FOOD SCIENCE ›› 2019, Vol. 40 ›› Issue (10): 50-56.doi: 10.7506/spkx1002-6630-20180619-359

• Bioengineering • Previous Articles     Next Articles

Role of phoP Regulon in Environmental Stress Tolerance in Cronobacter sakazakii

ZHOU Yaqin, LI Mengyun, XIA Xiaodong*   

  1. College of Food Science and Engineering, Northwest A&F University, Yangling 712100, China
  • Online:2019-05-25 Published:2019-05-31

Abstract: The aim of this study was to investigate the effect of the phoP regulon on environmental stress tolerance in Cronobacter sakazakii. A phoP-deleted strain of C. sakazakii was constructed by using the Red homologous recombination method, and then the growth curve and stress tolerance of the phoP-deleted strain were examined. The results showed that the phoP-defective strain showed delayed growth and weaker tolerance to external acid-base and heat stress. Meanwhile, it exhibited shortened time of death from heat treatment. phoP rendered C. sakazakii tolerant to bile salt environment, and its deletion resulted in a reduction in survival rate of 19.93% (P < 0.05), 40.73% (P < 0.01) and 45.84% (P < 0.01) in 4%, 8% and 12% bile salt solutions, respectively. The tolerance to osmotic pressure of the phoP gene-deficient strain was also significantly lower than that of the wild-type strain (P < 0.05). In conclusion, phoP enables C. sakazakii to respond to environmental stimuli.

Key words: phoP, Cronobacter sakazakii, environmental tolerance

CLC Number: