Cellulose is all around us in nature – in grass stems, wood, even in some animals such as tunicates (sea squirt relatives). It’s part of our valued dietary fiber. We can’t digest any of it, so it’s part of our gastrointestinal whisk broom. We don’t have the enzymes for it. Of course, we also value the stability of cellulose in paper towels, pages of books (remember those things?), an cardboard boxes… and, pretty well in wood not touched by termites.
Contrarily, very few living beings can break down cellulose to sugars as a source of metabolic energy. Ruminant animals such as cows can do it in a four-stomach process. Well, not really themselves. They rely on microorganisms living in them, ultimately mostly bacteria.
A number of cellulose- splitting enzymes have been discovered and are even used industrially in making paper, textiles, and detergents. Clelton A. Santos and 31 colleagues in Brazil, France, and Denmark used the powerful methods of metagenomics to find new enzymes in complex mixes of organisms. Voila, with great data processing they found a copper-containing enzyme that breaking cellulose bonds while also making hydrogen peroxide – efficient!
This has been an outreach activity of the Las Cruces Academy, viewable at GreatSchools.org.
Source: Nature, 27 March 2025, pp. 1076 ff.
