Proteins represent the major source for organic nitrogen in the ocean. Yet the identification of individual proteins and important mechanisms controlling their preservation has been stalled by the analytical and mathematical challenges in deciphering the vast suite of possible structures and complex suite of degradation products.
In this study, researchers at the Chesapeake Biological Laboratory and the University of Washington will conduct a novel interdisciplinary study to harness and integrate recent developments and advances in biomedical proteomics and bioinformatics to follow the geochemical fate of proteins in marine systems. The integration of proteomics approaches to geochemical analysis is expected to allow the research team to identify individual proteins in both living materials and their detrital products -- the process involved in transforming proteins into biomarkers of both organic sources and the catalytic (i.e. enzymatic) agents responsible for their degradation.
The project has three major goals:
1. Identification of the dominant proteins expressed in autotrophs prior to becoming detritus. These proteins represent the primary precursors for long term protein preservation and knowledge of their amount, distribution and amino acid signatures are needed to follow subsequent alterations.
2. Identification of peptides and modified products resulting from algal protein degradation and their interaction in the complex matrices of particles and sediments. With these observed sequence tags, the researchers propose to assign individual protein homologies, functions, and sources across a range of environments.
3. Application of advances in proteomics (including database mining and bioinformatics) to identify specific structures (e.g. Ã¡-helices, Ã¢-sheets, hydrophobic cores) or chemical modifications (glycation, phosphorylation etc.) that are selectively retained during the degradation process and act as mechanisms for long term preservation of organic nitrogen.
Broader Impacts: This project will feature several approaches to provide for interdisciplinary student training in marine chemistry and proteomics as well as disseminate results to a broad audience. In the more traditional role, this project will support a doctoral student and key postdoctoral fellow. Undergraduate students will be involved in the summer at CBL through an active on-site REU program. The team will expand the impact of this work to the broader educational community through science teacher training.