations, we have identified novel N-methyl-containing amines and amides, primary amides, and novel N-acetylated sugars, which together account for nearly 50% of cyanobacterially derived high-MW DON. This study reveals unprecedented compositional details of the previously uncharacterized DON pool and outlines the means to further advance our understanding of this biogeochemically and globally important reservoir of organic nitrogen.

References

Jan 1, 1977·Annual Review of Microbiology·R Y Stanier, G Cohen-Bazire
May 11, 2000·Journal of Biomolecular NMR·A McDermottE K Paulsen
May 14, 2005·Science·Lihini I AluwihareCarl G Johnson
Apr 17, 2007·Journal of Natural Products·Tianying AnKathleen S Rein
Apr 20, 2007·Journal of Natural Products·Kerry L McPhailWilliam H Gerwick
Jul 23, 2009·Journal of Natural Products·Elmi N ZainuddinSabine Mundt
Nov 19, 2009·Journal of Agricultural and Food Chemistry·Xiaowen Fang, Klaus Schmidt-Rohr

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