Depth-related cycling of suspended nitrogen- containing lipids in the northeast Atlantic

• Published in: Organic Geochemistry
• Main Authors: Gašparović, Blaženka, Penezić, Abra, Lampitt, Richard S., Sudasinghe, Nilusha, Schaub, Tanner
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2017
• Subjects: Chemistry; Marine Science; North Atlantic; Northeast Atlantic
• Online Access: http://fulir.irb.hr/4040/; http://fulir.irb.hr/4040/1/44_OG_2017_N-lip.docx; https://www.sciencedirect.com/science/article/pii/S0146638017302012; https://doi.org/10.1016/j.orggeochem.2017.07.008

We utilized high resolution Fourier transform ion cyclotron resonance mass spectrometry (FT- ICR MS) to describe the depth-dependent distribution and molecular nature of nitrogen containing lipids (N-lipids) from suspended particles in an oceanic environment. Samples were collected at the Porcupine Abyssal Plain (PAP) sustained observatory in the northeast Atlantic (49.0°N, 16.5°W). Approximately 12.5% of FT-ICR MS observed lipids contain N. Only 19% of the lipids we recorded have elemental compositions that match those in the Nature Lipidomics Gateway database. Our results illustrate: (i) the proportional and selective accumulation of N-lipids with increased depth (ii) that N-lipids which contain phosphorus are more stable than those without P (iii) the majority of the deep Atlantic unsaturated N- lipids are highly unsaturated and (iv) there is depth-related increase in the saturated N- lipids which indicates that saturation is an important process for the export of lipid N and C to the deep ocean. These observations provide a description of N-lipid characteristics, transformation and preservation potential through the water column in the mesotrophic area of the North Atlantic Ocean.