Volkensin, a type 2 ribosome-inactivating protein from the roots of Adenia volkensiiHarms (kilyambiti plant) was characterized both at the protein and nucleotide level by direct amino acid sequencing and cloning of the gene enco-ding the protein. Gene sequence analysis revealed that vol-kensin is encoded by a 1569-bp ORF (523 amino acid residues) without introns, withan internal linker sequence of 45 bp. Differences in residues present at several sequence positions (reproduced after repeated protein sequence ana-lyses), with respect to the gene sequence, suggest several isoforms for the volkensin A-chain
