Lu_2026_Food.Microbiol_139_105127

In this study, we overexpressed luxS, a key gene in the LuxS/AI-2 quorum sensing (QS), to construct Lactiplantibacillus plantarum HRB1 pMG36e-luxS, and evaluated its fermentation characteristics both in vitro and dry-sausage model. In vitro, overexpression of the luxS gene significantly enhanced strain growth, AI-2 production, protease activity, and lipase activity. In the dry sausage model, inoculation with the recombinant strain accelerated acidification and maintained L. plantarum as the dominant species during the fermentation process. Moreover, dry sausages inoculated with L. plantarum HRB1 pMG36e-luxS exhibited a higher total free amino acids (27.37 mg/g), total esters (1434.55 microg/kg), and key volatile compounds, notably acetoin and 1-hexanol, thereby improving sensory attributes such as fermented odor and fatty odor. Overall, luxS gene overexpression enhances the fermentation capability (acidification, protease activity, and lipase activity) and flavor formation capability of L. plantarum HRB1 by strengthening LuxS/AI-2-associated regulatory, thereby improving dry sausage quality and establishing a theoretical basis for the foundation of engineered starter culture with a functional LuxS/AI-2 QS.