RESEARCH ARTICLE. M. P Nithya, 1* T. Radha 1 and M. Balaji 2

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1 Available online at ISSN: INTERNATIONAL JOURNAL OF NOVEL TRENDS IN PHARMACEUTICAL SCIENCES Study of In Silico Drug Docking for Tegumental H17G Protein and Oncosphere TSO45-2A Protein in Taenia Solium (Linnaeus, 1758) using Bioinformatics Tools RESEARCH ARTICLE M. P Nithya, 1* T. Radha 1 and M. Balaji 2 1 Department of Advanced zoology and Biotechnology, Ethiraj College for Women (Autonomous) Chennai Tamil Nadu 2 Director, Akshaya Neuroinformatics Research center, Chennai Tamil Nadu Article Info Article history Received 20 May 2012 Revised 25 May 2012 Accepted 22 Jun 2012 Available online 30 Jun 2012 Keywords Parasitic Infections, Potential Targets Ch17 G Protein, Tegumental Antigen, Automated Docking Server. Abstract Parasitic infections are most common now-a-days which arise as a global problem. Inflammation is due to the human s immune system response to the dying cysts. Antibiotics such as Mebandazole and Albendazole have been found effective against these infections. The current work focuses on structure based drug designing against potential targets of parasitic infections. AIM: The main aim of present investigation is the comparative modeling and ligand designing of potential targets CH17 g protein, tegumental antigen and activated onchosphere which are threats to both taeniasis and cysticerosis. METHODS: Software tools were used to detect the tertiary structure of target and protein modeling were done using swiss-model server. The appropriate ligands of the potential targets were selected using pubchem compound database. The behavior of these ligands was analysed using molecular visualization tool. RESULTS/DISCUSSION: The designed ligands were validated and their binding affinities were analysed. The designed ligands Albendazole with Benzoate and Albendazole with Methythiodiocarbomate and receptors, namely, H17g protein, tegumental antigen and activated oncosphere TSO45-2A are docked using automated docking server. From the results obtained, it is deduced that combined ligands (Albendazole with Benzoate and Albendazole with Methythiodiocarbomate) are better binding drug targets than just the albendazole ligand. CONCLUSION: These drugs can be very effective against destruction of parasitic worms. Hence, they can be used therapeutically in the treatment of Helminthiasis in man and animal. INTRODUCTION Veterinary parasitology has traditionally been concerned with the control of parasites of livestock and companion animals, with emphasis on chemotherapy and immunoprophylaxis. 1 One phase the parasite and hostrelationship among the cestodes that concern humans and domestic animals, is that the parasites cause varying degrees of pathogenic alternations. They are, therefore of great interest to the medical and veterinary professions. 2. Taenia solium taeniasis and cysticercosis are diseases rooted in developing countries, but gaining more importance as a global problem,3 Taeniasis is a tapeworm (Cestode) infection acquired by the ingestion of raw or undercooked meat of infected animals. Although many species exist, two species, Taenia saginata and Taenia solium, cause pathology in H humans. T. saginata is associated with the ingestion of the worm's larval form found in infected beef while T. solium is associated with that of infected pork. T. saginata is also commonly known as beef tapeworm. T. solium is similarly referred to as pork tapeworm. Both species are worldwide in distribution-- approximately 100 million cases of infection world-wide annually. Approximately 50 million cases of these cases are T. saginata while the other 50 million are T. solium related. T.solium is found worldwide, however, it has shown to be more common in cosmopolitan areas. Because pigs To whom correspondence should be addressed: M.P. Nithya address: nithya.mp@gmail.com VOLUME 2 NUMBER 2 JUN

2 are intermediate hosts of the parasite, completion of the life cycle occurs in regions where humans live in close contact with pigs and eat undercooked pork. The area most affected by taeniasis currently is Indonesia the western half of New Guinea Island, India, Southeast Asia and China. In field surveys conducted in 2000 and 2001, researchers found that 5 (8.6%) of 58 local people and 7 (11%) of 64 local dogs living approximately 1 km from the local capital city, Wamena, in Jayawijaya District, harbored adult tapeworms and cysticerci of Taenia solium. Due to the prevalence of this tapeworm worldwide and increasing immigration and foreign travel, Taenia solium will likely continue to emerge as an important pathogen in the United States. 4 One of the most promising developments evolved from the study of human genes and proteins has been the identification of potential new drugs for the treatment of disease. It relies on genome and proteome information to identify protein associated with a taeniasis/cysticercosis disease, which computer software can then use it as target for new drug development. Assuming H17g protein, tegumental antigen and Activated oncosphere TSO 45-2A protein involved in a taeniasis/cysticercosis, their 3D structure may provide information to design new drugs. These drugs will fit to the active sites of the target protein molecules and interfere with mode of action of these proteins. PZQ (praziquantel) is the drug of choice for the treatment of T. solium infection. Some considerniclosamide to be the drug of choice for all types of Tapeworms. [5] For cysticercosis, one can be treated with albendazole combining with steroid to reduce the inflammation. Surgical intervention may be necessary to treat CNS lesions. Albendazole appears to be more effective and a safe drug forneurocysticercosis, infection of the brain with T. solium larvae. [6][7] T. solium is found worldwide, however, it has shown to be more common in cosmopolitan areas. Because pigs are intermediate hosts of the parasite, completion of the life cycleoccurs in regions where humans live in close contact with pigs and eat undercooked pork. Cysticercosis is often seen in areas where poor hygiene allows for contamination of food, soil or water supplies. Prevalence rates in the United States have shown that immigrants frommexico, Central and South America and South-east Asia account for most of the domestic cases of cysticercosis. [8] Taeniasis and cysticercosis are very rare in predominantly Muslimcountries, as Islam forbids the consumption of pork. It is important to note that human cysticercosis is acquired by ingesting T. solium eggs shed in the feces of a human tapeworm carrier via gravid proglottids, and thus can occur in populations that neither eat pork nor share environments with pigs, although, as stated, the completion of the life cyclecan occur only where humans live in close contact with pigs and eat pork. In 1990 and 1991, four unrelated members of an Orthodox Jewish community in New York City developed recurrent seizures and brain lesions which were found to have been caused by cysticercosis from T. solium. In keeping with their religion, none of the patients ate pork; additionally, none had any history of recent foreign travel. Several immediate family members of these four patients with seizures were found to have cysticercus antibodies. The families of the four patients had all employed housekeepers from Latin American countries, and one of the housekeepers tested positive for cysticercus antibodies, leading to the conclusion that the housekeepers were the most likely source of the infections. [9][10] AIM AND OBJECTIVES To find out the potential protein in Helminthiasis diseases using literature databases.to access protein function.to predict 3D structure of the protein.to visualize the protein model.to validate the structure of protein.to design the ligands.to dock the ligands with the receptor proteins. METHODS DATA MINING: The potential protein target for Helminthiasis is searched in the literature databases like, (PMC) Pubmed Central and Pubmed. SEQUENCE RETRIEVAL SYSTEM: The protein sequence for H17g protein, tegumental antigen and Activated oncosphere TSO45-2A protein is retrieved from the NCBI Biological database in FASTA format. SEQUENCE SIMILARITY: The protein sequence was searched against the PDB (protein data bank) using BLASTp (Basic local alignment search tool) program for its related Templates.. SEQUENCE ANALYSIS AND COMPARISON: The relative homology to the selected study protein template was done based on the E-value cut off and the sequence similarity percentage. STRUCTURAL ANALYSIS: The primary sequence analysis was performed using PROTPARM tool to find out the H17g protein, tegumental antigen and activated oncosphere TSO45-2A protein. TERTIARY STRUCTURE PREDICTION: The tertiary structure of the H17g protein, tegumental antigen was predicted using SWISS-MODEL (An automated advanced protein modeling server) and the folds were recognized. TERTIARY STRUCTURE PREDICTION: The tertiary structure of the Activated oncosphere TSO45-2A protein was predicted using PHYRE (An automated advanced protein modeling server) and the folds were recognized. VOLUME 2 NUMBER 2 JUN

3 TERTIARY STRUCTURE VALIDATION: The tertiary structure of the H17g protein, tegumental antigen and Activated oncosphere proteins was analyzed using RAMPAGE server in order to predict stability of the protein structure. DRUG DESIGNING: Suitable ligands were selected using Pubchem databases and modified using Molinspiration server. The structural and chemical property ligand was analyzed using Toxtree server. PATCH DOCK: The selected de novo Ligands and Existing ligands are docked with H17g protein, tegumental antigen and Activated oncosphere TSO45-2A protein using advanced molecular docking server. RESULTS AND DISCUSSION Figure: 1TERTIARY STRUCTURE PREDICTION MOLEGRO MOLECULAR VIEWER STRUCTURE MODEL: H17g protein, tegumental antigen The above picture represents the red indicates the Helix regions, blue indicates the sheets and white indicates the coil regions of the H17g protein, tegumental antigen structure. Figure: 2 LIGAND SELECTION: Albendozole RASMOL- BALL and STICK model The above picture shows the three dimensional view of Albendazole (N-(6-propylsulfanyl-1H-benzimidazol-2-yl) carbamate) ligand and yellow color indicates the sulphur group, red color indicates the oxygen and blue color indicates the nitrogen. 92 VOLUME 2 NUMBER 2 JUN 2012

4 Figure: 3 Ligand selection: Benzoate (RASMOL- STICK MODEL) The above picture shows the three dimensional view of Benzoate ligand and, red color indicates the oxygen. Figure: 4 Ligand selection: Methyldithiocarbamate (STICK AND DOTTED MODEL) The above picture shows the three dimensional view of Methyldithiocarbamate ligand and yellow color indicates the sulphur group, blue color indicates the nitrogen and white colour indicates the hydrogen. MOLINSPIRATION Figure: 5 Albendazole with Benzoate = Denovo Ligand1 CCCSC1=CC2=C(C=C1) N=C (N2) NC (=O) OCC1=CC=C(C=C1) C (=O) [O-] The de novo ligand shows the drug properties values (v ) VOLUME 2 NUMBER 2 JUN

5 Figure: 6 Albendazole with Benzoate = Denovo Ligand1 CCCSC1=CC2=C(C=C1) N=C (N2) NC (=O) OCC1=CC=C(C=C1) C (=O) [O-] The de novo ligand shows the drug likeness score (v ) Figure: 7Albendazole with Methyldithiocarbamate= Denovo Ligand2 CCCSC1=CC2=C(C=C1)N=C(N2)NC(=O)OCCNC(=S)[S-].[Na+] The de novo ligand shows the drug properties values (v ) Figure: 8 Albendazole with Methyldithiocarbamate= Denovo Ligand2 CCCSC1=CC2=C(C=C1)N=C(N2)NC(=O)OCCNC(=S)[S-].[Na+] The de novo ligand shows the drug properties values (v ) 94 VOLUME 2 NUMBER 2 JUN 2012

6 Figure: 9MOLECULAR DOCKING: PATCH DOCK RESULTS Molsoft: Protein trace model, Ligand stick model Hydrophobic yellow1 ala, val, phe, pro, met, ile, leu polar pink ser, thr, tyr, his, cys, cyss, asn, gln, trp, gly Charged (+) blue lys, arg Charged (-) red asp, glu Figure: 10 Denovo Ligand and receptor protein (Activated oncosphere TSO45-2A) Figure: 11 Activated oncosphere TSO45-2A ligand complex with labels Denovo Ligand and receptor protein (H17g protein, tegumental antigen) VOLUME 2 NUMBER 2 JUN

7 Hydrophobic yellow1 ala,val,phe,pro,met,ile,leu polar pink ser,thr,tyr,his,cys,cyss,asn,gln,trp,gly Charged (+) blue lys,arg Charged (-) red asp,glu DISCOVERY STUDIO SOFTWARE: SURFACE MODEL LIGAND RECEPTOR BINDING INTERACTION Figure: 12 Activated oncosphere TSO45-2A ligand complex with labels Table: 1DRUG INTERACTION STUDIES: RECEPTOR LIGAND INTERACTION Endoparasite Drugs Denovo drugs Taenia solium Albendazole Albendazole Albendazole Targets + benzoate + methythiodiocarbomate Tegumental protein Oncosphere protein The table indicates the Patch dock results: energy binding affinities to the receptor and ligands Conclusion The increase in drug resistance among the pathogenic microbes has increased the search for novel drug targets. But very few of them have been automated and this has been a bottleneck in the in silico approach for finding drug targets.these potential protein targets, namely, H17g protein, tegumental antigen and Activated oncosphere TSO45-2A protein were selected for docking analysis with two inhibitor compounds used as ligands, namely, Benzoate and Methythiodiocarbomate. These compounds when combined with Albendazole proved to be a very effective agent in the destruction of parasitic worms. They are used therapeutically in the treatment of HELMINTHIASIS in man and animal. The above method has been proved with the help of insilico approaches.the designed ligands Albendazole with Benzoate and Albendazole with Methythiodiocarbomate and receptors, namely, H17g protein, tegumental antigen and activated oncosphere TSO45-2A are docked using automated docking server. From the results obtained, it is deduced that combined ligands (Albendazole with Benzoate and Albendazole with Methythiodiocarbomate) are better binding drug targets than just the albendazole ligand.structure-based drug designing has been successful approach in designing new/noval drugs. In-silico approaches have gained immense popularity and have become an integral part of the research that is directed towards drug design and discovery. Reference 1. RCA. THOMPSON, WJ. PENHALE, TR. WHITE, DA. PASS. BCG-induced inhibition and destruction of Taenia taeniaeformis in mice. 2007; DOI: /j tb Curtis M. Lively & Mark F. Dybdahl. Parasite adaptation to locally common host genotypes. Department of 96 VOLUME 2 NUMBER 2 JUN 2012

8 Biology, Indiana University, Bloomington, Indiana , USA. 3. J. MORALES et al., Further evaluation of the synthetic peptide vaccine S3Pvac against Taenia solium cysticercosis in pigs in an endemic town of Mexico E. SCIUTTO1, Parasitology. 2007; 134: doi: /s Ana Flisser, Ana-Elena Viniegra, Laura Aguilar-Vega, Adriana Garza-R, Pablo M and Guillermina A. Portrait of Human Tapeworms. Journal of Parasitology. 2004; 90(4): / 6. Garcia HH, Pretell EJ, Gilman RH, Martinez SM, Moulton LH, Del Brutto OH, Herrera G, Evans CA, Gonzalez AE, Cysticercosis Working Group in Peru. "A trial of antiparasitic treatment to reduce the rate of seizures due to cerebral cysticercosis". N Engl J Med. 2004; 350(3): DOI: /NEJMoa PMID Matthaiou DK, Panos G, Adamidi ES, Falagas ME. Carabin, Hélène. ed. "Albendazole versus Praziquantel in the Treatment of Neurocysticercosis: A Meta-analysis of Comparative Trials". PLoS Negl Trop Dis. 2008; 2 (3): e194. DOI: /journal.pntd PMC PMID Flisser A. "Neurocysticercosis in Mexico". Parasitology Today. 1988; 4(5): DOI: / (88) PMID Dworkin, Mark S. Outbreak Investigations Around the World: Case Studies in Infectious Disease. Jones and Bartlett Publishers. 2010; ISBN Retrieved August 9, Schantz, Peter M. et al.; Moore, Anne C.; Muñoz, José L.; Hartman, Barry J.; Schaefer, John A.; Aron, Alan M.; Persaud, Deborah; Sarti, Elsa et al. "Neurocysticercosis in an Orthodox Jewish Community in New York City". New England Journal of Medicine. 1992; 327 (10): DOI: /NEJM Retrieved August 9, VOLUME 2 NUMBER 2 JUN