Immunogen sequence: GFITDPVVLS PKDRVRDVFE AKARHGFCGI PITDTGRMGS RLVGIISSRD IDFLKEEEHD CFLEEIMTKR EDLVVAPAGI TLKEANEILQ RSKKGKLPIV NEDDELVAII ARTDLKKNRD YPLASKD. This gene encodes the rate-limiting enzyme in the de novo guanine nucleotide biosynthesis. It