New Protein Holds Promise For Use In Medicine

The world's first tumour fighting
bagel: SP-1
© Hebrew University of Jerusalem

In addition to being obtained from plant tissue, the protein can now also be produced in large quantities as a recombinant protein in bacteria, making it highly available for medicinal or other applications, say scientists of the Hebrew University of Jerusalem.

Called SP-1, the protein has a nanometric, "bagel-shaped,” circular form and is extremely stable. It has been found to be capable of surviving contact with enzymes that break down proteins or exposure to extreme conditions such as boiling, excessive acidity, salinity, organic solvents or detergent solutions.

According to Professor Altman and Shoseyov of the Hebrew University, the SP-1 protein serves to assist in creating a properly folded and functioning structure of other proteins within the plant's cells. The SP-1 also has the ability to assemble itself into a structure composed of twelve identical units, making it exceptionally resistant to extreme conditions. These qualities are rarely found among proteins and make the SP-1 a promising candidate for a multiplicity of uses in developing medicinal applications in the rapidly growing field of nanobiotechnology.

SP-1 nanocapsules will be capable of delivering cell-destroying drugs specifically to certain types of solid cancer tumours, say the scientists. The protein's tiny structure would enable this carrier to penetrate specifically into tumours without harming healthy tissue and thus enhance the effectiveness of chemotherapy.

This selective penetration is based on the fact that the blood vessels which feed tumours are considerably more porous than those reaching healthy cells. Therefore, the units of SP-1 carrying the drug would invade only the tumour-feeding blood vessels and not normal ones.; Source: Hebrew University of Jerusalem