Spectral count data and QSpec statistical analyses for key nitrogen metabolism, urea cycle, and spermine synthesis proteins identified in all experiments.

Each replicate analysis (i.e. 1, 2, 3, 4) is indicative of the summation of spectral counts for that particular protein identified in 4 gas phase fractions (GPFs). Spectral counts resulting from triplicate analytical cycles of PAcIFIC were added together to provide a final count for the PAcIFIC analysis. In order to be considered significantly up or down regulated two criteria were met by QSpec: Bayes factor >10, and log2(−Fe/+Fe)>0.5. Proteins that do not have QSpec information were only identified using the data-independent PAcIFIC method and could not be statistically evaluated. This list does not include all proteins involved in nitrogen metabolism (e.g. amino acids biosynthesis and degradation).