Emaill.a.kelley@imperial.ac.uk
DescriptionP0A7E3
DateThu Jan 5 11:05:28 GMT 2012
Unique Job IDf8d344792be175bc

Detailed template information 

#Template Alignment Coverage3D Model Confidence% i.d. Template Information
1d1lh0a_



100.0 97 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
2c3n2lA_



100.0 80 PDB header:transferase
Chain: A: PDB Molecule:orotate phosphoribosyltransferase;
PDBTitle: 2.1 angstrom resolution crystal structure of an orotate2 phosphoribosyltransferase (pyre) from vibrio cholerae o1 biovar eltor3 str. n16961
3c2przB_



100.0 47 PDB header:transferase
Chain: B: PDB Molecule:orotate phosphoribosyltransferase 1;
PDBTitle: s. cerevisiae orotate phosphoribosyltransferase complexed2 with omp
4c3mjdA_



100.0 45 PDB header:transferase
Chain: A: PDB Molecule:orotate phosphoribosyltransferase;
PDBTitle: 1.9 angstrom crystal structure of orotate2 phosphoribosyltransferase (pyre) francisella tularensis.
5c2wnsB_



100.0 28 PDB header:transferase
Chain: B: PDB Molecule:orotate phosphoribosyltransferase;
PDBTitle: human orotate phosphoribosyltransferase (oprtase) domain of2 uridine 5'-monophosphate synthase (umps) in complex with3 its substrate orotidine 5'-monophosphate (omp)
6c3qw4B_



100.0 24 PDB header:transferase, lyase
Chain: B: PDB Molecule:ump synthase;
PDBTitle: structure of leishmania donovani ump synthase
7c3dezA_



100.0 18 PDB header:transferase
Chain: A: PDB Molecule:orotate phosphoribosyltransferase;
PDBTitle: crystal structure of orotate phosphoribosyltransferase from2 streptococcus mutans
8d2aeea1



100.0 22 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
9c3m3hA_



100.0 21 PDB header:transferase
Chain: A: PDB Molecule:orotate phosphoribosyltransferase;
PDBTitle: 1.75 angstrom resolution crystal structure of an orotate2 phosphoribosyltransferase from bacillus anthracis str. 'ames3 ancestor'
10c2yzkC_



100.0 27 PDB header:transferase
Chain: C: PDB Molecule:orotate phosphoribosyltransferase;
PDBTitle: crystal structure of orotate phosphoribosyltransferase from2 aeropyrum pernix
11d1mzva_



100.0 20 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
12c2p1zA_



100.0 20 PDB header:transferase
Chain: A: PDB Molecule:phosphoribosyltransferase;
PDBTitle: crystal structure of phosphoribosyltransferase from corynebacterium2 diphtheriae
13d1qb7a_



100.0 19 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
14d1y0ba1



100.0 20 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
15d1o57a2



99.9 21 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
16c2dy0A_



99.9 19 PDB header:transferase
Chain: A: PDB Molecule:adenine phosphoribosyltransferase;
PDBTitle: crystal structure of project jw0458 from escherichia coli
17c1o57A_



99.9 19 PDB header:dna binding protein
Chain: A: PDB Molecule:pur operon repressor;
PDBTitle: crystal structure of the purine operon repressor of2 bacillus subtilis
18d1zn7a1



99.9 19 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
19d1l1qa_



99.9 18 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
20d1g2qa_



99.9 23 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
21d1vcha1



not modelled 99.8 23 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
22d1vdma1



not modelled 99.8 19 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
23d2igba1



not modelled 99.8 19 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
24d1ufra_



not modelled 99.7 20 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
25d1hgxa_



not modelled 99.7 15 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
26d1w30a_



not modelled 99.7 17 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
27c3o7mD_



not modelled 99.7 11 PDB header:transferase
Chain: D: PDB Molecule:hypoxanthine phosphoribosyltransferase;
PDBTitle: 1.98 angstrom resolution crystal structure of a hypoxanthine-guanine2 phosphoribosyltransferase (hpt-2) from bacillus anthracis str. 'ames3 ancestor'
28d1a3ca_



not modelled 99.7 17 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
29d1g9sa_



not modelled 99.7 13 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
30c2ywtA_



not modelled 99.7 12 PDB header:transferase
Chain: A: PDB Molecule:hypoxanthine-guanine phosphoribosyltransferase;
PDBTitle: crystal structure of hypoxanthine-guanine2 phosphoribosyltransferase with gmp from thermus3 thermophilus hb8
31d1j7ja_



not modelled 99.7 12 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
32d1z7ga1



not modelled 99.7 12 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
33d1pzma_



not modelled 99.7 15 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
34d1tc1a_



not modelled 99.7 13 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
35c3kb8A_



not modelled 99.7 14 PDB header:transferase
Chain: A: PDB Molecule:hypoxanthine phosphoribosyltransferase;
PDBTitle: 2.09 angstrom resolution structure of a hypoxanthine-guanine2 phosphoribosyltransferase (hpt-1) from bacillus anthracis str. 'ames3 ancestor' in complex with gmp
36c1pzmB_



not modelled 99.6 13 PDB header:transferase
Chain: B: PDB Molecule:hypoxanthine-guanine phosphoribosyltransferase;
PDBTitle: crystal structure of hgprt-ase from leishmania tarentolae in complex2 with gmp
37d1yfza1



not modelled 99.6 18 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
38c1yfzA_



not modelled 99.6 18 PDB header:transferase
Chain: A: PDB Molecule:hypoxanthine-guanine phosphoribosyltransferase;
PDBTitle: novel imp binding in feedback inhibition of hypoxanthine-guanine2 phosphoribosyltransferase from thermoanaerobacter tengcongensis
39d1p17b_



not modelled 99.6 13 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
40c2jkzB_



not modelled 99.6 16 PDB header:transferase
Chain: B: PDB Molecule:hypoxanthine-guanine phosphoribosyltransferase;
PDBTitle: saccharomyces cerevisiae hypoxanthine-guanine2 phosphoribosyltransferase in complex with gmp (guanosine 5'3 -monophosphate) (orthorhombic crystal form)
41d1ecfa1



not modelled 99.5 17 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
42d1nula_



not modelled 99.5 13 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
43d1gph11



not modelled 99.5 25 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
44c2jbhA_



not modelled 99.5 12 PDB header:transferase
Chain: A: PDB Molecule:phosphoribosyltransferase domain-containing protein 1;
PDBTitle: human phosphoribosyl transferase domain containing 1
45c3lpnB_



not modelled 99.5 18 PDB header:transferase
Chain: B: PDB Molecule:ribose-phosphate pyrophosphokinase;
PDBTitle: crystal structure of the phosphoribosylpyrophosphate (prpp) synthetase2 from thermoplasma volcanium in complex with an atp analog (ampcpp).
46c1ecjB_



not modelled 99.4 17 PDB header:transferase
Chain: B: PDB Molecule:glutamine phosphoribosylpyrophosphate
PDBTitle: escherichia coli glutamine phosphoribosylpyrophosphate2 (prpp) amidotransferase complexed with 2 amp per tetramer
47d1wd5a_



not modelled 99.4 24 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
48c3efhB_



not modelled 99.4 17 PDB header:transferase
Chain: B: PDB Molecule:ribose-phosphate pyrophosphokinase 1;
PDBTitle: crystal structure of human phosphoribosyl pyrophosphate2 synthetase 1
49d1fsga_



not modelled 99.4 13 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
50d1cjba_



not modelled 99.4 11 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
51c1gph1_



not modelled 99.4 26 PDB header:transferase(glutamine amidotransferase)
Chain: 1: PDB Molecule:glutamine phosphoribosyl-pyrophosphate amidotransferase;
PDBTitle: structure of the allosteric regulatory enzyme of purine biosynthesis
52c1dkrB_



not modelled 99.3 22 PDB header:transferase
Chain: B: PDB Molecule:phosphoribosyl pyrophosphate synthetase;
PDBTitle: crystal structures of bacillus subtilis phosphoribosylpyrophosphate2 synthetase: molecular basis of allosteric inhibition and activation.
53c2c4kD_



not modelled 99.2 17 PDB header:regulatory protein
Chain: D: PDB Molecule:phosphoribosyl pyrophosphate synthetase-
PDBTitle: crystal structure of human phosphoribosylpyrophosphate2 synthetase-associated protein 39 (pap39)
54d1dkua2



not modelled 99.2 24 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosylpyrophosphate synthetase-like
55d1u9ya2



not modelled 99.2 21 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosylpyrophosphate synthetase-like
56d2c4ka2



not modelled 99.2 22 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosylpyrophosphate synthetase-like
57c1u9yD_



not modelled 99.1 21 PDB header:transferase
Chain: D: PDB Molecule:ribose-phosphate pyrophosphokinase;
PDBTitle: crystal structure of phosphoribosyl diphosphate synthase2 from methanocaldococcus jannaschii
58c3dahB_



not modelled 98.9 16 PDB header:transferase
Chain: B: PDB Molecule:ribose-phosphate pyrophosphokinase;
PDBTitle: 2.3 a crystal structure of ribose-phosphate pyrophosphokinase from2 burkholderia pseudomallei
59d1dqna_



not modelled 98.3 17 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
60c2ehjA_



not modelled 98.3 12 PDB header:transferase
Chain: A: PDB Molecule:uracil phosphoribosyltransferase;
PDBTitle: structure of uracil phosphoribosyl transferase
61d1o5oa_



not modelled 98.2 15 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
62c2e55D_



not modelled 98.2 9 PDB header:transferase
Chain: D: PDB Molecule:uracil phosphoribosyltransferase;
PDBTitle: structure of aq2163 protein from aquifex aeolicus
63d1i5ea_



not modelled 98.1 11 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
64d1xtta1



not modelled 97.7 9 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
65d1bd3a_



not modelled 97.7 13 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
66c3dmpD_



not modelled 97.6 10 PDB header:transferase
Chain: D: PDB Molecule:uracil phosphoribosyltransferase;
PDBTitle: 2.6 a crystal structure of uracil phosphoribosyltransferase2 from burkholderia pseudomallei
67d1v9sa1



not modelled 97.4 14 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosyltransferases (PRTases)
68d1g57a_



not modelled 91.5 25 Fold:YrdC/RibB
Superfamily:YrdC/RibB
Family:3,4-dihydroxy-2-butanone 4-phosphate synthase, DHBP synthase, RibB
69d1tksa_



not modelled 90.8 14 Fold:YrdC/RibB
Superfamily:YrdC/RibB
Family:3,4-dihydroxy-2-butanone 4-phosphate synthase, DHBP synthase, RibB
70d1snna_



not modelled 89.5 8 Fold:YrdC/RibB
Superfamily:YrdC/RibB
Family:3,4-dihydroxy-2-butanone 4-phosphate synthase, DHBP synthase, RibB
71c3mioA_



not modelled 89.3 15 PDB header:lyase
Chain: A: PDB Molecule:3,4-dihydroxy-2-butanone 4-phosphate synthase;
PDBTitle: crystal structure of 3,4-dihydroxy-2-butanone 4-phosphate synthase2 domain from mycobacterium tuberculosis at ph 6.00
72d1k4ia_



not modelled 83.5 20 Fold:YrdC/RibB
Superfamily:YrdC/RibB
Family:3,4-dihydroxy-2-butanone 4-phosphate synthase, DHBP synthase, RibB
73d1s8na_



not modelled 79.4 18 Fold:Flavodoxin-like
Superfamily:CheY-like
Family:CheY-related
74d1u9ya1



not modelled 69.7 11 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosylpyrophosphate synthetase-like
75c2vspA_



not modelled 62.3 15 PDB header:transport protein
Chain: A: PDB Molecule:pdz domain-containing protein 1;
PDBTitle: crystal structure of the fourth pdz domain of pdz domain-2 containing protein 1
76d1vaea_



not modelled 60.4 12 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
77c3l4fD_



not modelled 59.9 18 PDB header:signaling protein/protein binding
Chain: D: PDB Molecule:sh3 and multiple ankyrin repeat domains protein
PDBTitle: crystal structure of betapix coiled-coil domain and shank2 pdz complex
78c2vsvB_



not modelled 57.2 12 PDB header:protein-binding
Chain: B: PDB Molecule:rhophilin-2;
PDBTitle: crystal structure of the pdz domain of human rhophilin-2
79d2c4ka1



not modelled 57.1 11 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosylpyrophosphate synthetase-like
80d1m5za_



not modelled 54.8 23 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
81c3eggC_



not modelled 54.4 10 PDB header:hydrolase
Chain: C: PDB Molecule:spinophilin;
PDBTitle: crystal structure of a complex between protein phosphatase 1 alpha2 (pp1) and the pp1 binding and pdz domains of spinophilin
82c2d90A_



not modelled 54.1 15 PDB header:protein binding
Chain: A: PDB Molecule:pdz domain containing protein 1;
PDBTitle: solution structure of the third pdz domain of pdz domain2 containing protein 1
83c3r2uC_



not modelled 52.6 18 PDB header:hydrolase
Chain: C: PDB Molecule:metallo-beta-lactamase family protein;
PDBTitle: 2.1 angstrom resolution crystal structure of metallo-beta-lactamase2 from staphylococcus aureus subsp. aureus col
84c2jxoA_



not modelled 52.6 23 PDB header:protein binding
Chain: A: PDB Molecule:ezrin-radixin-moesin-binding phosphoprotein 50;
PDBTitle: structure of the second pdz domain of nherf-1
85c3mmnA_



not modelled 51.8 23 PDB header:transferase
Chain: A: PDB Molecule:histidine kinase homolog;
PDBTitle: crystal structure of the receiver domain of the histidine kinase cki12 from arabidopsis thaliana complexed with mg2+
86c1a2oB_



not modelled 51.5 20 PDB header:bacterial chemotaxis
Chain: B: PDB Molecule:cheb methylesterase;
PDBTitle: structural basis for methylesterase cheb regulation by a2 phosphorylation-activated domain
87d1q3oa_



not modelled 51.3 18 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
88c2o2tB_



not modelled 50.8 10 PDB header:structural protein
Chain: B: PDB Molecule:multiple pdz domain protein;
PDBTitle: the crystal structure of the 1st pdz domain of mpdz
89c3diwB_



not modelled 48.2 10 PDB header:signaling protein/cell adhesion
Chain: B: PDB Molecule:tax1-binding protein 3;
PDBTitle: c-terminal beta-catenin bound tip-1 structure
90c2kjdA_



not modelled 47.5 23 PDB header:signaling protein
Chain: A: PDB Molecule:sodium/hydrogen exchange regulatory cofactor nhe-
PDBTitle: solution structure of extended pdz2 domain from nherf1 (150-2 270)
91d1ihja_



not modelled 47.5 6 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
92c3qglD_



not modelled 47.2 20 PDB header:protein binding
Chain: D: PDB Molecule:sorting nexin-27;
PDBTitle: crystal structure of pdz domain of sorting nexin 27 (snx27) in complex2 with the eseskv peptide corresponding to the c-terminal tail of girk3
93c1r6jA_



not modelled 47.1 10 PDB header:membrane protein
Chain: A: PDB Molecule:syntenin 1;
PDBTitle: ultrahigh resolution crystal structure of syntenin pdz2
94d1r6ja_



not modelled 47.1 10 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
95c1nteA_



not modelled 47.1 10 PDB header:signaling protein
Chain: A: PDB Molecule:syntenin 1;
PDBTitle: crystal structure analysis of the second pdz domain of2 syntenin
96c1j6uA_



not modelled 46.6 11 PDB header:ligase
Chain: A: PDB Molecule:udp-n-acetylmuramate-alanine ligase murc;
PDBTitle: crystal structure of udp-n-acetylmuramate-alanine ligase2 murc (tm0231) from thermotoga maritima at 2.3 a resolution
97c2eeiA_



not modelled 46.2 15 PDB header:metal binding protein
Chain: A: PDB Molecule:pdz domain-containing protein 1;
PDBTitle: solution structure of second pdz domain of pdz domain2 containing protein 1
98c1obyA_



not modelled 46.0 10 PDB header:cell adhesion
Chain: A: PDB Molecule:syntenin 1;
PDBTitle: crystal structure of the complex of pdz2 of syntenin with2 a syndecan-4 peptide.
99d1dcfa_



not modelled 44.9 15 Fold:Flavodoxin-like
Superfamily:CheY-like
Family:Receiver domain of the ethylene receptor
100d1vi2a1



not modelled 44.2 17 Fold:NAD(P)-binding Rossmann-fold domains
Superfamily:NAD(P)-binding Rossmann-fold domains
Family:Aminoacid dehydrogenase-like, C-terminal domain
101d1dkua1



not modelled 44.2 11 Fold:PRTase-like
Superfamily:PRTase-like
Family:Phosphoribosylpyrophosphate synthetase-like
102c2kv8A_



not modelled 43.8 13 PDB header:signaling protein
Chain: A: PDB Molecule:regulator of g-protein signaling 12;
PDBTitle: solution structure ofrgs12 pdz domain
103c2he4A_



not modelled 43.7 20 PDB header:structural genomics, unknown function
Chain: A: PDB Molecule:na(+)/h(+) exchange regulatory cofactor nhe-rf2;
PDBTitle: the crystal structure of the second pdz domain of human2 nherf-2 (slc9a3r2) interacting with a mode 1 pdz binding3 motif
104c2z17A_



not modelled 43.5 19 PDB header:protein binding
Chain: A: PDB Molecule:pleckstrin homology sec7 and coiled-coil domains-
PDBTitle: crystal sturcture of pdz domain from human pleckstrin2 homology, sec7
105d1v6ba_



not modelled 43.0 18 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
106d2fe5a1



not modelled 40.6 8 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
107d1g9oa_



not modelled 40.6 13 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
108d1y7na1



not modelled 40.2 10 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
109c3k1rA_



not modelled 40.0 10 PDB header:structural protein
Chain: A: PDB Molecule:harmonin;
PDBTitle: structure of harmonin npdz1 in complex with the sam-pbm of2 sans
110c2edzA_



not modelled 40.0 15 PDB header:signaling protein
Chain: A: PDB Molecule:pdz domain-containing protein 1;
PDBTitle: solution structures of the pdz domain of mus musculus pdz2 domain-containing protein 1
111c2krgA_



not modelled 39.9 23 PDB header:signaling protein
Chain: A: PDB Molecule:na(+)/h(+) exchange regulatory cofactor nhe-rf1;
PDBTitle: solution structure of human sodium/ hydrogen exchange2 regulatory factor 1(150-358)
112c2pkuA_



not modelled 39.9 15 PDB header:protein binding
Chain: A: PDB Molecule:prkca-binding protein;
PDBTitle: solution structure of pick1 pdz in complex with the2 carboxyl tail peptide of glur2
113d1u3ba2



not modelled 39.8 11 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
114c2dmzA_



not modelled 39.7 20 PDB header:protein binding
Chain: A: PDB Molecule:inad-like protein;
PDBTitle: solution structure of the third pdz domain of human inad-2 like protein
115c1obyB_



not modelled 39.3 10 PDB header:cell adhesion
Chain: B: PDB Molecule:syntenin 1;
PDBTitle: crystal structure of the complex of pdz2 of syntenin with2 a syndecan-4 peptide.
116d1obxa_



not modelled 39.3 10 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
117c1obxA_



not modelled 39.3 10 PDB header:cell adhesion
Chain: A: PDB Molecule:syntenin 1;
PDBTitle: crystal structure of the complex of pdz2 of syntenin with2 an interleukin 5 receptor alpha peptide.
118d2j01f1



not modelled 38.9 13 Fold:Ribosomal protein L4
Superfamily:Ribosomal protein L4
Family:Ribosomal protein L4
119d1uita_



not modelled 38.1 10 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain
120d1wjla_



not modelled 38.1 21 Fold:PDZ domain-like
Superfamily:PDZ domain-like
Family:PDZ domain