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(-) Description

Title :  ANALYSIS OF AN INVARIANT ASPARTIC ACID IN HPRTS-GLUTAMINE MUTANT
 
Authors :  B. Canyuk, P. J. Focia, A. E. Eakin
Date :  29 Jan 01  (Deposition) - 29 May 02  (Release) - 24 Feb 09  (Revision)
Method :  X-RAY DIFFRACTION
Resolution :  2.06
Chains :  Asym./Biol. Unit :  A,B
Keywords :  Phosphoribosyltransferase, Nucleotide Metabolism, Purine Salvage, Ternary Complex, Catalytic Base (Keyword Search: [Gene Ontology, PubMed, Web (Google)] )
 
Reference :  B. Canyuk, P. J. Focia, A. E. Eakin
The Role For An Invariant Aspartic Acid In Hypoxanthine Phosphoribosyltransferases Is Examined Using Saturation Mutagenesis, Functional Analysis, And X-Ray Crystallography.
Biochemistry V. 40 2754 2001
PubMed-ID: 11258886  |  Reference-DOI: 10.1021/BI001195Q
(for further references see the PDB file header)

(-) Compounds

Molecule 1 - HYPOXANTHINE-GUANINE PHOSPHORIBOSYLTRANSFERASE
    Chains: A, B
    EC Number: 2.4.2.8
    Engineered: YES
    Expression System: ESCHERICHIA COLI
    Expression System Taxid: 562
    Mutation: YES
    Organism Scientific: TRYPANOSOMA CRUZI
    Organism Taxid: 5693

 Structural Features

(-) Chains, Units

  12
Asymmetric/Biological Unit : AB

Summary Information (see also Sequences/Alignments below)

(-) Ligands, Modified Residues, Ions  (3, 8)

Asymmetric/Biological Unit (3, 8)
No.NameCountTypeFull Name
17HP2Ligand/Ion7-HYDROXY-PYRAZOLO[4,3-D]PYRIMIDINE
2MG4Ligand/IonMAGNESIUM ION
3PRP2Ligand/IonALPHA-PHOSPHORIBOSYLPYROPHOSPHORIC ACID

(-) Sites  (8, 8)

Asymmetric Unit (8, 8)
No.NameEvidenceResiduesDescription
1AC1SOFTWAREGLU A:111 , ASP A:112 , PRP A:801 , HOH A:1301 , HOH A:1302BINDING SITE FOR RESIDUE MG A 900
2AC2SOFTWAREASP A:171 , PRP A:801 , HOH A:1303 , HOH A:1304 , HOH A:1305BINDING SITE FOR RESIDUE MG A 902
3AC3SOFTWAREASP B:171 , PRP B:811 , HOH B:1306 , HOH B:1307 , HOH B:1308BINDING SITE FOR RESIDUE MG B 912
4AC4SOFTWAREPRP B:811 , HOH B:1309 , HOH B:1310BINDING SITE FOR RESIDUE MG B 910
5AC5SOFTWAREGLN A:115 , LYS A:143 , ALA A:163 , PHE A:164 , VAL A:165 , ASP A:171 , PRP A:801BINDING SITE FOR RESIDUE 7HP A 800
6AC6SOFTWARETYR B:82 , GLN B:115 , LYS B:143 , ALA B:163 , PHE B:164 , VAL B:165 , LEU B:170 , ASP B:171 , PRP B:811 , HOH B:1308BINDING SITE FOR RESIDUE 7HP B 810
7AC7SOFTWARELYS A:52 , GLY A:53 , GLU A:111 , ASP A:112 , ILE A:113 , VAL A:114 , GLN A:115 , THR A:116 , ALA A:117 , ASP A:171 , ARG A:177 , 7HP A:800 , MG A:900 , MG A:902 , HOH A:1068 , HOH A:1069 , HOH A:1073 , HOH A:1074 , HOH A:1277 , HOH A:1278 , HOH A:1302 , HOH A:1303 , HOH A:1305BINDING SITE FOR RESIDUE PRP A 801
8AC8SOFTWARELYS B:52 , GLY B:53 , SER B:81 , TYR B:82 , GLU B:111 , ASP B:112 , ILE B:113 , GLN B:115 , THR B:116 , ALA B:117 , THR B:119 , ASP B:171 , ARG B:177 , 7HP B:810 , MG B:910 , MG B:912 , HOH B:1025 , HOH B:1026 , HOH B:1027 , HOH B:1028 , HOH B:1029 , HOH B:1031 , HOH B:1306 , HOH B:1308 , HOH B:1310BINDING SITE FOR RESIDUE PRP B 811

(-) SS Bonds  (0, 0)

(no "SS Bond" information available for 1I0I)

(-) Cis Peptide Bonds  (2, 2)

Asymmetric/Biological Unit
No.Residues
1Leu A:51 -Lys A:52
2Leu B:51 -Lys B:52

 Sequence-Structure Mapping

(-) SAPs(SNPs)/Variants  (0, 0)

(no "SAP(SNP)/Variant" information available for 1I0I)

(-) PROSITE Motifs  (0, 0)

(no "PROSITE Motif" information available for 1I0I)

(-) Exons   (0, 0)

(no "Exon" information available for 1I0I)

(-) 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:187
 aligned with Q27796_TRYCR | Q27796 from UniProtKB/TrEMBL  Length:221

    Alignment length:187
                                    14        24        34        44        54        64        74        84        94       104       114       124       134       144       154       164       174       184       
         Q27796_TRYCR     5 YEFAEKILFTEEEIRTRIMEVAKRIADDYKGKGLRPYVNPLVLISVLKGSFMFTADLCRALSDFNVPVRMEFICVSSYGEGVTSSGQVRMLLDTRHSIEGHHVLIVEDIVDTALTLNYLYHMYFTRRPASLKTVVLLDKREGRRVPFSADYVVANIPNAFVIGYGLDYDDTYRELRDIVVLRPEVYA 191
               SCOP domains d1i0ia_ A: Hypoxanthine PRTase                                                                                                                                                              SCOP domains
               CATH domains 1i0iA00 A:5-191  [code=3.40.50.2020, no name defined]                                                                                                                                       CATH domains
               Pfam domains ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Pfam domains
         Sec.struct. author ...eeeeeehhhhhhhhhhhhhhhhhhhhh..........eeeeee...hhhhhhhhhhhhhhh...eeeeeeeee............eeee.........eeeeeeeee..hhhhhhhhhhhhh....eeeeeeeee.hhhh.......eeeee.....ee...............eeee...... Sec.struct. author
                 SAPs(SNPs) ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- SAPs(SNPs)
                    PROSITE ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- PROSITE
                 Transcript ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Transcript
                 1i0i A   5 YEFAEKILFTEEEIRTRIKEVAKRIADDYKGKGLRPYVNPLVLISVLKGSFMFTADLCRALCDFNVPVRMEFICVSSYGEGLTSSGQVRMLLDTRHSIEGHHVLIVEDIVQTALTLNYLYHMYFTRRPASLKTVVLLDKREGRRVPFSADYVVANIPNAFVIGYGLDYDDTYRELRDIVVLRPEVYA 191
                                    14        24        34        44        54        64        74        84        94       104       114       124       134       144       154       164       174       184       


Chain A from PDB  Type:PROTEIN  Length:187
 aligned with Q4DRC4_TRYCC | Q4DRC4 from UniProtKB/TrEMBL  Length:241

    Alignment length:187
                                    34        44        54        64        74        84        94       104       114       124       134       144       154       164       174       184       194       204       
         Q4DRC4_TRYCC    25 YEFAEKILFTEEEIRTRIKEVAKRIADDYKGKGLRPYVNPLVLISVLKGSFMFTADLCRALCDFNVPVRMEFICVSSYGEGLTSSGQVRMLLDTRHSIEGHHVLIVEDIVDTALTLNYLYHMYFTRRPASLKTVVLLDKREGRRVPFSADYVVANIPNAFVIGYGLDYDDTYRELRDIVVLRPEVYA 211
               SCOP domains d1i0ia_ A: Hypoxanthine PRTase                                                                                                                                                              SCOP domains
               CATH domains 1i0iA00 A:5-191  [code=3.40.50.2020, no name defined]                                                                                                                                       CATH domains
               Pfam domains ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Pfam domains
         Sec.struct. author ...eeeeeehhhhhhhhhhhhhhhhhhhhh..........eeeeee...hhhhhhhhhhhhhhh...eeeeeeeee............eeee.........eeeeeeeee..hhhhhhhhhhhhh....eeeeeeeee.hhhh.......eeeee.....ee...............eeee...... Sec.struct. author
                 SAPs(SNPs) ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- SAPs(SNPs)
                    PROSITE ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- PROSITE
                 Transcript ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Transcript
                 1i0i A   5 YEFAEKILFTEEEIRTRIKEVAKRIADDYKGKGLRPYVNPLVLISVLKGSFMFTADLCRALCDFNVPVRMEFICVSSYGEGLTSSGQVRMLLDTRHSIEGHHVLIVEDIVQTALTLNYLYHMYFTRRPASLKTVVLLDKREGRRVPFSADYVVANIPNAFVIGYGLDYDDTYRELRDIVVLRPEVYA 191
                                    14        24        34        44        54        64        74        84        94       104       114       124       134       144       154       164       174       184       


Chain B from PDB  Type:PROTEIN  Length:194
 aligned with Q27796_TRYCR | Q27796 from UniProtKB/TrEMBL  Length:221

    Alignment length:201
                                    14        24        34        44        54        64        74        84        94       104       114       124       134       144       154       164       174       184       194       204 
         Q27796_TRYCR     5 YEFAEKILFTEEEIRTRIMEVAKRIADDYKGKGLRPYVNPLVLISVLKGSFMFTADLCRALSDFNVPVRMEFICVSSYGEGVTSSGQVRMLLDTRHSIEGHHVLIVEDIVDTALTLNYLYHMYFTRRPASLKTVVLLDKREGRRVPFSADYVVANIPNAFVIGYGLDYDDTYRELRDIVVLRPEVYAEREAARQKKQRAIG 205
               SCOP domains d1i0ib_ B: Hypoxanthine PRTase                                                                                                                                                                            SCOP domains
               CATH domains 1i0iB00 B:5-198  [code=3.40.50.2020, no name defined]                                                                                                                                                     CATH domains
               Pfam domains --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Pfam domains
         Sec.struct. author ...eeeeeehhhhhhhhhhhhhhhhhhhhhhhh.......eeeeeee..hhhhhhhhhhhhhhh...eeeeeeeee............eeee.........eeeeeeeee..hhhhhhhhhhhhh....eeeeeeeee.hhhh.......eeeee.....ee...............eeeehhhhhhhhhhhh-------h Sec.struct. author
                 SAPs(SNPs) --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- SAPs(SNPs)
                    PROSITE --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- PROSITE
                 Transcript --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Transcript
                 1i0i B   5 YEFAEKILFTEEEIRTRIKEVAKRIADDYKGKGLRPYVNPLVLISVLKGSFMFTADLCRALCDFNVPVRMEFICVSSYGEGLTSSGQVRMLLDTRHSIEGHHVLIVEDIVQTALTLNYLYHMYFTRRPASLKTVVLLDKREGRRVPFSADYVVANIPNAFVIGYGLDYDDTYRELRDIVVLRPEVYAEREAAR-------G 198
                                    14        24        34        44        54        64        74        84        94       104       114       124       134       144       154       164       174       184       194  |      -|
                                                                                                                                                                                                                          197     198


Chain B from PDB  Type:PROTEIN  Length:194
 aligned with Q4DRC4_TRYCC | Q4DRC4 from UniProtKB/TrEMBL  Length:241

    Alignment length:201
                                    34        44        54        64        74        84        94       104       114       124       134       144       154       164       174       184       194       204       214       224 
         Q4DRC4_TRYCC    25 YEFAEKILFTEEEIRTRIKEVAKRIADDYKGKGLRPYVNPLVLISVLKGSFMFTADLCRALCDFNVPVRMEFICVSSYGEGLTSSGQVRMLLDTRHSIEGHHVLIVEDIVDTALTLNYLYHMYFTRRPASLKTVVLLDKREGRRVPFSADYVVANIPNAFVIGYGLDYDDTYRELRDIVVLRPEVYAEREAARQKKQRAIG 225
               SCOP domains d1i0ib_ B: Hypoxanthine PRTase                                                                                                                                                                            SCOP domains
               CATH domains 1i0iB00 B:5-198  [code=3.40.50.2020, no name defined]                                                                                                                                                     CATH domains
               Pfam domains --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Pfam domains
         Sec.struct. author ...eeeeeehhhhhhhhhhhhhhhhhhhhhhhh.......eeeeeee..hhhhhhhhhhhhhhh...eeeeeeeee............eeee.........eeeeeeeee..hhhhhhhhhhhhh....eeeeeeeee.hhhh.......eeeee.....ee...............eeeehhhhhhhhhhhh-------h Sec.struct. author
                 SAPs(SNPs) --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- SAPs(SNPs)
                    PROSITE --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- PROSITE
                 Transcript --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Transcript
                 1i0i B   5 YEFAEKILFTEEEIRTRIKEVAKRIADDYKGKGLRPYVNPLVLISVLKGSFMFTADLCRALCDFNVPVRMEFICVSSYGEGLTSSGQVRMLLDTRHSIEGHHVLIVEDIVQTALTLNYLYHMYFTRRPASLKTVVLLDKREGRRVPFSADYVVANIPNAFVIGYGLDYDDTYRELRDIVVLRPEVYAEREAAR-------G 198
                                    14        24        34        44        54        64        74        84        94       104       114       124       134       144       154       164       174       184       194  |      -|
                                                                                                                                                                                                                          197     198
   Legend:   → Mismatch (orange background)
  - → Gap (green background, '-', border residues have a numbering label)
    → Modified Residue (blue background, lower-case, 'x' indicates undefined single-letter code, labelled with number + name)
  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, 2)

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

(-) CATH Domains  (1, 2)

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

(-) Pfam Domains  (0, 0)

(no "Pfam Domain" information available for 1I0I)

(-) Gene Ontology  (7, 13)

Asymmetric/Biological Unit(hide GO term definitions)
Chain A,B   (Q4DRC4_TRYCC | Q4DRC4)
molecular function
    GO:0004422    hypoxanthine phosphoribosyltransferase activity    Catalysis of the reaction: IMP + diphosphate = hypoxanthine + 5-phospho-alpha-D-ribose 1-diphosphate.
    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).
biological process
    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.

Chain A,B   (Q27796_TRYCR | Q27796)
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: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).
biological process
    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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 Related Entries

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

UniProtKB/Swiss-Prot
        Q27796_TRYCR | Q27796: 1i0l 1i13 1i14 1p17 1p18 1p19 1tc1 1tc2
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        Q4DRC4_TRYCC | Q4DRC4: 1i0l 1i13 1i14 1p17 1p18 1p19 1tc1 1tc2 5euc

(-) Related Entries Specified in the PDB File

1i0l ANALYSIS OF AN INVARIANT ASPARTIC ACID IN HPRTS - ASPARAGINE MUTANT
1i13 ANALYSIS OF AN INVARIANT ASPARTIC ACID IN HPRTS - ALANINE MUTANT
1i14 ANALYSIS OF AN INVARIANT ASPARTIC ACID IN HPRTS - GLUTAMIC ACID MUTANT
1tc1 ORIGINAL STRUCTURE OF THE WILD TYPE HPRT FROM TRYPANOSOMA CRUZI
1tc2 TERNARY SUBSTRATES COMPLEX OF THE WILD TYPE HPRT FROM TRYPANOSOMA CRUZI