G.P.S. Raghava
Understanding immune system
Breaking complex problem
Adaptive immunity
Innate Immunity
Vaccine delivery system
ADMET of peptides
Annotation of genomes
Searching drug targets
Properties of drug molecules
Protein-chemical interaction
Prediction of drug-like molecules
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Adaptive Immunity
Innate Immunity
WHOLE
ORGANISM
Bioinformatics Centre
IMTECH, Chandigarh
Purified Antigen
Protective Antigens
Vaccine Delivery
Epitopes (Subunit
Vaccine)
T cell epitope
Attenuated
Limitations of methods of subunit vaccine design
– Methods for one or two MHC alleles
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Do not consider pathways of antigen processing
– Limited to T-cell epitopes
Initiatives taken by our group
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Understand complete mechanism of antigen processing
– Develop better and comprehensive methods
– Promiscuous MHC binders 2
Adaptive Immunity
Innate Immunity
Disease Causing
Agents
Bioinformatics Centre
IMTECH, Chandigarh
Protective Antigens
Vaccine Delivery
3
Pathogens/Invaders
Adaptive Immunity
Innate Immunity
Protective Antigens
Vaccine Delivery
ER
TAP
Prediction of CTL Epitopes (Cell-mediated immunity)
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Adaptive Immunity
Innate Immunity
Protective Antigens
Vaccine Delivery
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Adaptive Immunity
Innate Immunity
MHCBN: A database of MHC/TAP binders and T-cell epitopes
Distributed by EBI, UK
Reference database in T-cell epitopes
Highly Cited ( ~ 70 citations)
Bhasin et al. (2003) Bioinformatics 19: 665
Bhasin et al. (2004) NAR (Online)
Protective Antigens
Vaccine Delivery
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Adaptive Immunity
Innate Immunity
Protective Antigens
Vaccine Delivery
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Prediction of MHC II Epitopes ( T helper
Epitopes)
Propred: Promiscuous of binders for 51 MHC Class II binders
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Virtual matrices
– Singh and Raghava (2001) Bioinformatics 17:1236
HLADR4pred : Prediction of HLA-DRB1*0401 binding peptides
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Dominating MHC class II allele
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ANN and SVM techniques
– Bhasin and Raghava (2004) Bioinformatics 12:421.
MHC2Pred: Prediction of MHC class II binders for 41 alleles
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Human and mouse
– Support vector machine (SVM) technique
– Extension of HLADR4pred
MMBpred : Prediction pf Mutated MHC Binder
– Mutations required to increase affinity
– Mutation required for make a binder promiscuous
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Bhasin and Raghava (2003) Hybrid Hybridomics, 22:229
MOT : Matrix optimization technique for binding core
MHCBench: Benchmarting of methods for MHC binders
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Adaptive Immunity
Innate Immunity
Protective Antigens
Vaccine Delivery
Propred1 : Promiscuous binders for 47 MHC class I alleles
– Cleavage site at C-terminal
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Singh and Raghava (2003) Bioinformatics 19:1109 nHLApred: Promiscuous binders for 67 alleles using ANN and QM
– Bhasin and Raghava (2007) J. Biosci. 32:31-42
TAPpred: Analysis and prediction of TAP binders
– Bhasin and Raghava (2004) Protein Science 13:596
Pcleavage : Proteasome and Immuno-proteasome cleavage site.
– Trained and test on in vitro and in vivo data
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Bhasin and Raghava (2005) Nucleic Acids Research 33: W202-7
CTLpred: Direct method for Predicting CTL Epitopes
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Bhasin and Raghava (2004) Vaccine 22:3195 8
Adaptive Immunity
Innate Immunity
Protective Antigens
Vaccine Delivery
9
Adaptive Immunity
Innate Immunity
BCIPEP: A database of
B-cell epitopes.
Saha et al.(2005) BMC Genomics 6:79.
Saha et al. (2006) NAR (Online)
Protective Antigens
Vaccine Delivery
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Adaptive Immunity
Innate Immunity
Protective Antigens
Vaccine Delivery
Prediction of B-Cell Epitopes
• BCEpred: Prediction of Continuous B-cell epitopes
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Benchmarking of existing methods
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Evaluation of Physico-chemical properties
– Poor performance slightly better than random
– Combine all properties and achieve accuracy around 58%
– Saha and Raghava (2004) ICARIS 197-204.
• ABCpred: ANN based method for B-cell epitope prediction
– Extract all epitopes from BCIPEP (around 2400)
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700 non-redundant epitopes used for testing and training
– Recurrent neural network
– Accuracy 66% achieved
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Saha and Raghava (2006) Proteins,65:40-48
• ALGpred: Mapping and Prediction of Allergenic Epitopes
– Allergenic proteins
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IgE epitope and mapping
– Saha and Raghava (2006) Nucleic Acids Research 34:W202-W209 11
Adaptive Immunity
Innate Immunity
Protective Antigens
Vaccine Delivery
HaptenDB: A database of hapten molecules
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Adaptive Immunity
Innate Immunity
Bioinformatics Centre
IMTECH, Chandigarh
PRRDB is a database of pattern recognition receptors and their ligands
~500 Pattern-recognition Receptors
228 ligands (PAMPs)
77 distinct organisms
720 entries
Protective Antigens
Vaccine Delivery
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Adaptive Immunity
Innate Immunity
Bioinformatics Centre
IMTECH, Chandigarh
Protective Antigens
Vaccine Delivery
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Adaptive Immunity
Innate Immunity
Bioinformatics Centre
IMTECH, Chandigarh
Major Challenges in Vaccine Design
•
ADMET of peptides and proteins
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Activate innate and adaptive immunity
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Prediction of carrier molecules
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Avoid cross reactivity (autoimmunity)
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Prediction of allergic epitopes
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Solubility and degradability
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Absorption and distribution
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Glycocylated epitopes
Protective Antigens
Vaccine Delivery
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Searching and analyzing druggable targets
Nucleotide
Genome
Annotation
Proteome
Annotation
Protein
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
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Searching and analyzing druggable targets
Nucleotide
Genome
Annotation
Proteome
Annotation
Protein
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
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FTGpred: Prediction of Prokaryotic genes
– Ab initio method for gene prediction using FFT technique
– Issac et al. (2002) Bioinformatics 18:197
EGpred: Prediction of eukaryotic genes
– BLASTX against RefSeq & BLASTN against intron database
– NNSPLICE program is used to reassign splicing signal site positions
– Issac and Raghava (2004) Genome Research 14:1756
GeneBench: Benchmarking of gene finders
– Collection of different datasets
– Tools for evaluating a method
– Creation of own datasets
SRF: Spectral Repeat finder
– FFT based repeat finder
– Sharma et al. (2004) Bioinformatics 20: 1405
Work in Progress
Prediction of polyadenylation signal (PAS) in human coding DNA
Understanding DICER cutter sites and siRNA/miRNA efficacy
Predict transcription factor binding sites in DNA sequences
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Searching and analyzing druggable targets
Nucleotide
Genome
Annotation
Proteome
Annotation
Protein
Protein
Struct.
Target
Proteins
Comparative genomics
GWFASTA: Genome Wide FASTA
Search
– Analysis of FASTA search for comparative genomics
– Biotechniques 2002, 33:548
Drug
Informatics
GWBLAST: Genome wide BLAST search
COPID: Composition based similarity search
LGEpred: Expression of a gene from its Amino acid sequence
– BMC Bioinformatics 2005, 6:59
ECGpred: Expression from its nucleotide sequence
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
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Searching and analyzing druggable targets
Nucleotide Protein
Genome
Annotation
Proteome
Annotation
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
Subcellular localization Methods
PSLpred: Subcellular localization of prokaryotic proteins
– 5 major sub cellular localization
– Bioinformatics 2005, 21: 2522
ESLpred: Subcellular localization of Eukaryotic proteins
– SVM based method
– Amino acid, Dipetide and properties composition
– Sequence profile (PSIBLAST)
– Nucleic Acids Research 2004, 32:W414-9
HSLpred : Sub cellular localization of Human proteins
– Need to develop organism specific methods
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84% accuracy for human proteins
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Journal of Biological Chemistry 2005, 280:14427-32
MITpred: Prediction of Mitochndrial proteins
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Exclusive mitochndrial domain and SVM
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J Biol Chem. 2005, 281:5357-63.
Work in Progress: Subcellular localization of M.Tb. and malaria
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Searching and analyzing druggable targets
Nucleotide
Genome
Annotation
Proteome
Annotation
Protein
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
Regular Secondary Structure Prediction (
-helix
-sheet)
• APSSP2: Highly accurate method for secondary structure prediction
Competete in EVA, CAFASP and CASP (In top 5 methods)
Irregular secondary structure prediction methods (Tight turns)
• Betatpred : Consensus method for
-turns prediction
– Statistical methods combined
– Kaur and Raghava (2001) Bioinformatics
• Bteval : Benchmarking of
-turns prediction
– Kaur and Raghava (2002) J. Bioinformatics and Computational Biology, 1:495:504
• BetaTpred2 : Highly accurate method for predicting
-turns (ANN, SS, MA)
– Multiple alignment and secondary structure information
– Kaur and Raghava (2003) Protein Sci 12:627-34
• BetaTurns : Prediction of
-turn types in proteins
– Kaur and Raghava (2004) Bioinformatics 20:2751-8.
• AlphaPred : Prediction of
-turns in proteins
– Kaur and Raghava (2004) Proteins: Structure, Function, and Genetics 55:83-90
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GammaPred : Prediction of
-turns in proteins
– Kaur and Raghava (2004) Protein Science; 12:923-929 .
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Searching and analyzing druggable targets
Nucleotide
Genome
Annotation
Proteome
Annotation
Protein
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
Supersecondary Structure
BhairPred : Prediction of Beta Hairpins
– Secondary structure and surface accessibility used as input
– Manish et al. (2005) Nucleic Acids Research 33:W154-9
TBBpred: Prediction of outer membrane proteins
– Prediction of trans membrane beta barrel proteins
– Application of ANN and SVM + Evolutionary information
– Natt et al. (2004) Proteins: 56:11-8
ARNHpred: Analysis and prediction side chain, backbone interactions
– Prediction of aromatic NH interactions
– Kaur and Raghava (2004) FEBS Letters 564:47-57 .
Chpredict : Prediction of C-H .. O and PI interaction
– Kaur and Raghava (2006) In-Silico Biology 6:0011
SARpred : Prediction of surface accessibility (real accessibility)
– Multiple alignment (PSIBLAST) and Secondary structure information
– Garg et al., (2005) Proteins 61:318-24
Secondary to Tertiary Structure
PepStr : Prediction of tertiary structure of Bioactive peptides
– Kaur et al. (2007) Protein Pept Lett. (In Press)
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Searching and analyzing druggable targets
Nucleotide Protein
Genome
Annotation
Proteome
Annotation
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
23
Searching and analyzing druggable targets
Nucleotide Protein
Genome
Annotation
Proteome
Annotation
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
Nrpred : Classification of nuclear receptors
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BLAST fails in classification of NR proteins
– Uses composition of amino acids
Journal of Biological Chemistry 2004, 279: 23262
GPCRpred : Prediction of G-protein-coupled receptors
– Predict GPCR proteins & class
– > 80% in Class A, further classify
Nucleic Acids Research 2004, 32:W383
GPCRsclass : Amine type of GPCR
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Major drug targets, 4 classes,
– Accuracy 96.4%
Nucleic Acids Research 2005, 33:W172
VGIchan: Voltage gated ion channel
– Genomics Proteomics & Bioinformatics 2007, 4:253-8
Pprint: RNA interacting residues in proteins
– Proteins: Structure, Function and Bioinformatics (In Press)
GSTpred: Glutathione S-transferases proteins
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Protein Pept Lett. 2007, 6:575-80
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Searching and analyzing druggable targets
Nucleotide
Genome
Annotation
Proteome
Annotation
Protein
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
Antibp: Analysis and prediction of antibacterial peptides
• Searching and mapping of antibacterial peptide
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BMC Bioinformatics 2007, 8:263
ALGpred: Prediction of allergens
•Using allergen representative peptides
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Nucleic Acids Research 2006, 34:W202-9.
BTXpred: Prediction of bacterial toxins
•Classifcation of toxins into exotoxins and endotoxins
•Classification of exotoxins in seven classes
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In Silico Biology 2007, 7: 0028
• NTXpred: Prediction of neurotoxins
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Classification based on source
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Classification based on function (ion channel blockers, blocks
Acetylcholine receptors etc.)
• In Silico Biology 2007, 7, 0025
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Searching and analyzing druggable targets
Nucleotide
Genome
Annotation
Proteome
Annotation
Protein
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
1. Prediction of solubility of proteins and peptides
2. Understand drug delivery system for protein
3. Degradation of proteins
4. Improving thermal stability of a protein ( Protein
Science 12:2118-2120 )
5. Analysis and prediction of druggable proteins/peptide
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Searching and analyzing druggable targets
Nucleotide
Genome
Annotation
Proteome
Annotation
Protein
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
MELTpred: Prediction of melting point of chemical compunds
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Around 4300 compounds were analzed to derive rules
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Successful predicted melting point of 277 drug-like molecules
1. QSAR models for ADMET
2. QSAR + docking for ADMET
3. Prediction of drug like molecules
4. Open access in Chemoinformatics
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Searching and analyzing druggable targets
Nucleotide Protein
Genome
Annotation
Proteome
Annotation
Protein
Struct.
Target
Proteins
Drug
Informatics
Prediction and analysis of drug molecules
Biologicals
Protein
Chemical s
Protein-drug
Drugs
Interaction
Drug-like
Molecules
Understanding Protein-Chemical Interaction
Prediction of Kinases Targets and Off Targets
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Kinases inhibitors were analyzed
• Model build to predict inhbitor against kinases
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Cross-Specificity were checked
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Useful for predicting targets and off targets
• Classification of proteins based on chemical interaction
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Clustering drug molecules based on interaction with proteins
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