Chemotaxis is the most simple model system for investigating the behaviour of an organism but still exploits an elegant as well as complex mechanism. This type of behaviour to various stimuli from environments is a response at the posttranslational level, and there are no informations whether specific operons are regulated by chemotactic signals. Thus, to verify and identify this type of stimulons, lacZ operon fusions are constructed by using of Tn10-lacZ derivative which can make insertions into quasi-random sites of bacterial chromosome. In this work, I isolated 3 significant candidate fusions whose expressions are increased by chemotactic counterolockwise signals. $\Phi$c1 in which $\varphi$ is a symbol for lacZ fusion, is located around 18 min on the chromosome, and $\varphi$ c4 located around 10 min., and $\varphi$ csions of this type can implied the existence of stimulons regulated by chemotactic signal but those should be further confirmed.