Polyphenol oxidase depletion in Nicotiana benthamiana enhances recombinant protein purification and preserves native protein integrity

Journal article

Summary: Agroinfiltration of Nicotiana benthamiana is widely used for recombinant protein production in plant science and molecular pharming, but enzymatic browning and native protein crosslinking during extraction may limit protein integrity and purification efficiency. We generated genome‐edited N. benthamiana lines lacking two polyphenol oxidases (PPOs) and analyzed protein integrity, enzymatic activity profiles, and recombinant protein purification under non‐denaturing extraction conditions. PPO‐deficient plants showed reduced browning and native protein crosslinking, preserved endogenous proteins at their predicted molecular weights, displayed increased detectable enzyme activities, and achieved a significantly higher recovery and improved purity of a transiently expressed recombinant protein. These findings identify PPO‐mediated oxidation as a major bottleneck during protein extraction and demonstrate that PPO depletion enhances recombinant protein purification while preserving native protein integrity.

Authors: Zheng, K; Kaschani, F; Watts, EC; Kaiser, M; van der Hoorn, RAL

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Wiley
• Journal: New Phytologist
• Article number: nph.71262
• Publication date: 2026-05-24
• Acceptance date: 2026-04-09
• DOI: 10.1111/nph.71262
• EISSN: 1469-8137
• ISSN: 0028646X, 0028-646X
• Language: English
• Keywords: biotechnology; crosslinking; Nicotiana benthamiana; polyphenol oxidase; molecular pharming; agroinfiltration