Abstract
Spoilage of juice and beverages by a thermo-acidophilic bacterium, Alicyclobacillus acidoterrestris, has been considered to be a major and widespread concern for juice industry. Acid-resistant property of A. acidoterrestris supports its survival and multiplication in acidic juice and challenges the development of corresponding control measures. In this study, intracellular amino acid differences caused by acid stress (pH 3.0, 1 h) were determined by targeted metabolomics. The effect of exogenous amino acids on acid resistance of A. acidoterrestris and the related mechanisms were also investigated. The results showed that acid stress affected the amino acid metabolism of A. acidoterrestris, and the selected glutamate, arginine, and lysine contributed to its survival under acid stress. Exogenous glutamate, arginine, and lysine significantly increased the intracellular pH and ATP level, alleviated cell membrane damage, reduced surface roughness, and suppressed deformation caused by acid stress. Additionally, the up-regulated gadA and speA genes and the enhanced enzymatic activity confirmed that glutamate and arginine decarboxylase systems played a crucial role in maintaining pH homeostasis of A. acidoterrestris under acid stress. Our research reveals an important factor contributing to acid resistance of A. acidoterrestris, which provides an alternative target for effectively controlling this contaminant in fruit juices.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.