Investigation of bacterial infection strategies through bacteria-human protein-protein interactions by bioinformatics approaches

Infectious diseases, which have been a serious threat for human life in ancient times, is still leading the causes of death and disability worldwide. Pathogens (viruses, bacteria, protozoa, fungi, etc.) express a wide range of molecules that bind to host cell targets to manipulate human mechanisms for their own advantage, and result in infection in the host organism. Well characterization of these interspecies (pathogen-human) interactions is required for a complete understanding of pathogenesis. The key point of fighting with infectious diseases is the identification and characterization of the strategies used by these pathogens to interact with the host, as these strategies are usually unique to specific pathogens or conserved across several different species. Within the framework of this project, bacterial infection mechanisms are investigated through bacteria-human protein-protein interactions. The targeted human proteins with specific properties different from the non-targeted ones are analyzed to enlighten several infection mechanisms. Gene Ontology enrichments of targeted human proteins are investigated; that is, all three GO terms are examined to identify the terms having significant association with each human protein set studied. In addition to GO terms, Kegg pathways, transcription factor targets and pathway commons of the targeted human proteins are identified. A thorough bioinformatic based analysis of bacteria-human protein interaction network is still missing in the literature. This study is the first attempt to comprehensively investigate bacterial infection strategies through bacteria-human protein-protein interactions. Common and specific infection strategies of different types of bacteria are identified, contributing to the novelty of the present research work.