Objective: The use of high-temperature Daqu is an important characteristic in Chinese Maotai-flavor liquor making. Thermostable bacteria are predominant in high-temperature Daqu. They play important roles in Maotai-flavor liquor making. Learning the mechanism of thermotolerant performance of bacteria would provide insight into characteristics of this liquor making.
Methods: We determined the thermotolerance of Bacillus licheniformis CGMCC 3963, and analyzed cell morphology, genomics and transcriptomics.
Results: B. licheniformis CGMCC 3963 could survive at 55 degrees C and produce many capsules. Genes of class I heat-shock proteins and polyglutamate biosynthesis were both up-regulated.
Conclusion: Much heat-shock proteins and capsule polyglutamate maintained the survival of cell with heat stress.