pp-GalNAc-T initiates the formation of mucin-type O-linked glycans; UDP-GalNAc: polypeptide alpha-N-acetylgalactosaminyltransferases (pp-GalNAc-T) initiate the formation of mucin-type, O-linked glycans by catalyzing the transfer of alpha-N-acetylgalactosamine (GalNAc) from UDP-GalNAc to hydroxyl groups of Ser or Thr residues of core proteins to form the Tn antigen (GalNAc-a-1-O-Ser/Thr). These enzymes are type II membrane proteins with a GT-A type catalytic domain and a lectin domain located on the lumen side of the Golgi apparatus. In human, there are 15 isozymes of pp-GalNAc-Ts, representing the largest of all glycosyltransferase families. Each isozyme has unique but partially redundant substrate specificity for glycosylation sites on acceptor proteins.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  138 SVIIAFYNEAWSTLLRTIHSVLETSPAVLLKEIILVDDLSDRIYLKAQLETYISN-LERVRLIRTNKREGLVRARLIGAT 216
Cdd:cd02510   1 SVIIIFHNEALSTLLRTVHSVINRTPPELLKEIILVDDFSDKPELKLLLEEYYKKyLPKVKVLRLKKREGLIRARIAGAR 80

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  217 FATGDVLTFLDCHCECNTGWLEPLLERISRDETAIVCPVIDTIDWNTFEfYMQTGEPMIGGFDWRLTFQWHSVPKHERdR 296
Cdd:cd02510  81 AATGDVLVFLDSHCEVNVGWLEPLLARIAENRKTVVCPIIDVIDADTFE-YRGSSGDARGGFDWSLHFKWLPLPEEER-R 158

                       170       180       190       200       210       220       230       240
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  297 RTSRIDPIRSPTMAGGLFAVSKKYFQYLGTYDTGMEVWGGENLELSFRVWQCGGKLEIHPCSHVGHVFP-KRAPYARPN- 374
Cdd:cd02510 159 RESPTAPIRSPTMAGGLFAIDREWFLELGGYDEGMDIWGGENLELSFKVWQCGGSIEIVPCSRVGHIFRrKRKPYTFPGg 238

                       250       260       270       280       290       300
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 7657112  375 ---FLQNTARAAEVWMDEYKEHFYNRNPPARKEAYGDLSERKLLRERLKCKSFDWYLKNVF 432
Cdd:cd02510 239 sgtVLRNYKRVAEVWMDEYKEYFYKARPELRNIDYGDLSERKALRERLKCKSFKWYLENVY 299

pp-GalNAc-T initiates the formation of mucin-type O-linked glycans; UDP-GalNAc: polypeptide alpha-N-acetylgalactosaminyltransferases (pp-GalNAc-T) initiate the formation of mucin-type, O-linked glycans by catalyzing the transfer of alpha-N-acetylgalactosamine (GalNAc) from UDP-GalNAc to hydroxyl groups of Ser or Thr residues of core proteins to form the Tn antigen (GalNAc-a-1-O-Ser/Thr). These enzymes are type II membrane proteins with a GT-A type catalytic domain and a lectin domain located on the lumen side of the Golgi apparatus. In human, there are 15 isozymes of pp-GalNAc-Ts, representing the largest of all glycosyltransferase families. Each isozyme has unique but partially redundant substrate specificity for glycosylation sites on acceptor proteins.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  138 SVIIAFYNEAWSTLLRTIHSVLETSPAVLLKEIILVDDLSDRIYLKAQLETYISN-LERVRLIRTNKREGLVRARLIGAT 216
Cdd:cd02510   1 SVIIIFHNEALSTLLRTVHSVINRTPPELLKEIILVDDFSDKPELKLLLEEYYKKyLPKVKVLRLKKREGLIRARIAGAR 80

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  217 FATGDVLTFLDCHCECNTGWLEPLLERISRDETAIVCPVIDTIDWNTFEfYMQTGEPMIGGFDWRLTFQWHSVPKHERdR 296
Cdd:cd02510  81 AATGDVLVFLDSHCEVNVGWLEPLLARIAENRKTVVCPIIDVIDADTFE-YRGSSGDARGGFDWSLHFKWLPLPEEER-R 158

                       170       180       190       200       210       220       230       240
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  297 RTSRIDPIRSPTMAGGLFAVSKKYFQYLGTYDTGMEVWGGENLELSFRVWQCGGKLEIHPCSHVGHVFP-KRAPYARPN- 374
Cdd:cd02510 159 RESPTAPIRSPTMAGGLFAIDREWFLELGGYDEGMDIWGGENLELSFKVWQCGGSIEIVPCSRVGHIFRrKRKPYTFPGg 238

                       250       260       270       280       290       300
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 7657112  375 ---FLQNTARAAEVWMDEYKEHFYNRNPPARKEAYGDLSERKLLRERLKCKSFDWYLKNVF 432
Cdd:cd02510 239 sgtVLRNYKRVAEVWMDEYKEYFYKARPELRNIDYGDLSERKALRERLKCKSFKWYLENVY 299

Glycosyl transferase family 2; Diverse family, transferring sugar from UDP-glucose, UDP-N-acetyl- galactosamine, GDP-mannose or CDP-abequose, to a range of substrates including cellulose, dolichol phosphate and teichoic acids.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112    138 SVIIAFYNEaWSTLLRTIHSVLETSPavLLKEIILVDDLSdRIYLKAQLETYISNLERVRLIRTNKREGLVRARLIGATF 217
Cdd:pfam00535   1 SVIIPTYNE-EKYLLETLESLLNQTY--PNFEIIVVDDGS-TDGTVEIAEEYAKKDPRVRVIRLPENRGKAGARNAGLRA 76

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112    218 ATGDVLTFLDCHCECNTGWLEPLLERISRDETAIVCPVIDTIDWNTFEFYmqtgepmiggfdWRLTFQWHSVPKHERDRR 297
Cdd:pfam00535  77 ATGDYIAFLDADDEVPPDWLEKLVEALEEDGADVVVGSRYVIFGETGEYR------------RASRITLSRLPFFLGLRL 144

                         170       180
                  ....*....|....*....|..
gi 7657112    298 TSRIDPIRSPTMAGGLFAVSKK 319
Cdd:pfam00535 145 LGLNLPFLIGGFALYRREALEE 166

Ricin-type beta-trefoil; Carbohydrate-binding domain formed from presumed gene triplication.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112     457 CLDYNAPDNNptganLSLFGCHGQGGNQFFEYTSNKEIRFNSvTELCAEVPQQK-DYVGMQNCPKDGLpvpvNIIWHFKE 535
Cdd:smart00458   9 CLDVNGNKNP-----VGLFDCHGTGGNQLWKLTSDGAIRIKD-TDLCLTANGNTgSTVTLYSCDGTND----NQYWEVNK 78

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|..
gi 7657112     536 DGTIFHPHTRLCLSAYRTAEGRPsVHMKTCDaLDKNQLWRFE 577
Cdd:smart00458  79 DGTIRNPDSGKCLDVKDGNTGTK-VILWTCS-GNPNQKWIFE 118

transferase 2, rSAM/selenodomain-associated; This enzyme may transfer a nucleotide, or it sugar moiety, as part of a biosynthetic pathway. Other proposed members of the pathway include another transferase (TIGR04282), a phosphoesterase, and a radical SAM enzyme (TIGR04167) whose C-terminal domain (pfam12345) frequently contains a selenocysteine. [Unknown function, Enzymes of unknown specificity]

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112    138 SVIIAFYNEA--WSTLLRTIHSVLETSpavllkEIILVDDLS-DRIYLKAQletyisnLERVRLIRTNKreGlvRARLI- 213
Cdd:TIGR04283   2 SIIIPVLNEAatLPELLADLQALRGDA------EVIVVDGGStDGTVEIAR-------SLGAKVIHSPK--G--RARQMn 64

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|
gi 7657112    214 -GATFATGDVLTFLdcHCEC--NTGWLEPLLERISRDETA 250
Cdd:TIGR04283  65 aGAALAKGDILLFL--HADTrlPKDFLEAIRRALAKPGYV 102

putative glycosyl transferase; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112   133 SLPTTSVIIAFYN--EAWSTLLRTIHSVLETSpavllKEIILVDDLS-DRIylKAQLETYISNLERVRLIrTNKREGLVR 209
Cdd:PRK10073   4 STPKLSIIIPLYNagKDFRAFMESLIAQTWTA-----LEIIIVNDGStDNS--VEIAKHYAENYPHVRLL-HQANAGVSV 75

                         90
                 ....*....|....*...
gi 7657112   210 ARLIGATFATGDVLTFLD 227
Cdd:PRK10073  76 ARNTGLAVATGKYVAFPD 93

pp-GalNAc-T initiates the formation of mucin-type O-linked glycans; UDP-GalNAc: polypeptide alpha-N-acetylgalactosaminyltransferases (pp-GalNAc-T) initiate the formation of mucin-type, O-linked glycans by catalyzing the transfer of alpha-N-acetylgalactosamine (GalNAc) from UDP-GalNAc to hydroxyl groups of Ser or Thr residues of core proteins to form the Tn antigen (GalNAc-a-1-O-Ser/Thr). These enzymes are type II membrane proteins with a GT-A type catalytic domain and a lectin domain located on the lumen side of the Golgi apparatus. In human, there are 15 isozymes of pp-GalNAc-Ts, representing the largest of all glycosyltransferase families. Each isozyme has unique but partially redundant substrate specificity for glycosylation sites on acceptor proteins.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  138 SVIIAFYNEAWSTLLRTIHSVLETSPAVLLKEIILVDDLSDRIYLKAQLETYISN-LERVRLIRTNKREGLVRARLIGAT 216
Cdd:cd02510   1 SVIIIFHNEALSTLLRTVHSVINRTPPELLKEIILVDDFSDKPELKLLLEEYYKKyLPKVKVLRLKKREGLIRARIAGAR 80

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  217 FATGDVLTFLDCHCECNTGWLEPLLERISRDETAIVCPVIDTIDWNTFEfYMQTGEPMIGGFDWRLTFQWHSVPKHERdR 296
Cdd:cd02510  81 AATGDVLVFLDSHCEVNVGWLEPLLARIAENRKTVVCPIIDVIDADTFE-YRGSSGDARGGFDWSLHFKWLPLPEEER-R 158

                       170       180       190       200       210       220       230       240
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  297 RTSRIDPIRSPTMAGGLFAVSKKYFQYLGTYDTGMEVWGGENLELSFRVWQCGGKLEIHPCSHVGHVFP-KRAPYARPN- 374
Cdd:cd02510 159 RESPTAPIRSPTMAGGLFAIDREWFLELGGYDEGMDIWGGENLELSFKVWQCGGSIEIVPCSRVGHIFRrKRKPYTFPGg 238

                       250       260       270       280       290       300
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 7657112  375 ---FLQNTARAAEVWMDEYKEHFYNRNPPARKEAYGDLSERKLLRERLKCKSFDWYLKNVF 432
Cdd:cd02510 239 sgtVLRNYKRVAEVWMDEYKEYFYKARPELRNIDYGDLSERKALRERLKCKSFKWYLENVY 299

ricin B-type lectin domain, beta-trefoil fold, found in the polypeptide N-acetylgalactosaminyltransferase 3 (GALNT3)-like subfamily; The GALNT3-like subfamily includes GALNT3, GALNT4, GALNT6 and GALNT12. They act as GalNAc transferases (EC 2.4.1.41) that catalyze the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. GALNT3 has activity toward HIV envelope glycoprotein gp120, EA2, Muc2 and Muc5. It probably glycosylates fibronectin in vivo as well as FGF23. It plays a central role in phosphate homeostasis. GALNT4 shows highest activity towards Muc7, EA2 and Muc2, with a lower activity compared to GALNT2. It glycosylates 'Thr-57' of SELPLG. GALNT6 may participate in the synthesis of oncofetal fibronectin. It has activity toward Muc1a, Muc2, EA2 and fibronectin peptides. GALNT12 has activity toward non-glycosylated peptides such as Muc5AC, Muc1a and EA2, and no detectable activity with non-glycosylated Muc2 and Muc7. It displays enzymatic activity toward the Gal-NAc-Muc5AC glycopeptide, but no detectable activity to mono-GalNAc-glycosylated Muc1a, Muc2, Muc7 and EA2. It may play an important role in the initial step of mucin-type oligosaccharide biosynthesis in digestive organs. Members of this family comprise a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which are characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  442 PGWHGAIRSMGiSSECLDYNaPDNNPTGANLSLFGCHGQGGNQFFEYTSNKEIRFNSVTELCAEVpQQKDYVGMQNCPKD 521
Cdd:cd23435   1 PGYYGALRNKG-SELCLDVN-NPNGQGGKPVIMYGCHGLGGNQYFEYTSKGEIRHNIGKELCLHA-SGSDEVILQHCTSK 77

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 7657112  522 GLPVPVNIIWHFKEDGTIFHPHTRLCLSAYrtaegRPSVHMKTCDALDKNQLWRFE 577
Cdd:cd23435  78 GKDVPPEQKWLFTQDGTIRNPASGLCLHAS-----GYKVLLRTCNPSDDSQKWTFI 128

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 12 (GALNT12) and similar proteins; GALNT12 (EC 2.4.1.41), also called polypeptide GalNAc transferase 12, GalNAc-T12, pp-GaNTase 12, protein-UDP acetylgalactosaminyltransferase 12, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 12, catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. GALNT12 has activity toward non-glycosylated peptides such as Muc5AC, Muc1a and EA2, and no detectable activity with non-glycosylated Muc2 and Muc7. It displays enzymatic activity toward the Gal-NAc-Muc5AC glycopeptide, but no detectable activity to mono-GalNAc-glycosylated Muc1a, Muc2, Muc7 and EA2. It may play an important role in the initial step of mucin-type oligosaccharide biosynthesis in digestive organs. GALNT12 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  442 PGWHGAIRSMGISSECLDYNAPD-NNPTGANLSLFGCHGQGGNQFFEYTSNKEIRFNSVT-ELCAEVPQQKDYVGMQNCP 519
Cdd:cd23471   1 PGFFGMLKNKGMTNYCFDYNPPDeHQIAGHQVILYQCHGMGQNQFFEYTSQNEIRYNTRQpEGCAAVDAGTDFLTMHLCR 80

                        90       100       110       120       130       140
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  520 KDGLPVPVNIIWHFKEDGTIFHPHTRLCLSAYR-TAEGRPSVHMKTCDALDkNQLWRFEK 578
Cdd:cd23471  81 ENRQAVPENQKFIFREDGSLFHVQTQKCVQAVRnESSGSPAPVLRPCTDSD-HQKWFFKE 139

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 7 (GALNT7) and similar proteins; GALNT7 (EC 2.4.1.41), also called polypeptide GalNAc transferase 7, GalNAc-T7, pp-GaNTase 7, protein-UDP acetylgalactosaminyltransferase 7, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 7, acts as glycopeptide transferase involved in O-linked oligosaccharide biosynthesis, which catalyzes the transfer of an N-acetyl-D-galactosamine residue to an already glycosylated peptide. In contrast to other proteins of the family, it does not act as a peptide transferase that transfers GalNAc onto serine or threonine residue on the protein receptor, but instead requires the prior addition of a GalNAc on a peptide before adding additional GalNAc moieties. Its appropriate peptide substrate remains unidentified. GALNT7 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  443 GWhGAIRSMGiSSECLDYNapdNNPTGANLSLFGCHGQGGNQFFEYTSNKEIRFNsvtELCAEVPQQKDYVGMQNCPKdg 522
Cdd:cd23437   4 AW-GEIRNLG-TGLCLDTM---GHQNGGPVGLYPCHGMGGNQLFRLNEAGQLAVG---EQCLTASGSGGKVKLRKCNL-- 73

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|....*
gi 7657112  523 lpvPVNIIW-HFKEDGTIFHPHTRLCLSayRTAEGRPsVHMKTCDALDKNQLWRF 576
Cdd:cd23437  74 ---GETGKWeYDEATGQIRHKGTGKCLD--LNEGTNK-LILQPCDSSSPSQKWEF 122

ricin B-type lectin domain, beta-trefoil fold, found in Drosophila melanogaster polypeptide N-acetylgalactosaminyltransferase 9 (Pgant9) and similar proteins; The subfamily includes Pgant9 (also called pp-GaNTase 9, protein-UDP acetylgalactosaminyltransferase 9, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 9), Pgant4 (also called pp-GaNTase 4, N-acetylgalactosaminyltransferase 4, protein-UDP acetylgalactosaminyltransferase 4, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 4) and Pgant6 (also called pp-GaNTase 6, N-acetylgalactosaminyltransferase 6, protein-UDP acetylgalactosaminyltransferase 6, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 6). They function as GalNAc transferases (EC 2.4.1.41) that catalyze the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. Pgant9 can both act as a peptide transferase that transfers GalNAc onto unmodified peptide substrates, and as a glycopeptide transferase that requires the prior addition of a GalNAc on a peptide before adding additional GalNAc moieties. Pgant4 and Pgant6 do not act as a peptide transferase, but instead requires the prior addition of a GalNAc on a peptide before adding additional GalNAc moieties. They prefer the diglycosylated Muc5AC-3/13 as a substrate. Pgant6 may have a role in protein O-glycosylation in the Golgi and thereby in establishing and/or maintaining a proper secretory apparatus structure. Members of this subfamily contain a ricin B-type lectin domain at the C-terminus. The ricin B-type lectin domain shows a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. Each subdomain bears a potential sugar binding site.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  445 HGAIRSMGiSSECLDyNAPDNNPTGANLSLFGCHGQGGNQFFEYTSNKEIRFNsvtELCAEVPQQKDYVGMQNCPKDGlp 524
Cdd:cd23462   5 YGEIRNLA-GKLCLD-APGRKKELNKPVGLYPCHGQGGNQYWMLTKDGEIRRD---DLCLDYAGGSGDVTLYPCHGMK-- 77

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|....
gi 7657112  525 vpVNIIW-HFKEDGTIFHPHTRLCLSAyrtAEGRPSVHMKTCDALDKNQLWRFE 577
Cdd:cd23462  78 --GNQFWiYDEETKQIVHGTSKKCLEL---SDDSSKLVMEPCNGSSPRQQWEFE 126

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 6 (GALNT6) and similar proteins; GALNT6 (EC 2.4.1.41), also called polypeptide GalNAc transferase 6, GalNAc-T6, pp-GaNTase 6, protein-UDP acetylgalactosaminyltransferase 6, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 6, catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. GALNT6 may participate in the synthesis of oncofetal fibronectin. It has activity toward Muc1a, Muc2, EA2 and fibronectin peptides. GALNT6 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  442 PGWHGAIRSMGiSSECLDYNapDNNPTGANLSLFGCHGQGGNQFFEYTSNKEIRFNSVTELCAEVpqQKDYVGMQNCPKD 521
Cdd:cd23470   1 PTFYGAIKNEG-TNQCLDVG--ENNRGGKPLIMYSCHGMGGNQYFEYTTHKELRHNIAKQLCLRV--SKGPVQLGECHYK 75

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 7657112  522 GLP--VPVNIIWHFKEDGTIFHPHTRLCLSAYRTaegRPSvhMKTCDALDKNQLWRF 576
Cdd:cd23470  76 GKNsqVPPDEEWELTQDHLIRNSGSNMCLTARGK---HPA--MAPCNPADPHQLWSF 127

ricin B-type lectin domain, beta-trefoil fold, found in Drosophila melanogaster polypeptide N-acetylgalactosaminyltransferase 3 (Pgant3) and similar proteins; Pgant3, also called pp-GaNTase 3, protein-UDP acetylgalactosaminyltransferase 3, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 3, functions as a GalNAc transferase (EC 2.4.1.41) that catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. Pgant3 can both act as a peptide transferase that transfers GalNAc onto unmodified peptide substrates, and as a glycopeptide transferase that requires the prior addition of a GalNAc on a peptide before adding additional GalNAc moieties. It prefers EA2 as a substrate and has weak activity toward Muc5AC-3, -13 and -3/13 substrates. Pgant3 plays a critical role in the regulation of integrin-mediated cell adhesion during wing development by influencing, via glycosylation, the secretion and localization of the integrin ligand Tig to the basal cell layer interface. It may have a role in protein O-glycosylation in the Golgi and thereby in establishing and/or maintaining a proper secretory apparatus structure. Together with Pgant35A, Pgant3 regulates integrin levels and activity-dependent integrin signaling at the synapse in neurons and muscles. Members of this subfamily contain a ricin B-type lectin domain at the C-terminus. The ricin B-type lectin domain shows a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. Each subdomain bears a potential sugar binding site.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  446 GAIRSMGiSSECLDYNAPDNNptGANLSLFGCHGQGGNQFFEYTSNKEIRFNsvtELCAEVPQQKDyVGMQNCPkDGLPV 525
Cdd:cd23460   3 GQIKHTE-SGLCLDWAGESNG--DKTVALKPCHGGGGNQFWMYTGDGQIRQD---HLCLTADEGNK-VTLRECA-DQLPS 74

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|..
gi 7657112  526 PvniIWHFKE-DGTIFHPHTRLCLSayrTAEGRPSVHMKTCDALDKNQLWRF 576
Cdd:cd23460  75 Q---EWSYDEkTGTIRHRSTGLCLT---LDANNDVVILKECDSNSLWQKWIF 120

Glycosyltransferase, catalytic subunit of cellulose synthase and poly-beta-1,6-N-acetylglucosamine synthase [Cell motility];

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  126 AKKFHYRSLPTTSVIIAFYNEAwSTLLRTIHSVLETSPAVLLKEIILVDDLS-DRiyLKAQLETYISNLERVRLIRTNKR 204
Cdd:COG1215  20 RRRRAPADLPRVSVIIPAYNEE-AVIEETLRSLLAQDYPKEKLEVIVVDDGStDE--TAEIARELAAEYPRVRVIERPEN 96

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*...
gi 7657112  205 EGLVRARLIGATFATGDVLTFLDCHCECNTGWLEPLLERISRDETAIV 252
Cdd:COG1215  97 GGKAAALNAGLKAARGDIVVFLDADTVLDPDWLRRLVAAFADPGVGAS 144

Glycosyltransferase family A (GT-A) includes diverse families of glycosyl transferases with a common GT-A type structural fold; Glycosyltransferases (GTs) are enzymes that synthesize oligosaccharides, polysaccharides, and glycoconjugates by transferring the sugar moiety from an activated nucleotide-sugar donor to an acceptor molecule, which may be a growing oligosaccharide, a lipid, or a protein. Based on the stereochemistry of the donor and acceptor molecules, GTs are classified as either retaining or inverting enzymes. To date, all GT structures adopt one of two possible folds, termed GT-A fold and GT-B fold. This hierarchy includes diverse families of glycosyl transferases with a common GT-A type structural fold, which has two tightly associated beta/alpha/beta domains that tend to form a continuous central sheet of at least eight beta-strands. The majority of the proteins in this superfamily are Glycosyltransferase family 2 (GT-2) proteins. But it also includes families GT-43, GT-6, GT-8, GT13 and GT-7; which are evolutionarily related to GT-2 and share structure similarities.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  139 VIIAFYNEAwSTLLRTIHSVLE-TSPAVllkEIILVDDLS-DRIYLKAqlETYISNLERVRLIRTNKREGLVRARLIGAT 216
Cdd:cd00761   1 VIIPAYNEE-PYLERCLESLLAqTYPNF---EVIVVDDGStDGTLEIL--EEYAKKDPRVIRVINEENQGLAAARNAGLK 74

                        90       100       110
                ....*....|....*....|....*....|....*..
gi 7657112  217 FATGDVLTFLDCHCECNTGWLEPLLERISRDETAIVC 253
Cdd:cd00761  75 AARGEYILFLDADDLLLPDWLERLVAELLADPEADAV 111

Glycosyltransferase, GT2 family [Carbohydrate transport and metabolism];

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  135 PTTSVIIAFYNEaWSTLLRTIHSVLETSPAVLlkEIILVDDLSD---RIYLKAQletyisNLERVRLIRTNKREGLVRAR 211
Cdd:COG1216   3 PKVSVVIPTYNR-PELLRRCLESLLAQTYPPF--EVIVVDNGSTdgtAELLAAL------AFPRVRVIRNPENLGFAAAR 73

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
gi 7657112  212 LIGATFATGDVLTFLDCHCECNTGWLEPLLER----ISRD 247
Cdd:COG1216  74 NLGLRAAGGDYLLFLDDDTVVEPDWLERLLAAacllIRRE 113

ricin B-type lectin domain, beta-trefoil fold, found in Streptomyces olivaceoviridis endo-1,4-beta-xylanase and similar proteins; The family includes Streptomyces olivaceoviridis endo-1,4-beta-xylanase (XLN, EC 3.2.1.8), Streptomyces avermitilis beta-L-arabinopyranosidase (EC 3.2.1.185), and Streptomyces coelicolor extracellular exo-alpha-L-arabinofuranosidase (ABF, EC 3.2.1.55). XLN, also called xylanase, or 1,4-beta-D-xylan xylanohydrolase, belongs to the glycosyl hydrolase 10 (cellulase F) family. It contributes to hydrolyze hemicellulose, the major component of plant cell walls. XLN contains a (beta/alpha)8-barrel as a catalytic domain, a family 13 carbohydrate binding module (CBM13) as a xylan binding domain (XBD) and a Gly/Pro-rich linker between them. Beta-L-arabinopyranosidase belongs to the glycosyl hydrolase 27 (GH27) family. It has a GH27 catalytic domain, an antiparallel beta-domain containing Greek key motifs, another antiparallel beta-domain forming a jellyroll structure, and a CBM13 module. ScAraf62A, also called ABF, or arabinosidase, or arabinoxylan arabinofuranohydrolase, belongs to the glycosyl hydrolase 62 (GH62) family. It is involved in the degradation of xylan and is a key enzyme in the complete degradation of the plant cell wall. It has a specific arabinofuranose-debranching activity on xylan from gramineae. It acts synergistically with xylanases and binds specifically to xylan. ScAraf62A comprises a CBM13 module at its N-terminus and a catalytic domain at its C-terminus. This model corresponds to the CBM13 module, which is a ricin B-type lectin domain with a beta-trefoil fold, characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. Each subdomain may contain a potential sugar-binding pocket.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  446 GAIRSMGiSSECLDynAPDNNPT-GANLSLFGCHGqGGNQFFEYTSNKEIRFNsvTELCAEVPQQKDYVG----MQNCPK 520
Cdd:cd23418   6 GQIRGYG-SGRCLD--VPGGSTTnGTRLILWDCHG-GANQQFTFTSAGELRVG--GDKCLDAAGGGTTNGtpvvIWPCNG 79

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|....*...
gi 7657112  521 DGlpvpvNIIWHFKEDGTIFHPHTRLCLSAYR--TAEGRPsVHMKTCDALDkNQLWRF 576
Cdd:cd23418  80 GA-----NQKWRFNSDGTIRNVNSGLCLDVAGggTANGTR-LILWSCNGGS-NQRWRR 130

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 1 (GALNT1) and similar proteins; GALNT1 (EC 2.4.1.41), also called polypeptide GalNAc transferase 1, GalNAc-T1, pp-GaNTase 1, protein-UDP acetylgalactosaminyltransferase 1, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 1, catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. It has a broad spectrum of substrates for peptides such as EA2, Muc5AC, Muc1a, Muc1b and Muc7. GALNT1 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain is required in the glycopeptide specificity of enzyme activity but not for activity with naked peptide substrates, suggesting that it triggers the catalytic domain to act on GalNAc-glycopeptide substrates.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  446 GAIRSMGiSSECLDYNAPDNNptgANLSLFGCHGQGGNQFFEYTSNKEIRFNsvtELCAEVPQQKDYVGMQNCPKdglpV 525
Cdd:cd23466   7 GEIRNVE-TNQCLDNMARKEN---EKVGIFNCHGMGGNQVFSYTANKEIRTD---DLCLDVSKLNGPVMMLKCHH----L 75

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|.
gi 7657112  526 PVNIIWHFKE-DGTIFHPHTRLCL-SAYRTAEGRPSvhMKTCDAlDKNQLW 574
Cdd:cd23466  76 KGNQLWEYDPvKLTLLHVNSNQCLdKATEEDSQVPS--IRDCNG-SRSQQW 123

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 13 (GALNT13) and similar proteins; GALNT13 (EC 2.4.1.41), also called polypeptide GalNAc transferase 13, GalNAc-T13, pp-GaNTase 13, protein-UDP acetylgalactosaminyltransferase 13, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 13, catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. It has a much stronger activity than GALNT1 to transfer GalNAc to mucin peptides, such as Muc5Ac and Muc7. It can glycosylate SDC3. It may be responsible for the synthesis of Tn antigen in neuronal cells. GALNT13 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). The model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  446 GAIRSMGiSSECLDYNAPDNNptgANLSLFGCHGQGGNQFFEYTSNKEIRFNsvtELCAEVPQQKDYVGMQNCPKdglpV 525
Cdd:cd23467   7 GEIRNVE-TNQCLDNMGRKEN---EKVGIFNCHGMGGNQVFSYTADKEIRTD---DLCLDVSRLNGPVVMLKCHH----M 75

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|
gi 7657112  526 PVNIIWHFK-EDGTIFHPHTRLCLSAyRTAEGRPSVHMKTCDAlDKNQLW 574
Cdd:cd23467  76 RGNQLWEYDaERLTLRHVNSNQCLDE-PSEEDKMVPTMKDCSG-SRSQQW 123

DPM_DPG-synthase_like is a member of the Glycosyltransferase 2 superfamily; DPM1 is the catalytic subunit of eukaryotic dolichol-phosphate mannose (DPM) synthase. DPM synthase is required for synthesis of the glycosylphosphatidylinositol (GPI) anchor, N-glycan precursor, protein O-mannose, and C-mannose. In higher eukaryotes,the enzyme has three subunits, DPM1, DPM2 and DPM3. DPM is synthesized from dolichol phosphate and GDP-Man on the cytosolic surface of the ER membrane by DPM synthase and then is flipped onto the luminal side and used as a donor substrate. In lower eukaryotes, such as Saccharomyces cerevisiae and Trypanosoma brucei, DPM synthase consists of a single component (Dpm1p and TbDpm1, respectively) that possesses one predicted transmembrane region near the C terminus for anchoring to the ER membrane. In contrast, the Dpm1 homologues of higher eukaryotes, namely fission yeast, fungi, and animals, have no transmembrane region, suggesting the existence of adapter molecules for membrane anchoring. This family also includes bacteria and archaea DPM1_like enzymes. However, the enzyme structure and mechanism of function are not well understood. The UDP-glucose:dolichyl-phosphate glucosyltransferase (DPG_synthase) is a transmembrane-bound enzyme of the endoplasmic reticulum involved in protein N-linked glycosylation. This enzyme catalyzes the transfer of glucose from UDP-glucose to dolichyl phosphate. This protein family belongs to Glycosyltransferase 2 superfamily.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  139 VIIAFYNEAwSTLLRTIHSVLETSPAVLLKEIILVDDLS-DRIYlkAQLETYISNLERVRLIRTNKREGLVRARLIGATF 217
Cdd:cd04179   1 VVIPAYNEE-ENIPELVERLLAVLEEGYDYEIIVVDDGStDGTA--EIARELAARVPRVRVIRLSRNFGKGAAVRAGFKA 77

                        90       100       110
                ....*....|....*....|....*....|....*.
gi 7657112  218 ATGDVLTFLDCHCECNTGWLEPLLERISRDETAIVC 253
Cdd:cd04179  78 ARGDIVVTMDADLQHPPEDIPKLLEKLLEGGADVVI 113

first ricin B-type lectin domain, beta-trefoil fold, found in type II ribosome-inactivating proteins (RIPs); Type II ribosome-inactivating proteins (RIPs) inhibit translation in eukaryotes by irreversibly inactivating the 28S rRNA and preventing the binding of elongation factor II to the ribosome. They consist of a catalytic A-chain which has rRNA N-glycosidase activity and a lectin B-chain containing two ricin B-type lectin domains with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The lectin chain facilitates the internalization of the catalytic chain on binding to the cell surface. The two chains are connected by a disulfide bridge. This model corresponds to the first ricin B-type lectin domain. Members of this subfamily includes Ricinus communis ricin, bitter gourd (Momordica charantia) seed lectin (BGSL), snake gourd (Trichosanthes anguina) seed lectin (SGSL), Sambucus ebulus ebulin I, Sambucus nigra nigrin b (also known as agglutinin V or SNAV), SNAI (also known as agglutinin I), SNAI' and SNAIf, Abrus precatorius abrin (ABR) and agglutinin-I (AAG), and Viscum album beta-galactoside-specific lectins 1-4 (also known as mistletoe lectins or MLs).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  457 CLDYNaPDNNPTGANLSLFGCHGQGGNQFFEYTSNKEIRFNSVTeLCAEVPQQKDYVGMQNCPKdglPVPVNIIWHFKED 536
Cdd:cd23443  12 CVDVK-DGYYSDGNPVILWPCKSQDANQLWTFKRDGTIRSNGKC-LTTNGYSPGSYVVIYDCST---AVAEATKWEVSDD 86

                        90       100
                ....*....|....*....|.
gi 7657112  537 GTIFHPHTRLCLSAYRTAEGR 557
Cdd:cd23443  87 GTIINPASGLVLTADSGTSGT 107

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 11 (GALNT11) and similar proteins; GALNT11 (EC 2.4.1.41), also called polypeptide GalNAc transferase 11, GalNAc-T11, pp-GaNTase 11, protein-UDP acetylgalactosaminyltransferase 11, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 11, catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. It is involved in left/right asymmetry by mediating O-glycosylation of NOTCH1. O-glycosylation of NOTCH1 promotes its activation, modulating the balance between motile and immotile (sensory) cilia at the left-right organizer (LRO). GALNT11 displays the same enzyme activity toward MUC1, MUC4, and EA2 as GALNT1. It is not involved in glycosylation of erythropoietin (EPO). GALNT11 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  445 HGAIRSMGiSSECLDynAPDNNPT-GANLSLFGCHGQGGNQFFEYTSNKEIRFNSVteLCAEVP-QQKDYVGMQNCPKDG 522
Cdd:cd23440   5 KGQLKHAG-SGLCLV--AEDEVSQkGSLLVLRPCSRNDKKQLWYYTEDGELRLANL--LCLDSSeTSSDFPRLMKCHGSG 79

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|....
gi 7657112  523 LpvpvNIIWHFKEDGTIFHPHTRLCLSAYRTAEGrPSVHMKTCDaLDKNQLWRF 576
Cdd:cd23440  80 G----SQQWRFKKDNRLYNPASGQCLAASKNGTS-GYVTMDICS-DSPSQKWVF 127

Myxococcus xanthus RfbC like proteins are required for O-antigen biosynthesis; The rfbC gene encodes a predicted protein of 1,276 amino acids, which is required for O-antigen biosynthesis in Myxococcus xanthus. It is a subfamily of Glycosyltransferase Family GT2, which includes diverse families of glycosyl transferases with a common GT-A type structural fold, which has two tightly associated beta/alpha/beta domains that tend to form a continuous central sheet of at least eight beta-strands. These are enzymes that catalyze the transfer of sugar moieties from activated donor molecules to specific acceptor molecules, forming glycosidic bonds.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  135 PTTSVIIAFYNEAWSTLLRTIHSVLETSPAVLlkEIILVDDLSDRIYLKAQLETYISNLERVRLIRTNKREGLVRARLIG 214
Cdd:cd04184   1 PLISIVMPVYNTPEKYLREAIESVRAQTYPNW--ELCIADDASTDPEVKRVLKKYAAQDPRIKVVFREENGGISAATNSA 78

                        90
                ....*....|....
gi 7657112  215 ATFATGDVLTFLDC 228
Cdd:cd04184  79 LELATGEFVALLDH 92

ricin B-type lectin domain, beta-trefoil fold, found in the macrophage mannose receptor (MRC) family; The MRC family includes MRC1-2, receptor-type tyrosine-protein phosphatase beta (PTPRB) isoform e, secretory phospholipase A2 receptor (PLA2R1), and lymphocyte antigen 75 (Ly-75). MRC1 mediates the endocytosis of glycoproteins by macrophages. It binds both sulfated and non-sulfated polysaccharide chains, and acts as a phagocytic receptor for bacteria, fungi, and other pathogens. It also acts as a receptor for Dengue virus envelope protein E. MRC2 may play a role as an endocytotic lectin receptor displaying calcium-dependent lectin activity. It internalizes glycosylated ligands from the extracellular space for release in an endosomal compartment via clathrin-mediated endocytosis. It may be involved in plasminogen activation system controlling the extracellular level of PLAUR/PLAU, and thus may regulate protease activity at the cell surface. It may contribute to cellular uptake, remodeling, and degradation of extracellular collagen matrices. It may play a role during cancer progression as well as in other chronic tissue destructive diseases acting on collagen turnover. It may participate in remodeling of extracellular matrix cooperating with the matrix metalloproteinases (MMPs). PTPRB (EC 3.1.3.48), also called protein-tyrosine phosphatase beta, plays an important role in blood vessel remodeling and angiogenesis. It is not necessary for the initial formation of the blood vessels but is essential for their maintenance and remodeling. It is also essential for the maintenance of endothelial cell contact integrity and for the adhesive function of VE-cadherin in endothelial cells that requires the presence of plakoglobin. PLA2R1 is a receptor for secretory phospholipase A2 (sPLA2). It acts as a receptor for phospholipase sPLA2-IB/PLA2G1B but not sPLA2-IIA/PLA2G2A. It can also bind to snake PA2-like toxins. It may be involved in responses in proinflammatory cytokine productions during endotoxic shock. It also has endocytic properties and rapidly internalizes sPLA2 ligands, which is particularly important for the clearance of extracellular sPLA2s to protect their potent enzymatic activities. Ly-75 acts as an endocytic receptor to direct captured antigens from the extracellular space to a specialized antigen-processing compartment. It causes reduced proliferation of B-lymphocytes. All family members contain a ricin B-type lectin domain at the N-terminus. The ricin B-type lectin domain shows a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. Each subdomain may harbor a sugar-binding pocket. One member of this family, MRC1, is missing the gamma subdomain.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 7657112  496 FNSVTELCAEVPQQKDYVGMQNCpkdgLPVPVNIIWHFKEDGTIFHPHTRLCLSAYRTAEGRPsVHMKTCDALDKNQLWR 575
Cdd:cd23385   6 YNEDLGKCLAARSSSSKVSLSTC----NPNSPNQQWKWTSGHRLFNVGTGKCLGVSSSSPSSP-LRLFECDSEDELQKWK 80