Probing the formation of anhydrovinblastine in Catharanthus roseus by single-cell mass spectrometry

Abstract

Anhydrovinblastine, derived from the periwinkle plant Catharanthus roseus, is the direct precursor of vinblastine that is an important drug to treat a number of types of cancer. Insights into the formation mechanism of anhydrovinblastine at the cell level is beneficial for improving the industrial production of anticancer drugs. Herein, metal microneedle was modified for extracting single-cell metabolites of Catharanthus roseus, and then the microneedle was directly served as emitter of electrospray ionization for direct mass spectrometry analysis of single-cell metabolites. Sampling efficiency of microneedle with different surface modifications were compared. Different cells in stem, root, and leaf of Catharanthus roseus were also investigated. Our results showed that two key monomeric precursor molecules, vindoline and catharanthine, are from different cells in Catharanthus roseus and could mix to form anhydrovinblastine. This work shows a new method for probing the biosynthesis and formation of bioactive molecules in living systems.