Genex Corp. scientists and researchers at the NationalInstitutes of Health have elaborated the structure of abacterial protein that is useful for purifying IgG antibodiesand may have other uses as well.

According to a report in last week's issue of Science, theunusual structure of streptococcal protein G probably explainsits stability at high temperatures despite its lack of disulfidebonds. Protein G, a surface protein, doesn't melt until 87degrees C, Genex scientist David Filpula told BioWorld.

NMR spectroscopy revealed that the protein G domain thatbinds immunoglobulin has four strands of parallel beta pleats,with a long helix across them. This novel topology, togetherwith a lot of hydrogen bonding and a tightly packed and buriedcore that repels water, accounts for the unusual stability ofthis small domain, the scientists wrote.

The company's first recombinant product, protein G, couldprove useful in medical or material applications due to itsthermostability, Filpula said.

In February, Genex agreed to sell its protein G business toPharmacia LKB Biotechnology AB of Sweden.

-- Roberta Friedman, Ph.D.

(c) 1997 American Health Consultants. All rights reserved.