To uncover potential regulatory roles for acetylation, we analyzed how acetylation patterns and abundances change between logarithmic and stationary phase growth in Bacillus subtilis. Using acetyllysine peptide enrichment followed by label-free mass spectrometry-based proteomics, we identified over 2,300 unique acetylation sites on proteins that function in many essential pathways. By comparing the changes in acetylation with total cell protein abundances, we discover a subset of specific acetylation events that are stoichiometrically regulated under different growth conditions.