Complement C2 (EC 3.4.21.43) (C3/C5 convertase) [Cleaved into: Complement C2b fragment; Complement C2a fragment]
1_MGPLM 6_ VLFCL 11_ LFLYP 16_ GLADS 21_ APSCP 26_ QNVNI 31_ SGGTF 36_ TLSHG 41_ WAPGS 46_ LLTYS 51_ CPQGL 56_ YPSPA 61_ SRLCK 66_ SSGQW 71_ QTPGA 76_ TRSLS 81_ KAVCK 86_ PVRCP 91_ APVSF 96_ ENGIY 101_ TPRLG 106_ SYPVG 111_ GNVSF 116_ ECEDG 121_ FILRG 126_ SPVRQ 131_ CRPNG 136_ MWDGE 141_ TAVCD 146_ NGAGH 151_ CPNPG 156_ ISLGA 161_ VRTGF 166_ RFGHG 171_ DKVRY 176_ RCSSN 181_ LVLTG 186_ SSERE 191_ CQGNG 196_ VWSGT 201_ EPICR 206_ QPYSY 211_ DFPED 216_ VAPAL 221_ GTSFS 226_ HMLGA 231_ TNPTQ 236_ KTKES 241_ LGRKI 246_ QIQRS 251_ GHLNL 256_ YLLLD 261_ CSQSV 266_ SENDF 271_ LIFKE 276_ SASLM 281_ VDRIF 286_ SFEIN 291_ VSVAI 296_ ITFAS 301_ EPKVL 306_ MSVLN 311_ DNSRD 316_ MTEVI 321_ SSLEN 326_ ANYKD 331_ HENGT 336_ GTNTY 341_ AALNS 346_ VYLMM 351_ NNQMR 356_ LLGME 361_ TMAWQ 366_ EIRHA 371_ IILLT 376_ DGKSN 381_ MGGSP 386_ KTAVD 391_ HIREI 396_ LNINQ 401_ KRNDY 406_ LDIYA 411_ IGVGK 416_ LDVDW 421_ RELNE 426_ LGSKK 431_ DGERH 436_ AFILQ 441_ DTKAL 446_ HQVFE 451_ HMLDV 456_ SKLTD 461_ TICGV 466_ GNMSA 471_ NASDQ 476_ ERTPW 481_ HVTIK 486_ PKSQE 491_ TCRGA 496_ LISDQ 501_ WVLTA 506_ AHCFR 511_ DGNDH 516_ SLWRV 521_ NVGDP 526_ KSQWG 531_ KEFLI 536_ EKAVI 541_ SPGFD 546_ VFAKK 551_ NQGIL 556_ EFYGD 561_ DIALL 566_ KLAQK 571_ VKMST 576_ HARPI 581_ CLPCT 586_ MEANL 591_ ALRRP 596_ QGSTC 601_ RDHEN 606_ ELLNK 611_ QSVPA 616_ HFVAL 621_ NGSKL 626_ NINLK 631_ MGVEW 636_ TSCAE 641_ VVSQE 646_ KTMFP 651_ NLTDV 656_ REVVT 661_ DQFLC 666_ SGTQE 671_ DESPC 676_ KGESG 681_ GAVFL 686_ ERRFR 691_ FFQVG 696_ LVSWG 701_ LYNPC 706_ LGSAD 711_ KNSRK 716_ RAPRS 721_ KVPPP 726_ RDFHI 731_ NLFRM 736_ QPWLR 741_ QHLGD 746_VLNFL
1: Precursor of the catalytic component of the C3 and C5 convertase complexes, which are part of the complement pathway, a cascade of proteins that leads to phagocytosis and breakdown of pathogens and signaling that strengthens the adaptive immune system (PubMed:12878586, PubMed:17027507, PubMed:18204047, PubMed:39914456). Component C2 is part of the classical, lectin and GZMK complement systems (PubMed:12878586, PubMed:17027507, PubMed:18204047, PubMed:39914456)
2: Catalytic component of the complement C3 and C5 convertase complexes (PubMed:12878586, PubMed:17027507, PubMed:18204047, PubMed:6906228). Following complement activation, recruited to the surface of pathogens by complement C4b opsonin to form the C3 convertase, or C3b and C4b opsonins to form the C5 convertase (PubMed:6611150, PubMed:6906228). As part of the C3 convertase, cleaves and activate C3 into C3a anaphylatoxin and C3b opsonin, the next components of the complement pathways (PubMed:14561755, PubMed:17027507). As part of the C5 convertase, cleaves and activate C5 into C5a anaphylatoxin and C5b component of the membrane attack complex (PubMed:12878586, PubMed:17027507, PubMed:18204047)