One Enzyme, Twice the Ethanol

Brazilian scientists discovered CelOCE, a metalloenzyme that may double cellulose-to-ethanol conversion efficiency using agricultural waste

19 Jun 2026

Brazilian researchers have identified a metalloenzyme that could reshape second-generation ethanol production. Scientists at CNPEM discovered CelOCE, an enzyme operating through a previously unknown mechanism, and published their findings in Nature on May 29, 2025. The timing matters. Current industrial processes convert cellulose at just 60 to 70%, a persistent bottleneck that has constrained biofuel output for decades and left enormous energy potential locked inside agricultural residues that producers already generate at scale.

CelOCE works through substrate binding and oxidative cleavage, a mode of action researchers had not previously observed in cellulose breakdown. Mário Murakami, head of CNPEM's biocatalysis and synthetic biology research group, put it plainly. "We've identified a metalloenzyme that enhances cellulose conversion through a previously unknown mechanism of substrate binding and oxidative cleavage," he said, adding that the find opens entirely new avenues for industrial enzyme engineering.

Doubling conversion efficiency would mean far greater energy yield from agricultural residues like sugarcane bagasse and corn straw. Both are abundant byproducts of existing harvests, so producers would not need new land or new crops to scale output. That changes the economics considerably. CNPEM says CelOCE is ready for immediate industrial integration, sidestepping the lengthy pilot phases that typically slow the commercial adoption of laboratory breakthroughs.

For biofuel producers, the implications reach straight to the margin. Higher cellulose conversion means more ethanol extracted from every ton of waste material, compressing production costs while expanding supply. Sugarcane-heavy markets across South America stand to gain most immediately, though the enzyme's applicability to corn straw positions it for rapid uptake in North American and European markets as well. Early adopters could secure a durable cost advantage as demand for low-carbon fuels continues to accelerate.