Immunogen sequence: KHLDKFSSYH VKTAFFHVCT QNPQDSQWDR KDLGLCFDNC VTYFLQCLRT EKLENYFIPE FNLFSSNLID KRSKEFLTKQ IEYER. cGAS (Cyclic GMP-AMP synthase) is a nucleotidyltransferase that catalyzes the formation of cyclic GMP-AMP (cGAMP) from ATP and GTP and play