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The opportunistic pathogen Klebsiella pneumoniae is a causative agent of several hospital-acquired infections. It has become resistant to a wide range of currently available antibiotics, leading to high mortality rates among patients; this has further led to a demand for novel therapeutic intervention to treat such infections. Using a series of in silico analyses, the present study aims to explore novel drug/vaccine candidates from the hypothetical proteins of K. pneumoniae. A total of 540 proteins were found to be hypothetical in this organism. Analysis of these 540 hypothetical proteins revealed 30 pathogen-specific proteins essential for pathogen survival. A motifs/domain family analysis, similarity search against known proteins, gene ontology, and protein-protein interaction analysis of the shortlisted 30 proteins led to functional assignment for 17 proteins. They were mainly cataloged as enzymes, lipoproteins, stress-induced proteins, transporters, and other proteins (viz., two-component proteins, skeletal proteins and toxins). Among the annotated proteins, 16 proteins, located in the cytoplasm, periplasm, and inner membrane, were considered as potential drug targets, and one extracellular protein was considered as a vaccine candidate. A druggability analysis indicated that the identified 17 drug/vaccine candidates were "novel". Furthermore, a host-pathogen interaction analysis of these identified target candidates revealed a betaine/carnitine/choline transporters (BCCT) family protein showing interactions with five host proteins. Structure prediction and validation were carried out for this protein, which could aid in structure-based inhibitor design.

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Breast cancer is the leading cause for mortality among women worldwide. Dysregulation of oncogenes and tumor suppressor genes is the major reason for the cause of cancer. Understanding these genes will provide clues and insights about their regulatory mechanism and their interplay in cancer. In the present study, an attempt is made to compare the functional characteristics and interactions of oncogenes and tumor suppressor genes to understand their biological role. 431 breast cancer samples from seven publicly available microarray datasets were collected and analysed using GEO2R tool. The identified 416 differentially expressed genes were classified into five gene sets as oncogenes (OG), tumor suppressor genes (TSG), druggable genes, essential genes and other genes. The gene sets were subjected to various analysis such as enrichment analysis (viz., GO, Pathways, Diseases and Drugs), network analysis, calculation of mutation frequencies and Guanine-Cytosine (GC) content. From the results, it was observed that the OG were having high GC content as well as high interactions than TSG. Moreover, the OG are found to have frequent mutations than TSG. The enrichment analysis results suggest that the oncogenes are involved in positive regulation of cellular protein metabolic process, macromolecule biosynthetic process and majorly in cell cycle and focal adhesion pathway in cancer. It was also found that these oncogenes are involved in other diseases such as skin diseases and viral infections. Collagenase, paclitaxel and docetaxel are some of the drugs found to be enriched for oncogenes.

Dengue virus is a mosquito-borne human pathogen, causing disease that ranges from mild febrile illness to life-threatening hemorrhage fever/ shock syndrome. The altered antigenicity and virulence in the dengue virus, resulting from the accumulation and fixation of the favorable mutations in the genome, is the cause of concern nowadays. The present study focuses on the comparative study of polyproteins of viral strains within each dengue serotype to understand the trend of intra-serotype polyprotein variation and its effect on the antigenicity. Polyprotein sequences of viral strains in each serotype were investigated using multivariate statistical analysis, phylogenetic analysis and multiple sequence alignment methods. Epitope prediction was done by Bepipred-1.0 server and experimental epitope data were extracted from Immune Epitope Database with BLAST search. The study reveals that the polyproteins of viral strains of a serotype have variable amino acid composition that corresponds to the geographical regions of origin. This compositional variation has occurred due to the presence of polymorphic residues at different positions along the polyprotein sequence. The polymorphic residues have also been identified at epitope regions of structural proteins as well as NS1 of viral strains, possessing dissimilar physicochemical properties and occupy surface accessible positions. These positions on epitopes with polymorphic, dissimilar and surface accessible residues might act as putative sites for generation of antigenic variation among viral strains of a serotype of different geographical origin. Thus, these polymorphic residue positions on epitopes might be considered as putative target for development of drug or vaccine, in future.