کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5740126 | 1616236 | 2017 | 8 صفحه PDF | دانلود رایگان |
- The role of each HK of L. monocytogenes was assessed under various stresses.
- LiaS plays a universal role in stress response of L. monocytogenes EGD-e.
- Complete AgrAC and VirRS is needed at osmotic and ethanol stress, respectively.
- A novel complementation approach for L. monocytogenes is introduced.
To study the role of each two-component system (TCS) histidine kinase (HK) in stress tolerance of Listeria monocytogenes EGD-e, we monitored the growth of individual HK deletion mutant strains under heat (42.5 °C), acid (pH 5.6), alkali (pH 9.4), osmotic (6% NaCl), ethanol (3.5 vol%), and oxidative (5 mM H2O2) stresses. The growth of ÎliaS (Îlmo1021) strain was impaired under each stress, with the most notable decrease under heat and osmotic stresses. The ÎvirS (Îlmo1741) strain showed nearly completely restricted growth at high temperature and impaired growth in ethanol. The growth of ÎagrC (Îlmo0050) strain was impaired under osmotic stress and slightly under oxidative stress. We successfully complemented the HK mutations using a novel allelic exchange based approach. This approach avoided the copy-number problems associated with in trans complementation from a plasmid. The mutant phenotypes were restored to the wild-type level in the complemented strains. This study reveals novel knowledge on the HKs needed for growth of L. monocytogenes EGD-e under abovementioned stress conditions, with LiaS playing multiple roles in stress tolerance of L. monocytogenes EGD-e.
Journal: Food Microbiology - Volume 65, August 2017, Pages 36-43