A new bacterium suitable for egg yolk immunoglobulin (IgY) large-scale chromatographic purification

CHACANA, P. A.; SCHADE, R.; TERZOLO, H. R.

Linz, Austria

Congreso; 11. Kongress über Alternativen zu Tierversuchen; 2003

Mitteleuropäische Gesellschaft für Alternativmethoden zu Tierversuchen

Usage of egg yolk immunoglobulins (IgY) is increasingly been adopted in many laboratories all over the world, due to its advantages concerning animal welfare and economy. A joint project between Germany and Argentina was carried out to develop this technology in Latin America and to improve IgY purification methods. To achieve this aim, an Argentinean research group working on bacteriology joined to a German team with long-term experience in IgY-Technology. Standard purification of IgG is carried out using affinity chromatography techniques based on Gram positive cell wall proteins, such as protein A of Staphylococcus aureus Cowan and protein G of Streptococcus suis. As these proteins have no affinity for IgY, we screened by an ELISA-based test different Gram positive bacteria: Staphylococcus, Streptococcus, Listeria, Bacillus, Corynebacterium, etc. Besides we included 21 different unclassified bacteria randomly chosen from soil isolates. Among them we find one atypical strain, belonging to the Serratia liquefaciens group. This strain has strong non-immunological IgY-binding. It was treated by sonication and protein extraction was performed to the soluble fraction. SDS Page and Western Blot were carried out and a single protein band was found to bind IgY. At present, further studies are being carried out searching for a new chromatographical IgY purification procedure based on this purified protein. Since this bacterium produces a luxuriant growth in standard culture media, it is a good candidate for the development of an inexpensive and specific affinity chromatography technique. This procedure could be applied at industrial scale, promoting a widespread use of IgY Technology.