Prenyltransferase that catalyzes the transfer of the geranylgeranyl moiety of geranylgeranyl diphosphate (GGPP) to the C3 hydroxyl of sn-glycerol-1-phosphate (G1P). This reaction is the first ether-bond-formation step in the biosynthesis of archaeal membrane lipids (By similarity). MTH_552 MTH_552 GGGPS_METTH Phosphoglycerol geranylgeranyltransferase 245 (S)-3-O-geranylgeranylglyceryl phosphate synthase Geranylgeranylglyceryl phosphate synthase MKVEDYFHDILRERKIHLTLIDPEEQTPEEAVEIARAAIRGGTDGIMLGGSTTDSSELDNTARALRENIDVPIILFPGNTTGVSRYADAIFFMSLLNSTNPYWIIGAQALGAATVKKMGIEALPMGYLVVEPGGTVGWVGDTKPVPRNKPDIAAAYAMAAEFLGMRLFYLEAGSGAPEHVPEEMIALVKRCTDQILIVGGGIRSGEDAARVAGAGADVVVTGTVVENSDNVEDKIREIVEGMGSV