Fig. 3: Mapping g2ps1 mutant catalysis through metabolic biosensing.

a Overview of the slide (75 mm × 25 mm) for single variant µMS comprising 10,000 wells grouped in 100 blocks of 100 wells (magnified blue box), scale bar 1 mm. Each circular well is paired with electrodes for printed droplet trapping (red box) and has a rounded profile that concentrates desiccated metabolites to the center (green). b µMS generates a spatial image of the substrate in which each pixel contains a full m/z spectrum. c Well spectra are extracted and clustered into four groups using UMAP. Mutants of interest are recovered, sequenced, and overlaid on the clusters as black dots. Inset shows the reference strain based on known print locations. d Heat maps for m/z 127 and 189 indicate high production of TAL in the upper and reference clusters, and high production of AHP in the lower cluster. Source data are provided in Supplementary Data 1.