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MSD motif www.ebi.ac.uk/msd-srv/msdmotif. Structure Annotation and Function Assignment with MSDmotif. PDB: 1gci. MSDmotif front options. Small motifs. Alpha-Beta Motif. Nest. ST staple. 11 motifs in total Prof James Milner-White. Small motif stats. Occurrence of amino-acids.
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MSD motifwww.ebi.ac.uk/msd-srv/msdmotif Structure Annotation and Function Assignment with MSDmotif PDB: 1gci
Small motifs Alpha-Beta Motif Nest ST staple 11 motifs in total Prof James Milner-White
Small motif stats Occurrence of amino-acids Correlation of side chain charge
Small motifs – 3D alignment ST-staple
Small motifs viewing Ligands Catalytic sites ProSite Small motifs “Group” menu item contains a list of presented in a PDB entry sites and motifs
, search PDB:1gci Ideal for short loops search
, search - continue PDB:1gci Subtilases family PDB:1f5p Globins family
, search vs sequence search Sequences found while search by , : Subtilases family NNSIGVL DNTTGVL DNSIGVL Globins family IVDTGSV Blast search for NNSIGVL Diphtheria toxin family SDSIGVL
3D motif research Asx turn PDB 1e4m has the small motif - Asx turn of residues 65-67 (ASP-HIS-GLY), which is found in a loop between two helixes Use phi/psi parameters of these three residues for a search
3D motif research - continue • The sequences from the hit list: • LKY • QGF • DRF • AGV • RGV • DHG • MGK • DNL • HGV • ANN • TGA • QCY • LGA • NSY Most of these hits were found in loops between helixes
Pattern search ZN binding pattern: CXXCXXXFXXXXXLXXHXXXH
Sequence search • Pseudo multiple sequence alignment (blast output based) • Ligand binding residues are marked • Normalization of hit list to 50% sequence identity
Helper application for multiple sequences alignment Blixem as helper browser application for multiple sequences alignment based on blast output Mime-type: application/x-blast Blixem http://www.cgb.ki.se/cgb/groups/sonnhammer/Blixem.html
Helper application for multiple sequences alignment Jalview as helper browser application for sequences alignment Mime-type: application/x-align http://www.jalview.org/ Alignment of Zinc binding PROSITE patter hits
Sequence hits 3D alignment 2 hits with less than 25% sequence identity Fragments alignment Chains alignment
Secondary structure patterns Strand – turn – Strand 2-3 residues gap Glycosylation pattern N{P}[ST]{P} Where N binds sugar: Man or Nag
MSD motif Small 3D motifs from J.Milner-White search/view Secondary structure patterns (HTH) search/view ,, based search/view Ligands and their environment search/view Catalytic sites search/view Blast sequence search/view PROSITE format compliant patterns search/view 3D and sequence multiple alignment Hit list and statistics normalization by SCOP,CATH
MSDmotif as web service XML respond as eFamily XML MSDmotif server XML query www.eFamily.org.uk Hydrogen bonds ,, angles Secondary structures + small motifs Secondary structure patterns Sequence patterns Blast sequences Prosite, Catalytic sites, Merops Ligands, fragments, SMILEs Ligand interactions Arithmetic operations XML query
XML query example Task: Find PDB entries where a ligand is capping a helix and at the same time binds its N-termini. <?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE query …>- <query useUndefinedBonds="yes" phipsiDeviation="10" eValue="auto">- <declaration> <ligand>x l</ligand> <ss>H h</ss> </declaration> <interaction>l.[O]<->h.first.N=H</interaction> <interaction>l.[O]<->h.last.N<3.5</interaction> </query>
Extending eFamily XML Helix Strand Beta-turn Gamma-turn Alpha-beta-motif Asx-turn ST-turn ST-staple … Chain Bound-molecule Water-group segment entry pdb-entry entity Standard ways of extending an XML schema: - extension - restriction - substitution group
MSD motif • www.ebi.ac.uk/msd-srv/msdmotif • 32000 PDBs, 25 G disk space on Oracle DB, linear dependency ~ 0.8 M per PDB • Web application server with J2EE servlet engine • NCBI Blast for sequence search
MSDmotif future development • 3D alignment extension • Water interactions • Statistical analysis and presentation • Secondary structure patterns • Statistics from MSDmotif hit list • Correlation of different parameters like residues weight, csi/phi/psi angles. • Neural network for recognition of complex structure fragments/motifs in a PDB and their function association