Etter Danai, Jenni Céline, Tasara Taurai, Johler Sophia
Institute for Food Safety and Hygiene, University of Zurich, 8057 Zurich, Switzerland.
Laboratory of Food Microbiology, Institute for Food, Nutrition and Health (IFNH), ETH Zurich, 8092 Zurich, Switzerland.
Microorganisms. 2021 May 8;9(5):1014. doi: 10.3390/microorganisms9051014.
Staphylococcal enterotoxin C (SEC) is a major cause of staphylococcal food poisoning in humans and plays a role in bovine mastitis. () benefits from a competitive growth advantage under stress conditions encountered in foods such as a low pH. Therefore, understanding the role of stressors such as lactic acid on SEC production is of pivotal relevance to food safety. However, stress-dependent cues and their effects on enterotoxin expression are still poorly understood. In this study, we used human and animal strains harboring different SEC variants in order to evaluate the influence of mild lactic acid stress (pH 6.0) on SEC expression both on transcriptional and translational level. Although only a modest decrease in mRNA levels was observed under lactic acid stress, protein levels showed a significant decrease in SEC levels for some strains. These findings indicate that post-transcriptional modifications can act in SEC expression under lactic acid stress.
葡萄球菌肠毒素C（SEC）是人类葡萄球菌食物中毒的主要原因，并且在牛乳腺炎中起作用。（）在诸如低pH等食品中遇到的应激条件下受益于竞争性生长优势。因此，了解诸如乳酸等应激源对SEC产生的作用与食品安全至关重要。然而，应激相关线索及其对肠毒素表达的影响仍知之甚少。在本研究中，我们使用携带不同SEC变体的人源和动物菌株，以评估轻度乳酸应激（pH 6.0）对SEC在转录和翻译水平表达的影响。尽管在乳酸应激下仅观察到mRNA水平适度下降，但某些菌株的蛋白质水平显示SEC水平显著下降。这些发现表明转录后修饰可在乳酸应激下作用于SEC表达。
