Cyclotide proteins and precursors from the genus Gloeospermum: Filling a blank spot in the cyclotide map of Violaceae

Identification of cyclotide proteins and mRNAs expand the distribution and structural diversity of this family of circular and cystine knotted proteins. The first indication for their biosynthesis in Violaceae is revealed in the form of expression of oxidative folding enzymes protein-disulfide isomerase and thioredoxin.