From A to Zera Fusions
“We are working on multiple applications of our assembler peptide, one being a versatile bioprocess for protein manufacture,” states Stefan Schmidt, Ph.D., vp of technology at ERA Biotech. The company’s technology is based on the use of the g-zein protein in maize. This storage protein takes part in protein body formation, notably in the endosperm of the corn plant.
ERA’s technology involves the construction of a fusion protein between the Zera assembly peptide and a target recombinant protein gene. As the protein bodies are formed in the course of cellular biosynthesis, the Zera fusion protein is sequestered inside the storage organelle where it is well-folded and protected from proteolysis. These StorPro Organelles can be engineered into mammalian cells or other eukaryotic hosts without affecting the host cell’s viability.
This technology is of particular value in protecting unstable or difficult to express recombinant proteins, such as peptides, and antimicrobials from normal host-cell metabolism. Purification and removal of contaminants is particularly easy, Dr. Schmidt says. Major advantages of the system include compatibility with existing vector and expression enhancing systems, protection of both cell and protein by encapsulation, simplifying the downstream process, thus leading to a shorter time frame and lower costs of goods, he adds.
“We are currently pushing product applications,” Dr. Schmidt says. The expanding platform technology of the company will embrace cleavage systems and affinity binder options, a tool box of vectors and enhancers, and a multihost, high-throughput system.
“The Zera format is especially versatile, in that it could allow various administrations of the fusion proteins in the StorPro bodies, as well as traditional application of the highly purified recombinant protein.”