Genomic, Proteomic, and Biochemical Study of Pleurotus pulmonarius Secretome and Its Role in Biomass Saccharification

Pleurotus species include edible mushrooms that
grow on a range of lignocellulosic substrates by secreting hydrolytic
and oxidative enzymes. This flexibility offers opportunities to valorize
agro-industrial residues for sustainable production of food and biomaterials.
In this study, we analyzed the genome of Pleurotus
pulmonarius and its biocatalytic potential for lignocellulose
saccharification using proteomics and biochemical assays. The fungus
was cultivated on beechwood, corn stover, and xylose. Beechwood induced
the richest secretome with abundant oxidases. The corn stover secretome
had fewer proteins but was focused on carbohydrate-acting enzymes,
with abundant polysaccharide-degrading and accessory enzymes. Despite
lower enzyme diversity, corn stover secretome achieved higher lignocellulose
saccharification, further improved by oxidoreductase inhibition. Supplementing
an industrial cellulase cocktail with P. pulmonarius corn stover secretomes enhanced sugar release by 40%. These findings
highlight the dynamic enzymatic response of P. pulmonarius to lignocellulosic substrates and its potential in biomass valorization
and the design of enzymatic cocktails.