| Summary: | The genus <i>Geobacillus</i> comprises thermophilic gram-positive bacteria which are widely distributed, and their ability to withstand high temperatures makes them suitable for various applications in biotechnology and industrial production. <i>Geobacillus stearothermophilus</i> H6 is an extremely thermophilic <i>Geobacillus</i> strain isolated from hyperthermophilic compost at 80 °C. Through whole-genome sequencing and genome annotation analysis of the strain, the gene functions of <i>G. stearothermophilus</i> H6 were predicted and the thermophilic enzyme in the strain was mined. The <i>G. stearothermophilus</i> H6 draft genome consisted of 3,054,993 bp, with a genome GC content of 51.66%, and it was predicted to contain 3750 coding genes. The analysis showed that strain H6 contained a variety of enzyme-coding genes, including protease, glycoside hydrolase, xylanase, amylase and lipase genes. A skimmed milk plate experiment showed that <i>G. stearothermophilus</i> H6 could produce extracellular protease that functioned at 60 °C, and the genome predictions included 18 secreted proteases with signal peptides. By analyzing the sequence of the strain genome, a protease gene <i>gs-sp1</i> was successfully screened. The gene sequence was analyzed and heterologously expressed, and the protease was successfully expressed in <i>Escherichia coli</i>. These results could provide a theoretical basis for the development and application of industrial strains.
|
|---|