Chidambareswaren Mahadevan

Abstract Oxidation in extracts from agroinfiltrated leaves leads to browning and protein precipitation. Here we show that silencing of polyphenol oxidase (PPO) in Nicotiana benthamiana suppresses enzymatic browning and avoids crosslinking of endogenous proteins such as RuBisCo. PPO silencing does not impact plant growth or development and may also enhance transient gene expression.

Abstract Eukaryotes produce a large number of cytochrome P450s that mediate the synthesis and degradation of diverse endogenous and exogenous metabolites. Yet, most of these P450s are uncharacterized and global tools to study these challenging, membrane-resident enzymes remain to be exploited. Here, we applied activity profiling of plant, mouse and fungal P450s with chemical probes that become reactive when oxidized by P450 enzymes.