Porphobilinogen deaminase (PBG-D) (EC 2.5.1.61) (Hydroxymethylbilane synthase) (HMBS) (Pre-uroporphyrinogen synthase)
1_MSGNG 6_ NAAAT 11_ AEENS 16_ PKMRV 21_ IRVGT 26_ RKSQL 31_ ARIQT 36_ DSVVA 41_ TLKAS 46_ YPGLQ 51_ FEIIA 56_ MSTTG 61_ DKILD 66_ TALSK 71_ IGEKS 76_ LFTKE 81_ LEHAL 86_ EKNEV 91_ DLVVH 96_ SLKDL 101_ PTVLP 106_ PGFTI 111_ GAICK 116_ RENPH 121_ DAVVF 126_ HPKFV 131_ GKTLE 136_ TLPEK 141_ SVVGT 146_ SSLRR 151_ AAQLQ 156_ RKFPH 161_ LEFRS 166_ IRGNL 171_ NTRLR 176_ KLDEQ 181_ QEFSA 186_ IILAT 191_ AGLQR 196_ MGWHN 201_ RVGQI 206_ LHPEE 211_ CMYAV 216_ GQGAL 221_ GVEVR 226_ AKDQD 231_ ILDLV 236_ GVLHD 241_ PETLL 246_ RCIAE 251_ RAFLR 256_ HLEGG 261_ CSVPV 266_ AVHTA 271_ MKDGQ 276_ LYLTG 281_ GVWSL 286_ DGSDS 291_ IQETM 296_ QATIH 301_ VPAQH 306_ EDGPE 311_ DDPQL 316_ VGITA 321_ RNIPR 326_ GPQLA 331_ AQNLG 336_ ISLAN 341_ LLLSK 346_ GAKNI 351_ LDVAR 356_QLNDA
1: As part of the heme biosynthetic pathway, catalyzes the sequential polymerization of four molecules of porphobilinogen to form hydroxymethylbilane, also known as preuroporphyrinogen (PubMed:18004775, PubMed:18936296, PubMed:19138865, PubMed:23815679). Catalysis begins with the assembly of the dipyrromethane cofactor by the apoenzyme from two molecules of porphobilinogen or from preuroporphyrinogen. The covalently linked cofactor acts as a primer, around which the tetrapyrrole product is assembled (PubMed:18936296). In the last step of catalysis, the product, preuroporphyrinogen, is released, leaving the cofactor bound to the holodeaminase intact (PubMed:18936296)