Project Summary This research will significantly expand the PI’s unique research program in quantitative bacterial physiology from the exclusive focus on the model organism Escherichia coli during the past decade to a variety of species across the bacterial phylogeny, including Vibrio, Pseudomonas, Bacteroides, Mycobacterium, and Bacillus. Transcriptomic, proteomic, and metabolomic approaches will be applied to these bacterial species for a spectrum of conditions with emphasis on cementing absolute abundances of the measured quantities as well as the rate of synthesis and turnover. For each species investigated, we will replicate previous studies for E. coli to derive both coarse-grained phenomenological models as well as establish relation to molecular regulation. We will also develop methods for inter-species comparisons at the quantitative level. These studies will not only generate a vast amount of useful quantitative data and models for bacteria of