*Corresponding author:NageswaraRao R. Neelapu Department of Bioinformatics, School of Life Sciences, GITAM Institute of Science, GITAM University, Rushikonda campus, Visakhapatnam – 530045 (AP), India. ISSN:0976-3031 ResearchArticle SCREENING AND IDENTIFICATION OF DRUG TARGETS AND VACCINE CANDIDATES FOR HELICOBACTER PYLORI STRAIN Hp26695 Amita Martin Corolina Pasupuleti, Deepthi Nammi and Nageswara Rao Reddy Neelapu* Department of Bioinformatics, School of Life Sciences, GITAM Institute of Science, GITAM University, Rushikonda campus, Visakhapatnam – 530045 (AP), India. DOI: http://dx.doi.org/10.24327/ijrsr.2017.0804.0140 ARTICLE INFO ABSTRACT Helicobacter pylori, a class 1 carcinogen colonizes stomach causing gastric carcinoma. Rising antibiotic resistance and reinfections are drawbacks of antibiotic therapies. Alternating drugs and vaccination may be the promising approach to prevent and treat reoccurring infections. Therefore, there is a need for discovery of drug targets, drugs and vaccine candidates for the treatment of H. pylori. An objective of this current study is to identify potential drug targets and suitable vaccine candidates for H. pylori strain Hp26695 by insilico genome and proteome analysis. Drug targets were identified initially by comparing the genomes between H. pylori and Homosapien sapiens using RAST. RAST identified a total of 569 unique genes. These unique genes later were subjected to non-homology and gene property analysis to identify the potential drug targets. BLASTpfollowed by gene property analysis of 569 unique genes identified seven potential drug targets. Vaccine candidates were identified initially by screening protein sequences for pathogenic factors. These pathogenic factors were screened to identify non-homologous molecules and secondary structure patterns (helices). The proteins ≤ 3 helices are subjected to screening of antigenic nature followed by allergenicity. The proteins qualifying the above criteria were screened for antigens, B- cells and T-cell epitopes. Proteins showing positive predictions for antigenic, B-cell, T-cell activities are thus shortlisted as vaccine candidates for vaccine designing. Analysis identified 16 immunogenic proteins contributing to immune-response. These methods have enabled rapid identification of potential drug targets and vaccine candidates for strain Hp26695 with possible therapeutic implications for gastric cancer. cancer. INTRODUCTION Gastric cancer is caused by infection of class 1 carcinogen Helicobacter pylori (Zhang, 1994). Treatment for H. pylori infection includes drugs to relieve from pain and acidity, but not for gastritis, peptic ulcers, and gastric cancer. Carcinogenic activity of H. pylori suggests the need for discovery of new drug targets and drugs for prevention of H. pylori. Laboratory techniques and bioinformatics approaches are used to identify drug targets which can influence growth, colonization and virulence of H. pylori(Neelapuet al., 2014). Availability of the complete H. pylori genome sequence of pathogens provides us the platform and opportunity to mine the genome and harness the potential drug targets. Comparative genomic analysis between host and pathogen would provide us with a tremendous amount of information that can be useful in drug target identification (Neelapuet al., 2013).Comparative genomics analysis of host with pathogens revealed potential drug targets in Staphylococcus aureus (Uddinet al., 2014), H. pylori (Neelapu and Pavani, 2013; Neelapuet al., 2015;Nammiet al., 2016)Listeria monocytogenes(Hossainet al., 2013), Leishmaniainfantum(Sutharet al., 2009), L. major (Florezet al., 2010), Mycobacterium leprae(Wiwanitkit, 2014), Pseudomonas aeruginosa(Sakharkaret al., 2004), Schistosomamansomi(Caffreyet al., 2009).Metabolic pathway analysis (Sarkaret al., 2012), reverse docking (Caiet al., 2006) and screening for essential genes (Duttaet al., 2006) are used to identify drug targets in H. pylori. However, there are no specific reports to date, on comparing genomes of H. pylori strain Hp26695 with host Homosapiens to identify drug targets in H. pylori. Therefore, comparing genome of host and pathogen may provide novel drug targets for H. pylori strainHp26695. Available Online at http://www.recentscientific.com International Journal of Recent Scientific Research International Journal of Recent Scientific Research Vol. 8, Issue, 4, pp. 16384-16395, April, 2017 Copyright © Amita Martin Corolinaet al, 2017, this is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited. Article History: Received 15 th January, 2017 Received in revised form 25 th February, 2017 Accepted 28 th March, 2017 Published online 28 th April, 2017 DOI: 10.24327/IJRSR CODEN: IJRSFP (USA)