Volume 39, Issue 6 e12701
ORIGINAL ARTICLE

Effects of lactic acid stress with lactic acid adaptation on the survival and expression of virulence-related genes in Escherichia coli O157:H7

Lanlin Yu

Lanlin Yu

College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China

Jiangsu Key Laboratory of Animal Origin Food Production and Safety Guarantee, Nanjing Agricultural University, Nanjing, China

Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Nanjing Agricultural University, Nanjing, China

Search for more papers by this author
Saisai Ji

Saisai Ji

School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, China

Search for more papers by this author
Jinlong Yu

Jinlong Yu

School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, China

Search for more papers by this author
Wenjing Fu

Wenjing Fu

School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, China

Search for more papers by this author
Lin Zhang

Lin Zhang

College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China

Jiangsu Key Laboratory of Animal Origin Food Production and Safety Guarantee, Nanjing Agricultural University, Nanjing, China

Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Nanjing Agricultural University, Nanjing, China

Search for more papers by this author
Jiaolong Li

Jiaolong Li

College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China

Jiangsu Key Laboratory of Animal Origin Food Production and Safety Guarantee, Nanjing Agricultural University, Nanjing, China

Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Nanjing Agricultural University, Nanjing, China

Search for more papers by this author
Feng Gao

Feng Gao

College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China

Jiangsu Key Laboratory of Animal Origin Food Production and Safety Guarantee, Nanjing Agricultural University, Nanjing, China

Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Nanjing Agricultural University, Nanjing, China

Search for more papers by this author
Yun Jiang

Corresponding Author

Yun Jiang

School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, China

Correspondence

Yun Jiang, School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China.

Email: [email protected]

Search for more papers by this author
First published: 27 August 2019
Citations: 5

Funding information: National Key Research and Development Program of China, Grant/Award Number: 2016YFD0500501; National Natural Science Foundation of China, Grant/Award Numbers: 31371861, 31671915

Abstract

This study was aimed to investigate the effects of lactic acid stress with acid adaptation on the survival and expression of virulence-related genes in Escherichia coli O157:H7 (strains CICC21530, 89, 95, 112, 109, and J42). E. coli were subjected to acid adaption (pH 5.0) for 1–4 hr and then exposed to acid stress (pH 3.5) for 30–120 min. Results showed that exposure to pH 3.5 decreased the survival of E. coli strains, in which strains 109, 112, and J42 had stronger acid resistance. The expression of virulence-related genes of most strains decreased after exposure to pH 3.5 compared with nonstressed cells. In addition, acid adaptation increased the acid resistance of most strains, except for CICC21530 and J42. And the virulence expression of most acid-adapted cells decreased or showed no significant changes compared with nonadapted cells. There were no obvious relationships between the survival and expression of virulence-related genes in E. coli O157:H7 strains. However, variable acid resistance of acid-adapted strains was existed, and some acid adaptation increased the strain survival and expression of virulence-related genes, which may still threaten food safety.

Practical Applications

This study evaluated the effects of lactic acid stress with acid adaptation on the survival and expression of virulence-related genes in Escherichia coli O157:H7. Acid adaptation could enhance the survival and virulence expression of some strains, which will threaten the safety of acidic food during processing and storage. Furthermore, variable acid resistance of acid-adapted strains should be noticed in surveillance and control of E. coli O157:H7 in environment and food, which is beneficial for its scientific and effective risk assessment and control.

The full text of this article hosted at iucr.org is unavailable due to technical difficulties.