Solid phase enzyme kinetics screening in microcolonies

摘要

A MicroColonyImager instrument and solid phase methods to screen cells expressing mutagenized enzymes for enhanced activity. The MicroColonyImager instrument and methods permit high throughput screening of enzyme libraries by time course analyses of single-pixels, using either absorption, fluorescence or FRET. This high throughput assay can detect small differences in enzyme rates within microcolonies grown at a nearly confluent density on an assay disk. Each microcolony is analyzed simultaneously at single-pixel resolution, requiring less than 100 ml substrate/measurement. By simultaneously assaying different substrates tagged with spectrally distinct chromogenic or fluorogenic reporters, the substrate specificity of an enzyme can be changed.