Discovery of Degradation Pathways in Microbial Communities Using Photoaffinity Labeling (PAL)

Lignin is the largest renewable aromatic resource and a promising feedstock for sustainable bioproduction. Currently, most efforts are focused on funneling lignin-derived aromatics to common intermediates such as protocatechuate or catechol. The above approach fails to explore the diverse lignin-derived aromatic degradation pathways.

The aim is to explore diverse lignin degradation pathways in nature and discover novel chemical transformations on lignin-derived aromatics by enzymes in microbial communities. This may help us funnel lignin to valuable bioproducts. To discover new pathways, we will use photoaffinity labeling (PAL).

PAL is a biochemical technique that provides information about the ligand-protein interactions in the cell. A lignin-derived aromatic with PAL can be fed to microbial communities. The PAL will label the enzymes using the compound of interest as the substrate. Subsequent enrichment and proteomics will help us identify enzymes processing the labeled aromatics.

When used at high throughput, the workflow will help us explore rich aromatic degradation chemistry in microbial communities and help us funnel the lignin-derived aromatics to valuable bio-products. The first steps include synthesizing and testing the probes in Pseudomonas Putida KT2440, Achromobacter isolate, and Rhodosporidium toruloides.