Quorum sensing is the regulation of gene expression in response to fluctuations in cell-population density. Quorum sensing bacteria produce and release chemical signal molecules called auto-inducers that increase in concentration as a function of cell density. The detection of a minimal threshold stimulatory concentration of an auto-inducer leads to an alteration in gene expression. Gram-positive and Gram-negative bacteria use quorum sensing communication circuits to regulate a diverse array of physiological activities. These processes include symbiosis, virulence, competence, conjugation, antibiotic production, motility, sporulation, and biofilm formation .It is well supported by the finding that the pathogenic and non -pathogenic organisms the proteins are stable in these organisms, which could be inferred by the instability index. Moreover, the conversation was found since it is stable. This work represents a series of interrelated modules designed to introduce you to modern biological techniques in the area of bioinformatics.