Isolation and thermo-acclimation of thermophilic bacteria in hyperthermophilic fermentation system

• Published in: Bioprocess and biosystems engineering Vol. 45; no. 1; pp. 75 - 85
• Main Authors: Wang, Zhiquan, Wu, Suqing, Fan, Chunzhen, Zheng, Xiangyong, Wu, Deyi, Wang, Xinze, Kong, Hainan
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.01.2022; Springer Nature B.V
• Subjects: Acclimation; Acclimatization; amino acid composition; Amino acids; Archaea - physiology; Bacillus thermoamylovorans; Bacteria; Bacterial Physiological Phenomena; bioprocessing; Biotechnology; Chemistry; Chemistry and Materials Science; Composting; Environmental Engineering/Biotechnology; Fermentation; Food Science; Heating rate; High temperature; Hot Temperature; Hydrophobicity; Industrial and Production Engineering; Industrial Chemistry/Chemical Engineering; Membrane permeability; Microorganisms; Operating temperature; Research Paper; Sludge; temperature; Thermaerobacter; Thermal stability; Thermophilic bacteria; Thermophilic microorganisms; Thermostability; Hyper-thermophiles; Maximum temperature; Hubs amino acids; Thermo-acclimation
• ISSN: 1615-7591; 1615-7605; 1615-7605
• DOI: 10.1007/s00449-021-02640-5

Hyperthermophilic microorganisms play a key role in the hyper-thermophilic composting (HTC) technique. However, little information is available about the hyperthermophilic microorganisms prevalent in HTC systems, except for the Calditerricola satsumensis , Calditerricola yamamurae , and Thermaerobacter . To obtain effective hyper-thermophilic microorganisms, a continuous thermo-acclimation of the suitable thermophilic microorganisms was demonstrated in this study. Bacillus thermoamylovorans with high-temperature endurance (70 °C) were newly isolated from sludge composting, and an adequate slow heating rate (2 °C per cycle) was applied to further improve its thermostability. Finally, a strain with a maximum growth temperature of 80 °C was obtained. Moreover, structural and hydrophobic changes in cell proteins, the special amino acid content ratio, and the membrane permeability of the thermophilic bacterium after thermo-acclimation were evaluated for improved thermostability. In addition, the acclimated hyperthermophilic bacterium was further inoculated into the HTC system, and an excellent performance with a maximum operating temperature of 82 °C was observed. Graphic abstract