Abstract:Quorum sensing gene luxI/luxR of Aeromonas sobria was used for this study, and the effect of different environmental conditions on the expression of this gene was investigated from the transcription level by real-time fluorescence quantitative PCR to determine the regulatory effect of environmental factors on quorum sensing system. The results showed that the expression level of luxI/luxR gene was the highest at appropriate low temperature (15 ℃) and weak base (pH = 8), while the expression level of both genes decreased under high osmotic stress. When glucose was the carbon source, the expression of luxI/luxR gene was the highest, and luxI gene was more sensitive to carbon sources than luxR gene. The expression level of luxI gene under different nitrogen sources was as follows: tryptone > ammonium chloride > beef extract > yeast extract > urea, and the expression of luxR gene was as follows: tryptone > ammonium chloride > yeast extract > beef extract > urea. Therefore, the changes of environmental conditions can be used to regulate quorum sensing system in Aeromonas sobria, so as to control its spoilage ability.