Method for selecting stabilized proteins

US6468746B1 · kind B1 · utility

Assignee

• BASF SE

Inventors

• Volker Sieber · Dresden, DE
• Franz Schmid · Bayreuth, DE

Key dates

• Filing date: Jul 23, 1999
• Grant date: Oct 22, 2002
• Expiry date: Jul 23, 2019

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C12N15/1037
• WIPO field: Biotechnology
• WIPO sector: Chemistry

Abstract

Proteins to be stabilized are incorporated between two domains of the gene III protein of a bacteriophage. A mixture of phages with a large repertoire of mutants of the protein to be stabilized in the gene III protein is treated with proteases. The phages which present the least stable variants of the protein lose their infectivity fastest, whereas those whose genes code for stabilized variants of the protein retain their infectivity longest. Infection of bacterial cells with the phages treated with proteases and multiplication thereof leads to enrichment of the phages which comprise genes of stabilized variants of the mutagenized protein. The sequences of the most stable variants of the protein are obtained in this way from the genomes of the phages remaining after several rounds of phage cultivation, proteolysis and reinfection.