The ribosome is a large cellular machine responsible for protein synthesis. While much of the research surrounding ribosome have been centered on protein translation, comparatively little is known about how these machines assemble in the first place. Recently, we have developed a novel genetic approach that places an r-protein of interest under the control of a titratable promotor to modulate the level and timing of r-protein expression with minimal perturbation to the host. The consequences of limited r-protein expression can then be monitored using quantitative mass spectrometry (QMS) and cryo-electron microscopy (cryo-EM). I am working on expanding our r-protein limitation strain library and characterizing their ribosome assembly intermediates in order to delineate a comprehensive relationship between ribosome assembly pathways under distinct r-protein limitation stresses. Also, I am developing a workflow to integrate QMS with cryo-EM structural information and developing strategies to push the boundaries of current cryo-EM classification software to take full advantage of the highly heterogeneous ribosome assembly intermediate datasets.