Integrated FT-ICR-MS peptide dataset for the identification of deaminated peptides in marine dissolved organic matter across field and incubation experiments

This dataset contains Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS)–derived molecular assignments and peptide identifications in marine dissolved organic matter. The dataset includes samples from field campaigns (BATS and Harvey) and laboratory incubation experiments, covering a range of environmental conditions. All samples were processed using a consistent analytical workflow and matched against a custom peptide database (included in this dataset) to identify peptide-like molecular formulas, amino acid compositions, and deamination products. The dataset is organized into three components (BATS, Harvey, and Incubation), each containing sample-level peptide matchup files. Additional environmental data are provided where available, including dissolved organic carbon (DOC) measurements for BATS samples and complementary variables for Harvey samples, including amino acid measurements (LAA and DAA).