Microplate-based active/inactive 1° screen for biomass degrading enzyme library purification and gene discovery

We present here a whole-cell and permeabilized E. coli cell 1° active/inactive microplate screen for β-d-xylosidase, xylanase, endoglucanase, and ferulic acid esterase enzyme activities, which are critical for the enzymatic deconstruction of biomass for fuels and chemicals. Transformants from genomic or mutagenesis-derived libraries are screened using fluorophore-tagged substrate/enzyme activity pairs that are assayed directly in the protein expression host growth media using a minimum of specialized equipment and supplies.