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Conserved domains on  [gi|496136230|ref|WP_008860737|]
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MULTISPECIES: RagB/SusD family nutrient uptake outer membrane protein [Barnesiella]

Protein Classification

RagB/SusD family nutrient uptake outer membrane protein( domain architecture ID 230101)

RagB/SusD family nutrient uptake outer membrane protein similar to Bacteroides thetaiotaomicron starch-binding protein SusD, which is a major starch-binding protein present at the surface of the cell and mediates starch-binding before starch transport in the periplasm for degradation

CATH:  1.20.120.840
Gene Ontology:  GO:0009279|GO:0016020|GO:2001070
PubMed:  18611370
SCOP:  4001583

Graphical summary

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List of domain hits

Name Accession Description Interval E-value
SusD_RagB super family cl19983
SusD family; This domain is found in bacterial cell surface proteins such SusD and SusD-like ...
251-508 1.27e-20

SusD family; This domain is found in bacterial cell surface proteins such SusD and SusD-like proteins as well RagB, outer membrane surface receptor antigen. Bacteroidetes, one of the two dominant bacterial phyla in the human gut, are Gram-negative saccharolytic microorganizms that utilize a diverse array of glycans. Hence, they express starch-utilization system (Sus) for glycan uptake. SusD has 551 amino acids, and is almost entirely alpha-helical, with 22 alpha-helices, eight of which form 4 tetra-trico peptide repeats (TPRs: helix-turn-helix motifs involved in protein-protein interactions). The four TPRs pack together to create a right-handed super-helix. This is predicted to mediate the formation of SusD and SusC porin complex at the cell surface. The interaction between SusC and TPR1/TPR2 region of SusD is predicted to be of functional importance since it allows SusD to be in position for oligosaccharide capture from other Sus lipoproteins and delivery of these glycans to the SusC porin. The non-TPR containing portion of SusD is where starch binding occurs. The binding site is a shallow surface cavity located on top of TPR1. SusD homologs such as SusD-like proteins have a critical role in carbohydrate acquisition. Both SusD and its homologs, contain 15-20 residues at the N-terminus that might be a flexible linker region, anchoring the protein to the membrane and the glycan-binding domain. Other homologs to SusD have been examined in Porphyromonas gingivalis such as RagB, an immunodominant outer-membrane surface receptor antigen. Structural characterization of RagB shows substantial similarity with Bacteroides thetaiotaomicron SusD (i.e alpha-helices and TPR regions). Based on this structural similarity, functional studies suggest that, RagB binding of glycans occurs at pockets on the molecular surface that are distinct from those of SusD.


The actual alignment was detected with superfamily member pfam07980:

Pssm-ID: 429768  Cd Length: 294  Bit Score: 92.17  E-value: 1.27e-20
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  251 SITEVMIKDGEYSLQKDYMSIWSPSNQRNSEVifpipnfPEGGLGNCFLAHALPADYVSQNGIALTKWGGFLVPWDFYDT 330
Cdd:pfam07980   3 SIFEVQYDSGVTGGGGRSYGVNLGPNGGAGGG-------EGGGWGGLGPTQDLVDLFYMADGSPIFDTDDDSDGTDTIEI 75
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  331 YDPKDKRRNALLATYWN----------GKKMVDRRTEYTGKPGAVPMKYQENP---------------STTGQWDASEYV 385
Cdd:pfam07980  76 DGNRDPRFYATVAFDGCtwnagsnnlvYVAGKYTDGNLGSGDTGAPNSDGNRSntgyllrkfvdedgdSSGGGGSSIDFP 155
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  386 INRYAEVILARAEALNEIyGPTQEAKDLVHEIRERAFDNYKGSKyekeinDITDKDAFRAHLLKERGWEFCWEGMRRPDL 465
Cdd:pfam07980 156 VIRYAEVLLNYAEALNEL-GGPEEAIKYINKIRERAGLPDLTDS------AYGSQEELIDAIRDERRIELAGEGHRFFDL 228
                         250       260       270       280       290       300
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 496136230  466 IRHGELI----------------------SNAIARGKLMAEPKHILYAIPQSVIYENPNLKNNEG 508
Cdd:pfam07980 229 RRWKKALqelnglfgggnayngsnkgldnFILERPDELEDNFKHYLLPIPQSEIDRNPGLTQNPG 293
SusD super family cl21747
starch binding outer membrane protein SusD; SusD-like proteins from Bacteroidetes, members of ...
37-469 1.73e-18

starch binding outer membrane protein SusD; SusD-like proteins from Bacteroidetes, members of the human distal gut microbiota, are part of the starch utilization system (Sus). Sus is one of the large clusters of glycosyl hydrolases, called polysaccharide utilization loci (PULs), which play an important role in polysaccharide recognition and uptake, and it is needed for growth on amylose, amylopectin, pullulan, and maltooligosaccharides. SusD, together with SusC, a predicted beta-barrel porin, forms the minimum outer-membrane starch-binding complex. The adult human distal gut microbiota is essential for digestion of a large variety of dietary polysaccharides, for which humans lack the necessary glycosyl hydrolases.


The actual alignment was detected with superfamily member cd08977:

Pssm-ID: 451378 [Multi-domain]  Cd Length: 359  Bit Score: 87.09  E-value: 1.73e-18
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  37 TENDVKAAVTGIYHELRGGGWDRYNCAW--GSLLTmqigctDECDCNWVWDKQLDFLWTAETTDLGQF---YTGLVPAVT 111
Cdd:cd08977    1 DPTDAEAALTGLYAGLRSSGNYYGGTLGllGDLRA------DD*VAASNSGDYTEVNTNNNPNDSAFGtssWNGVYTNIN 74
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 112 KATSLLERM-RKISISAPIKRRYMAEVRCLRAMWAYDLYDLYGTVPLITDPDIALDPqkaqsymPERPSIEWYVNFIDTE 190
Cdd:cd08977   75 NANIFLEKIdEASELTEANRNRYKGEAKFIRALAYFYLTRLFGGVPLSTAADQGTET-------PPRDSQEEVYTQILAD 147
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 191 LKEAEENLKPAS----LLAASEYGRMTKGIAQMYMLKLYMHEAGQERHYrndegkammwWNRVDSITEVMIKDGEYSLQK 266
Cdd:cd08977  148 LDEAIALLPEASsaqdFYIYFGDGRAWKKAARALLARVYLYLANYTAAD----------YAEALTAAEKSFKGGVTLLTN 217
                        250       260       270       280       290       300       310       320
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 267 DYmsIWSPSNqrNSEVIFPIPNFPEGGLGNCFLAHALPADyvsqngialtkWGGFLVPWDFYDTYD-PKDKRrnallaty 345
Cdd:cd08977  218 LF--GENAAN--SKEDIFEIYYADSGDNSNPLGSLNNNNG-----------YANFRVSADIIDKLDgYGDPR-------- 274
                        330       340       350       360       370       380       390       400
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 346 wngkkmvdrrteytgkpgavpmkyqenpsttgqWDASEYVINRYAEVILARAEALNEIyGPTQEAKDLVHEIRERAFDNy 425
Cdd:cd08977  275 ---------------------------------LSLAPIPIIRYAEVLLLRAEALARL-GNGADAIEYLNAVRRRSGGN- 319
                        410       420       430       440
                 ....*....|....*....|....*....|....*....|....
gi 496136230 426 kgskYEKEINDITDKDAFRAHLLKERGWEFCWEGMRRPDLIRHG 469
Cdd:cd08977  320 ----AANNTSQASTAEELLEEILDERRLELFGEGHRWYDLRRTG 359
 
Name Accession Description Interval E-value
SusD_RagB pfam07980
SusD family; This domain is found in bacterial cell surface proteins such SusD and SusD-like ...
251-508 1.27e-20

SusD family; This domain is found in bacterial cell surface proteins such SusD and SusD-like proteins as well RagB, outer membrane surface receptor antigen. Bacteroidetes, one of the two dominant bacterial phyla in the human gut, are Gram-negative saccharolytic microorganizms that utilize a diverse array of glycans. Hence, they express starch-utilization system (Sus) for glycan uptake. SusD has 551 amino acids, and is almost entirely alpha-helical, with 22 alpha-helices, eight of which form 4 tetra-trico peptide repeats (TPRs: helix-turn-helix motifs involved in protein-protein interactions). The four TPRs pack together to create a right-handed super-helix. This is predicted to mediate the formation of SusD and SusC porin complex at the cell surface. The interaction between SusC and TPR1/TPR2 region of SusD is predicted to be of functional importance since it allows SusD to be in position for oligosaccharide capture from other Sus lipoproteins and delivery of these glycans to the SusC porin. The non-TPR containing portion of SusD is where starch binding occurs. The binding site is a shallow surface cavity located on top of TPR1. SusD homologs such as SusD-like proteins have a critical role in carbohydrate acquisition. Both SusD and its homologs, contain 15-20 residues at the N-terminus that might be a flexible linker region, anchoring the protein to the membrane and the glycan-binding domain. Other homologs to SusD have been examined in Porphyromonas gingivalis such as RagB, an immunodominant outer-membrane surface receptor antigen. Structural characterization of RagB shows substantial similarity with Bacteroides thetaiotaomicron SusD (i.e alpha-helices and TPR regions). Based on this structural similarity, functional studies suggest that, RagB binding of glycans occurs at pockets on the molecular surface that are distinct from those of SusD.


Pssm-ID: 429768  Cd Length: 294  Bit Score: 92.17  E-value: 1.27e-20
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  251 SITEVMIKDGEYSLQKDYMSIWSPSNQRNSEVifpipnfPEGGLGNCFLAHALPADYVSQNGIALTKWGGFLVPWDFYDT 330
Cdd:pfam07980   3 SIFEVQYDSGVTGGGGRSYGVNLGPNGGAGGG-------EGGGWGGLGPTQDLVDLFYMADGSPIFDTDDDSDGTDTIEI 75
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  331 YDPKDKRRNALLATYWN----------GKKMVDRRTEYTGKPGAVPMKYQENP---------------STTGQWDASEYV 385
Cdd:pfam07980  76 DGNRDPRFYATVAFDGCtwnagsnnlvYVAGKYTDGNLGSGDTGAPNSDGNRSntgyllrkfvdedgdSSGGGGSSIDFP 155
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  386 INRYAEVILARAEALNEIyGPTQEAKDLVHEIRERAFDNYKGSKyekeinDITDKDAFRAHLLKERGWEFCWEGMRRPDL 465
Cdd:pfam07980 156 VIRYAEVLLNYAEALNEL-GGPEEAIKYINKIRERAGLPDLTDS------AYGSQEELIDAIRDERRIELAGEGHRFFDL 228
                         250       260       270       280       290       300
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 496136230  466 IRHGELI----------------------SNAIARGKLMAEPKHILYAIPQSVIYENPNLKNNEG 508
Cdd:pfam07980 229 RRWKKALqelnglfgggnayngsnkgldnFILERPDELEDNFKHYLLPIPQSEIDRNPGLTQNPG 293
SusD cd08977
starch binding outer membrane protein SusD; SusD-like proteins from Bacteroidetes, members of ...
37-469 1.73e-18

starch binding outer membrane protein SusD; SusD-like proteins from Bacteroidetes, members of the human distal gut microbiota, are part of the starch utilization system (Sus). Sus is one of the large clusters of glycosyl hydrolases, called polysaccharide utilization loci (PULs), which play an important role in polysaccharide recognition and uptake, and it is needed for growth on amylose, amylopectin, pullulan, and maltooligosaccharides. SusD, together with SusC, a predicted beta-barrel porin, forms the minimum outer-membrane starch-binding complex. The adult human distal gut microbiota is essential for digestion of a large variety of dietary polysaccharides, for which humans lack the necessary glycosyl hydrolases.


Pssm-ID: 185760 [Multi-domain]  Cd Length: 359  Bit Score: 87.09  E-value: 1.73e-18
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  37 TENDVKAAVTGIYHELRGGGWDRYNCAW--GSLLTmqigctDECDCNWVWDKQLDFLWTAETTDLGQF---YTGLVPAVT 111
Cdd:cd08977    1 DPTDAEAALTGLYAGLRSSGNYYGGTLGllGDLRA------DD*VAASNSGDYTEVNTNNNPNDSAFGtssWNGVYTNIN 74
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 112 KATSLLERM-RKISISAPIKRRYMAEVRCLRAMWAYDLYDLYGTVPLITDPDIALDPqkaqsymPERPSIEWYVNFIDTE 190
Cdd:cd08977   75 NANIFLEKIdEASELTEANRNRYKGEAKFIRALAYFYLTRLFGGVPLSTAADQGTET-------PPRDSQEEVYTQILAD 147
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 191 LKEAEENLKPAS----LLAASEYGRMTKGIAQMYMLKLYMHEAGQERHYrndegkammwWNRVDSITEVMIKDGEYSLQK 266
Cdd:cd08977  148 LDEAIALLPEASsaqdFYIYFGDGRAWKKAARALLARVYLYLANYTAAD----------YAEALTAAEKSFKGGVTLLTN 217
                        250       260       270       280       290       300       310       320
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 267 DYmsIWSPSNqrNSEVIFPIPNFPEGGLGNCFLAHALPADyvsqngialtkWGGFLVPWDFYDTYD-PKDKRrnallaty 345
Cdd:cd08977  218 LF--GENAAN--SKEDIFEIYYADSGDNSNPLGSLNNNNG-----------YANFRVSADIIDKLDgYGDPR-------- 274
                        330       340       350       360       370       380       390       400
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 346 wngkkmvdrrteytgkpgavpmkyqenpsttgqWDASEYVINRYAEVILARAEALNEIyGPTQEAKDLVHEIRERAFDNy 425
Cdd:cd08977  275 ---------------------------------LSLAPIPIIRYAEVLLLRAEALARL-GNGADAIEYLNAVRRRSGGN- 319
                        410       420       430       440
                 ....*....|....*....|....*....|....*....|....
gi 496136230 426 kgskYEKEINDITDKDAFRAHLLKERGWEFCWEGMRRPDLIRHG 469
Cdd:cd08977  320 ----AANNTSQASTAEELLEEILDERRLELFGEGHRWYDLRRTG 359
 
Name Accession Description Interval E-value
SusD_RagB pfam07980
SusD family; This domain is found in bacterial cell surface proteins such SusD and SusD-like ...
251-508 1.27e-20

SusD family; This domain is found in bacterial cell surface proteins such SusD and SusD-like proteins as well RagB, outer membrane surface receptor antigen. Bacteroidetes, one of the two dominant bacterial phyla in the human gut, are Gram-negative saccharolytic microorganizms that utilize a diverse array of glycans. Hence, they express starch-utilization system (Sus) for glycan uptake. SusD has 551 amino acids, and is almost entirely alpha-helical, with 22 alpha-helices, eight of which form 4 tetra-trico peptide repeats (TPRs: helix-turn-helix motifs involved in protein-protein interactions). The four TPRs pack together to create a right-handed super-helix. This is predicted to mediate the formation of SusD and SusC porin complex at the cell surface. The interaction between SusC and TPR1/TPR2 region of SusD is predicted to be of functional importance since it allows SusD to be in position for oligosaccharide capture from other Sus lipoproteins and delivery of these glycans to the SusC porin. The non-TPR containing portion of SusD is where starch binding occurs. The binding site is a shallow surface cavity located on top of TPR1. SusD homologs such as SusD-like proteins have a critical role in carbohydrate acquisition. Both SusD and its homologs, contain 15-20 residues at the N-terminus that might be a flexible linker region, anchoring the protein to the membrane and the glycan-binding domain. Other homologs to SusD have been examined in Porphyromonas gingivalis such as RagB, an immunodominant outer-membrane surface receptor antigen. Structural characterization of RagB shows substantial similarity with Bacteroides thetaiotaomicron SusD (i.e alpha-helices and TPR regions). Based on this structural similarity, functional studies suggest that, RagB binding of glycans occurs at pockets on the molecular surface that are distinct from those of SusD.


Pssm-ID: 429768  Cd Length: 294  Bit Score: 92.17  E-value: 1.27e-20
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  251 SITEVMIKDGEYSLQKDYMSIWSPSNQRNSEVifpipnfPEGGLGNCFLAHALPADYVSQNGIALTKWGGFLVPWDFYDT 330
Cdd:pfam07980   3 SIFEVQYDSGVTGGGGRSYGVNLGPNGGAGGG-------EGGGWGGLGPTQDLVDLFYMADGSPIFDTDDDSDGTDTIEI 75
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  331 YDPKDKRRNALLATYWN----------GKKMVDRRTEYTGKPGAVPMKYQENP---------------STTGQWDASEYV 385
Cdd:pfam07980  76 DGNRDPRFYATVAFDGCtwnagsnnlvYVAGKYTDGNLGSGDTGAPNSDGNRSntgyllrkfvdedgdSSGGGGSSIDFP 155
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  386 INRYAEVILARAEALNEIyGPTQEAKDLVHEIRERAFDNYKGSKyekeinDITDKDAFRAHLLKERGWEFCWEGMRRPDL 465
Cdd:pfam07980 156 VIRYAEVLLNYAEALNEL-GGPEEAIKYINKIRERAGLPDLTDS------AYGSQEELIDAIRDERRIELAGEGHRFFDL 228
                         250       260       270       280       290       300
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 496136230  466 IRHGELI----------------------SNAIARGKLMAEPKHILYAIPQSVIYENPNLKNNEG 508
Cdd:pfam07980 229 RRWKKALqelnglfgggnayngsnkgldnFILERPDELEDNFKHYLLPIPQSEIDRNPGLTQNPG 293
SusD cd08977
starch binding outer membrane protein SusD; SusD-like proteins from Bacteroidetes, members of ...
37-469 1.73e-18

starch binding outer membrane protein SusD; SusD-like proteins from Bacteroidetes, members of the human distal gut microbiota, are part of the starch utilization system (Sus). Sus is one of the large clusters of glycosyl hydrolases, called polysaccharide utilization loci (PULs), which play an important role in polysaccharide recognition and uptake, and it is needed for growth on amylose, amylopectin, pullulan, and maltooligosaccharides. SusD, together with SusC, a predicted beta-barrel porin, forms the minimum outer-membrane starch-binding complex. The adult human distal gut microbiota is essential for digestion of a large variety of dietary polysaccharides, for which humans lack the necessary glycosyl hydrolases.


Pssm-ID: 185760 [Multi-domain]  Cd Length: 359  Bit Score: 87.09  E-value: 1.73e-18
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230  37 TENDVKAAVTGIYHELRGGGWDRYNCAW--GSLLTmqigctDECDCNWVWDKQLDFLWTAETTDLGQF---YTGLVPAVT 111
Cdd:cd08977    1 DPTDAEAALTGLYAGLRSSGNYYGGTLGllGDLRA------DD*VAASNSGDYTEVNTNNNPNDSAFGtssWNGVYTNIN 74
                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 112 KATSLLERM-RKISISAPIKRRYMAEVRCLRAMWAYDLYDLYGTVPLITDPDIALDPqkaqsymPERPSIEWYVNFIDTE 190
Cdd:cd08977   75 NANIFLEKIdEASELTEANRNRYKGEAKFIRALAYFYLTRLFGGVPLSTAADQGTET-------PPRDSQEEVYTQILAD 147
                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 191 LKEAEENLKPAS----LLAASEYGRMTKGIAQMYMLKLYMHEAGQERHYrndegkammwWNRVDSITEVMIKDGEYSLQK 266
Cdd:cd08977  148 LDEAIALLPEASsaqdFYIYFGDGRAWKKAARALLARVYLYLANYTAAD----------YAEALTAAEKSFKGGVTLLTN 217
                        250       260       270       280       290       300       310       320
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 267 DYmsIWSPSNqrNSEVIFPIPNFPEGGLGNCFLAHALPADyvsqngialtkWGGFLVPWDFYDTYD-PKDKRrnallaty 345
Cdd:cd08977  218 LF--GENAAN--SKEDIFEIYYADSGDNSNPLGSLNNNNG-----------YANFRVSADIIDKLDgYGDPR-------- 274
                        330       340       350       360       370       380       390       400
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 496136230 346 wngkkmvdrrteytgkpgavpmkyqenpsttgqWDASEYVINRYAEVILARAEALNEIyGPTQEAKDLVHEIRERAFDNy 425
Cdd:cd08977  275 ---------------------------------LSLAPIPIIRYAEVLLLRAEALARL-GNGADAIEYLNAVRRRSGGN- 319
                        410       420       430       440
                 ....*....|....*....|....*....|....*....|....
gi 496136230 426 kgskYEKEINDITDKDAFRAHLLKERGWEFCWEGMRRPDLIRHG 469
Cdd:cd08977  320 ----AANNTSQASTAEELLEEILDERRLELFGEGHRWYDLRRTG 359
 
Blast search parameters
Data Source: Precalculated data, version = cdd.v.3.21
Preset Options:Database: CDSEARCH/cdd   Low complexity filter: no  Composition Based Adjustment: yes   E-value threshold: 0.01

References:

  • Wang J et al. (2023), "The conserved domain database in 2023", Nucleic Acids Res.51(D)384-8.
  • Lu S et al. (2020), "The conserved domain database in 2020", Nucleic Acids Res.48(D)265-8.
  • Marchler-Bauer A et al. (2017), "CDD/SPARCLE: functional classification of proteins via subfamily domain architectures.", Nucleic Acids Res.45(D)200-3.
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