Nazanin Gholampour-Faroji - Department of Biology, Khorasan Razavi Science and Research Branch, Islamic Azad University, Neyshabur, Iran
Aliakbar Haddad-Mashadirizeh - Cell and Molecular Biotechnology Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran
Samaneh Dolatabadi - Department of Biology, Neyshabur Branch, Islamic Azad University, Neyshabur, Iran

Reactive oxygen species are involved in various aspects of tumor development. Bearing inmind, provide approaches for elimination these components can be a promising vision forcancer prevention. Reports suggest reducing the toxic effects of reactive oxygen speciesthrough administration of probiotics. So, a thorough understanding of probiotic ingredients,products, proteins and their affecting molecular mechanisms would be influence in thedevelopment and selection of efficiently type of the anti-cancer probiotic strains, whichconsidered in this study based on in-silico investigation on involved molecular mechanisms.In this regard, a comprehensive profile of probiotics and corresponding antioxidativeenzymes as well as related molecular mechanisms were collected. Nucleotide and proteinsequences and structure of selected genes as well as 3D structure of reactive oxygenspecies were retrieved from GeneBank, UniProt, ExPASY, PDB and Colby, Pubchem, asrespectively. Molecular and reaction analysis of these sequences were performed based onapplication of a series of online and offline programs including InterProScan, Motif scan,Conserved Domain, ProtParam, PatchDock, Swissmodel, Blast, MEGA6 and Pymol. Theresults of this investigation led to the introduction catalase (katA), superoxide dismutase(sodA), thioredoxin reductase (trxB) and glutathione reductase (gshR1) as the bestantioxidative enzymes with suitable interaction to reactive oxygen species in probioticsstrains. Homology search of these enzymes lead to discovery a different species of bacteriawith likely antioxidative capacity. Moreover, specific domains with various lengths weredisclosed in protein sequences of these enzymes which are involved in decomposition ofH2O2, cleaning up of superoxide radical and also in immunomodulatory effects. Takentogether, the results of this research while lead to disclose new bacteria with antioxidativecapacity reveal molecular mechanisms of antioxidative effects of prevalent probiotics andalso a set of domains used for designing competent genetics constructs for increase potentialof antioxidative ability which ought to be more investigated.

Reactive, Oxygen, Species, Cancer, Probiotics