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(-) Description

Title :  TOXOPLASMA GONDII HYPOXANTHINE-GUANINE PHOSPHORIBOSYLTRANSFERASE GMP COMPLEX
 
Authors :  A. Heroux, E. L. White, L. J. Ross, D. W. Borhani
Date :  09 Jul 99  (Deposition) - 17 Oct 99  (Release) - 24 Feb 09  (Revision)
Method :  X-RAY DIFFRACTION
Resolution :  1.65
Chains :  Asym./Biol. Unit :  A,B,C,D
Keywords :  Transferase, Glycosyltransferase, Purine Salvage (Keyword Search: [Gene Ontology, PubMed, Web (Google)] )
 
Reference :  A. Heroux, E. L. White, L. J. Ross, D. W. Borhani
Crystal Structures Of The Toxoplasma Gondii Hypoxanthine-Guanine Phosphoribosyltransferase Gmp And -Imp Complexes: Comparison Of Purine Binding Interactions With The Xmp Complex
Biochemistry V. 38 14485 1999
PubMed-ID: 10545170  |  Reference-DOI: 10.1021/BI990507Q
(for further references see the PDB file header)

(-) Compounds

Molecule 1 - HYPOXANTHINE-GUANINE PHOSPHORIBOSYLTRANSFERASE
    Chains: A, B, C, D
    EC Number: 2.4.2.8
    Engineered: YES
    Expression System: ESCHERICHIA COLI
    Expression System Plasmid: PETC1
    Expression System Strain: BL21(DE3)
    Expression System Taxid: 469008
    Expression System Vector: PET15B
    Organism Scientific: TOXOPLASMA GONDII
    Organism Taxid: 383379
    Strain: RH
    Synonym: HGPRTASE

 Structural Features

(-) Chains, Units

  1234
Asymmetric/Biological Unit : ABCD

Summary Information (see also Sequences/Alignments below)

(-) Ligands, Modified Residues, Ions  (1, 4)

Asymmetric/Biological Unit (1, 4)
No.NameCountTypeFull Name
15GP4Ligand/IonGUANOSINE-5'-MONOPHOSPHATE

(-) Sites  (4, 4)

Asymmetric Unit (4, 4)
No.NameEvidenceResiduesDescription
1AC1SOFTWAREGLU A:146 , ILE A:148 , ASP A:150 , THR A:151 , GLY A:152 , THR A:154 , LYS A:178 , TRP A:199 , ILE A:200 , TYR A:205 , ASP A:206 , HOH A:2179 , HOH A:2180 , HOH A:2181 , HOH A:2182 , GLY B:125BINDING SITE FOR RESIDUE 5GP A 300
2AC2SOFTWAREGLY A:125 , LYS B:79 , GLU B:146 , ILE B:148 , ASP B:150 , THR B:151 , GLY B:152 , THR B:154 , LYS B:178 , TRP B:199 , ILE B:200 , ASP B:206 , HOH B:2112 , HOH B:2139 , HOH B:2157 , HOH B:2158 , HOH B:2159BINDING SITE FOR RESIDUE 5GP B 300
3AC3SOFTWAREGLU C:146 , ASP C:147 , ASP C:150 , THR C:151 , GLY C:152 , THR C:154 , LYS C:178 , VAL C:198 , TRP C:199 , ILE C:200 , TYR C:205 , ASP C:206 , HOH C:2146 , HOH C:2147 , HOH C:2148 , HOH C:2149 , HOH C:2150 , HOH C:2151 , HOH C:2152BINDING SITE FOR RESIDUE 5GP C 300
4AC4SOFTWARELYS D:79 , GLU D:146 , ASP D:147 , ASP D:150 , THR D:151 , GLY D:152 , PHE D:153 , THR D:154 , LYS D:178 , TRP D:199 , ILE D:200 , ASP D:206 , HOH D:2088 , HOH D:2145 , HOH D:2146 , HOH D:2147 , HOH D:2148 , HOH D:2149 , HOH D:2150BINDING SITE FOR RESIDUE 5GP D 300

(-) SS Bonds  (0, 0)

(no "SS Bond" information available for 1QK3)

(-) Cis Peptide Bonds  (0, 0)

(no "Cis Peptide Bond" information available for 1QK3)

 Sequence-Structure Mapping

(-) SAPs(SNPs)/Variants  (0, 0)

(no "SAP(SNP)/Variant" information available for 1QK3)

(-) PROSITE Motifs  (1, 4)

Asymmetric/Biological Unit (1, 4)
 PROSITEUniProtKBPDB
No.IDACDescriptionIDLocationCountLocation
1PUR_PYR_PR_TRANSFERPS00103 Purine/pyrimidine phosphoribosyl transferases signature.HGXR_TOXGO142-154
 
 
 		  4A:142-154
B:142-154
C:142-154
D:142-154

(-) Exons   (0, 0)

(no "Exon" information available for 1QK3)

(-) Sequences/Alignments

Asymmetric/Biological Unit
   Reformat: Number of residues per line =  ('0' or empty: single-line sequence representation)
  Number of residues per labelling interval =   
  UniProt sequence: complete  aligned part    
   Show mapping: SCOP domains CATH domains Pfam domains Secondary structure (by author)
SAPs(SNPs) PROSITE motifs Exons
(details for a mapped element are shown in a popup box when the mouse pointer rests over it) 
Chain A from PDB  Type:PROTEIN  Length:228
 aligned with HGXR_TOXGO | Q26997 from UniProtKB/Swiss-Prot  Length:230

    Alignment length:228
                                    10        20        30        40        50        60        70        80        90       100       110       120       130       140       150       160       170       180       190       200       210       220        
           HGXR_TOXGO     1 MASKPIEDYGKGKGRIEPMYIPDNTFYNADDFLVPPHCKPYIDKILLPGGLVKDRVEKLAYDIHRTYFGEELHIICILKGSRGFFNLLIDYLATIQKYSGRESSVPPFFEHYVRLKSYQNDNSTGQLTVLSDDLSIFRDKHVLIVEDIVDTGFTLTEFGERLKAVGPKSMRIATLVEKRTDRSNSLKGDFVGFSIEDVWIVGCCYDFNEMFRDFDHVAVLSDAARKKF 228
               SCOP domains d1qk3a_ A: Hypoxanthine-guanine-xanthine PRTase                                                                                                                                                                                      SCOP domains
               CATH domains 1qk3A00 A:1-228  [code=3.40.50.2020, no name defined]                                                                                                                                                                                CATH domains
               Pfam domains ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ Pfam domains
         Sec.struct. author ....hhhhh....................hhh..hhhhhhhh.....hhhhhhhhhhhhhhhhhhhhh...eeeeee.....hhhhhhhhhhhhhhhh..........eeeee....................hhhhh..eeeeee.....hhhhhhhhhhhhh....eeeeee.eeee.............eeee........................hhhhhhhh Sec.struct. author
                 SAPs(SNPs) ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ SAPs(SNPs)
                    PROSITE ---------------------------------------------------------------------------------------------------------------------------------------------PUR_PYR_PR_TR-------------------------------------------------------------------------- PROSITE
                 Transcript ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ Transcript
                 1qk3 A   1 MASKPIEDYGKGKGRIEPMYIPDNTFYNADDFLVPPHCKPYIDKILLPGGLVKDRVEKLAYDIHRTYFGEELHIICILKGSRGFFNLLIDYLATIQKYSGRESSVPPFFEHYVRLKSYQNDNSTGQLTVLSDDLSIFRDKHVLIVEDIVDTGFTLTEFGERLKAVGPKSMRIATLVEKRTDRSNSLKGDFVGFSIEDVWIVGCCYDFNEMFRDFDHVAVLSDAARKKF 228
                                    10        20        30        40        50        60        70        80        90       100       110       120       130       140       150       160       170       180       190       200       210       220        


Chain B from PDB  Type:PROTEIN  Length:231
 aligned with HGXR_TOXGO | Q26997 from UniProtKB/Swiss-Prot  Length:230

    Alignment length:231
                               1                                                                                                                                                                                                                                   
                               |     7        17        27        37        47        57        67        77        87        97       107       117       127       137       147       157       167       177       187       197       207       217       227 
           HGXR_TOXGO     - ---MASKPIEDYGKGKGRIEPMYIPDNTFYNADDFLVPPHCKPYIDKILLPGGLVKDRVEKLAYDIHRTYFGEELHIICILKGSRGFFNLLIDYLATIQKYSGRESSVPPFFEHYVRLKSYQNDNSTGQLTVLSDDLSIFRDKHVLIVEDIVDTGFTLTEFGERLKAVGPKSMRIATLVEKRTDRSNSLKGDFVGFSIEDVWIVGCCYDFNEMFRDFDHVAVLSDAARKKF 228
               SCOP domains d1qk3b_ B: Hypoxanthine-guanine-xanthine PRTase                                                                                                                                                                                         SCOP domains
               CATH domains 1qk3B00 B:0A-228  [code=3.40.50.2020, no name defined]                                                                                                                                                                                  CATH domains
               Pfam domains --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Pfam domains
         Sec.struct. author .......hhhhh....................hhh..hhhhhhhh.....hhhhhhhhhhhhhhhhhhhh....eeeeee.....hhhhhhhhhhhhhhhhhhhhh.....eeeee....................hhhhh..eeeeee.....hhhhhhhhhhhhh....eeeeee.eee..............eee.........................hhhhhhh. Sec.struct. author
                 SAPs(SNPs) --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- SAPs(SNPs)
                    PROSITE ------------------------------------------------------------------------------------------------------------------------------------------------PUR_PYR_PR_TR-------------------------------------------------------------------------- PROSITE
                 Transcript --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Transcript
                 1qk3 B  0A GSHMASKPIEDYGKGKGRIEPMYIPDNTFYNADDFLVPPHCKPYIDKILLPGGLVKDRVEKLAYDIHRTYFGEELHIICILKGSRGFFNLLIDYLATIQKYSGRESSVPPFFEHYVRLKSYQNDNSTGQLTVLSDDLSIFRDKHVLIVEDIVDTGFTLTEFGERLKAVGPKSMRIATLVEKRTDRSNSLKGDFVGFSIEDVWIVGCCYDFNEMFRDFDHVAVLSDAARKKF 228
                            |||      7        17        27        37        47        57        67        77        87        97       107       117       127       137       147       157       167       177       187       197       207       217       227 
                           0A||                                                                                                                                                                                                                                    
                            0B|                                                                                                                                                                                                                                    
                             0C                                                                                                                                                                                                                                    


Chain C from PDB  Type:PROTEIN  Length:213
 aligned with HGXR_TOXGO | Q26997 from UniProtKB/Swiss-Prot  Length:230

    Alignment length:232
                               1                                                                                                                                                                                                                                    
                               |     7        17        27        37        47        57        67        77        87        97       107       117       127       137       147       157       167       177       187       197       207       217       227  
           HGXR_TOXGO     - ---MASKPIEDYGKGKGRIEPMYIPDNTFYNADDFLVPPHCKPYIDKILLPGGLVKDRVEKLAYDIHRTYFGEELHIICILKGSRGFFNLLIDYLATIQKYSGRESSVPPFFEHYVRLKSYQNDNSTGQLTVLSDDLSIFRDKHVLIVEDIVDTGFTLTEFGERLKAVGPKSMRIATLVEKRTDRSNSLKGDFVGFSIEDVWIVGCCYDFNEMFRDFDHVAVLSDAARKKFE 229
               SCOP domains d1qk3c_ C: Hypoxanthine-guanine-xanthine PRTase                                                                                                                                                                                          SCOP domains
               CATH domains 1qk3C00 C:0A-229  [code=3.40.50.2020, no name defined]                                                                                                                                                                                   CATH domains
               Pfam domains ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Pfam domains
         Sec.struct. author .......hhhhh..................hhhhh..hhhhhhhh.....hhhhhhhhhhhhhhhhhhhh....eeeeee....hhhhhhhhhhhhhhhhhh.........eeeee..-----------------hhhhhh..eeeeee.....hhhhhhhhhhhhh....eeeeee.eeee...--........eeee........................hhhhhhh.. Sec.struct. author
                 SAPs(SNPs) ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- SAPs(SNPs)
                    PROSITE ------------------------------------------------------------------------------------------------------------------------------------------------PUR_PYR_PR_TR--------------------------------------------------------------------------- PROSITE
                 Transcript ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Transcript
                 1qk3 C  0A GSHMASKPIEDYGKGKGRIEPMYIPDNTFYNADDFLVPPHCKPYIDKILLPGGLVKDRVEKLAYDIHRTYFGEELHIICILKGSRGFFNLLIDYLATIQKYSGRESSVPPFFEHYVRL-----------------DLSIFRDKHVLIVEDIVDTGFTLTEFGERLKAVGPKSMRIATLVEKRTDR--SLKGDFVGFSIEDVWIVGCCYDFNEMFRDFDHVAVLSDAARKKFE 229
                            |||      7        17        27        37        47        57        67        77        87        97       107       | -         -     | 137       147       157       167       177    |  187       197       207       217       227  
                           0A||                                                                                                                115               133                                              182  |                                            
                            0B|                                                                                                                                                                                      185                                            
                             0C                                                                                                                                                                                                                                     


Chain D from PDB  Type:PROTEIN  Length:227
 aligned with HGXR_TOXGO | Q26997 from UniProtKB/Swiss-Prot  Length:230

    Alignment length:229
                                    10        20        30        40        50        60        70        80        90       100       110       120       130       140       150       160       170       180       190       200       210       220         
           HGXR_TOXGO     1 MASKPIEDYGKGKGRIEPMYIPDNTFYNADDFLVPPHCKPYIDKILLPGGLVKDRVEKLAYDIHRTYFGEELHIICILKGSRGFFNLLIDYLATIQKYSGRESSVPPFFEHYVRLKSYQNDNSTGQLTVLSDDLSIFRDKHVLIVEDIVDTGFTLTEFGERLKAVGPKSMRIATLVEKRTDRSNSLKGDFVGFSIEDVWIVGCCYDFNEMFRDFDHVAVLSDAARKKFE 229
               SCOP domains d1qk3d_ D: Hypoxanthine-guanine-xanthine PRTase                                                                                                                                                                                       SCOP domains
               CATH domains 1qk3D00 D:1-229  [code=3.40.50.2020, no name defined]                                                                                                                                                                                 CATH domains
               Pfam domains ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Pfam domains
         Sec.struct. author ....hhhhh....................hhh..hhhhhhhh.....hhhhhhhhhhhhhhhhhhhh....eeeeee....hhhhhhhhhhhhhhhhhh.........eeeee.eeeee.......eeeee..hhhhh..eeeeee.....hhhhhhhhhhhhh....eeeeee.eee....--........eee.........................hhhhhhhhh Sec.struct. author
                 SAPs(SNPs) ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- SAPs(SNPs)
                    PROSITE ---------------------------------------------------------------------------------------------------------------------------------------------PUR_PYR_PR_TR--------------------------------------------------------------------------- PROSITE
                 Transcript ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Transcript
                 1qk3 D   1 MASKPIEDYGKGKGRIEPMYIPDNTFYNADDFLVPPHCKPYIDKILLPGGLVKDRVEKLAYDIHRTYFGEELHIICILKGSRGFFNLLIDYLATIQKYSGRESSVPPFFEHYVRLKSYQNDNSTGQLTVLSDDLSIFRDKHVLIVEDIVDTGFTLTEFGERLKAVGPKSMRIATLVEKRTDR--SLKGDFVGFSIEDVWIVGCCYDFNEMFRDFDHVAVLSDAARKKFE 229
                                    10        20        30        40        50        60        70        80        90       100       110       120       130       140       150       160       170       180 |  |  190       200       210       220         
                                                                                                                                                                                                               182  |                                            
                                                                                                                                                                                                                  185
   Legend:   → Mismatch (orange background)
  - → Gap (green background, '-', border residues have a numbering label)
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  x → Chemical Group (purple background, 'x', labelled with number + name, e.g. ACE or NH2)
  extra numbering lines below/above indicate numbering irregularities and modified residue names etc., number ends below/above '|'

 Classification and Annotation

(-) SCOP Domains  (1, 4)

Asymmetric/Biological Unit
(-)
Class: Alpha and beta proteins (a/b) (23833)

(-) CATH Domains  (1, 4)

Asymmetric/Biological Unit
(-)
Class: Alpha Beta (26913)

(-) Pfam Domains  (0, 0)

(no "Pfam Domain" information available for 1QK3)

(-) Gene Ontology  (13, 13)

Asymmetric/Biological Unit(hide GO term definitions)
Chain A,B,C,D   (HGXR_TOXGO | Q26997)
molecular function
    GO:0052657    guanine phosphoribosyltransferase activity    Catalysis of the reaction: GMP + diphosphate = guanine + 5-phospho-alpha-D-ribose 1-diphosphate.
    GO:0004422    hypoxanthine phosphoribosyltransferase activity    Catalysis of the reaction: IMP + diphosphate = hypoxanthine + 5-phospho-alpha-D-ribose 1-diphosphate.
    GO:0046872    metal ion binding    Interacting selectively and non-covalently with any metal ion.
    GO:0000166    nucleotide binding    Interacting selectively and non-covalently with a nucleotide, any compound consisting of a nucleoside that is esterified with (ortho)phosphate or an oligophosphate at any hydroxyl group on the ribose or deoxyribose.
    GO:0016740    transferase activity    Catalysis of the transfer of a group, e.g. a methyl group, glycosyl group, acyl group, phosphorus-containing, or other groups, from one compound (generally regarded as the donor) to another compound (generally regarded as the acceptor). Transferase is the systematic name for any enzyme of EC class 2.
    GO:0016757    transferase activity, transferring glycosyl groups    Catalysis of the transfer of a glycosyl group from one compound (donor) to another (acceptor).
    GO:0000310    xanthine phosphoribosyltransferase activity    Catalysis of the reaction: 5-phospho-alpha-D-ribose 1-diphosphate + xanthine = (9-D-ribosylxanthine)-5'-phosphate + diphosphate.
biological process
    GO:0032263    GMP salvage    Any process which produces guanosine monophosphate from derivatives of it, without de novo synthesis.
    GO:0032264    IMP salvage    Any process which produces inosine monophosphate from derivatives of it, without de novo synthesis.
    GO:0032265    XMP salvage    Any process which produces xanthosine monophosphate from derivatives of it, without de novo synthesis.
    GO:0009116    nucleoside metabolic process    The chemical reactions and pathways involving a nucleoside, a nucleobase linked to either beta-D-ribofuranose (a ribonucleoside) or 2-deoxy-beta-D-ribofuranose, (a deoxyribonucleoside), e.g. adenosine, guanosine, inosine, cytidine, uridine and deoxyadenosine, deoxyguanosine, deoxycytidine and thymidine (= deoxythymidine).
    GO:0006166    purine ribonucleoside salvage    Any process which produces a purine nucleoside from derivatives of it, without de novo synthesis.
cellular component
    GO:0005737    cytoplasm    All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.

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  1qk3
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  HGXR_TOXGO | Q26997
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 Related Entries

(-) Entries Sharing at Least One Protein Chain (UniProt ID)

UniProtKB/Swiss-Prot
        HGXR_TOXGO | Q26997: 1dbr 1fsg 1qk4 1qk5

(-) Related Entries Specified in the PDB File

1dbr HYPOXANTHINE GUANINE XANTHINE
1hmp HYPOXANTHINE GUANINE PHOSPHORIBOSYLTRANSFERASE
1qk3 HYPOXANTHINE GUANINE PHOSPHORIBOSYLTRANSFERASE
1qk5 HYPOXANTHINE GUANINE PHOSPHORIBOSYLTRANSFERASE