Protein G expressed by human group C and G streptococci: cloning of gene and binding properties.

PCR generated fragments of the protein G gene from three GCS and GGS strains belonging to different G types had been cloned. The resulting PCR products were cloned into E. coli using expression vector pQE31. The clones, producing IgG-binding peptides were selected. Recombinant plasmids carried different inserts and encoded proteins of different size and with different binding properties.