Isolation of a Putative Ribosome Inactivating Protein from Dried Roots ofTrichosanthes kirilowiiUsed in Traditional Chinese Medicine

A putative ribosome inactivating protein (RIP), named T 33, was isolated from dried roots of Trichosanthes kirilowii Maximovicz which are used in Traditional Chinese Medicine. After chromatographic enrichment a protein band with molecular mass of 33 kDa was found by SDS-PAGE. Partial amino acid sequences of this protein consisting of 8 - 33 amino acids reveal homology to highly conserved regions of different RIPs, but also indicate T 33 to be a novel type 2 RIP. Future heterologous expression of this protein will allow investigation of its biological activities in detail.