An aqueous extract of a sonicate of E. coli
(non-transformed strain K12 C600) has been used for immunization. This antibody reacts with at least 80 different E. coli
antigens in crossed immunoelectrophoresis, and also reveals a multitude of E. coli
antigens in immunoblotting from SDS polyacrylamide gel electrophoresis. Broad reactivity with E. coli
proteins (strains C600, HB101 and chi 1776 have been tested) makes it particularly well-suited for monitoring the purification of proteins made in E. coli
by genetic engineering.