Insights into Brevibacillus borstelensis AK1 through Whole Genome Sequencing: A Thermophilic Bacterium Isolated from a Hot Spring in Saudi Arabia

Abstract

Brevibacillus borstelensis AK1 is a thermophile which grows between the temperatures of 45°C and 70°C. The present study is an extended genome report of B. borstelensis AK1 along with the morphological characterization. The strain is isolated from a hot spring in Saudi Arabia (southeast of the city Gazan). It is observed that the strain AK1 is rod-shaped, motile, and strictly aerobic bacterium. The whole genome sequence resulted in 29 contigs with a total length of 5,155,092 bp. In total, 3,946 protein-coding genes and 139 RNA genes were identified. Comparison with the previously submitted strains of B. borstelensis strains illustrates that strain AK1 has a small genome size but high GC content. The strain possesses putative genes for degradation of a wide range of substrates including polyethylene (plastic) and long-chain hydrocarbons. These genomic features may be useful for future environmental/biotechnological applications.

Figure 1

Scanning electron micrographs of Brevibacillus borstelensis strain AK1 at 10.0 kx (a), 20.0 kx (b), and 100.0 kx (c).

Figure 2

Molecular Phylogenetic analysis by Maximum Likelihood method highlighting the position of Brevibacillus borstelensis AK1 relative to other similar bacteria. Bootstrap values based on 1000 replicates show the robustness of the branching. Scale bar represents 0.1 substitutions per nucleotide position. The tree is drawn to scale, with branch lengths measured in the number of substitutions per site.

Figure 3

Graphical circular map drawn using ClicO FS [22]. The outer circle represents contigs information, whereas the next two inner circles present ORFs oriented in the forward (blue) and reverse (purple) direction. The 4th circle marks tRNA gene operon (orange) while 5th circle represents rRNA genes (red). The sixth circle reflects GC content plot (%age). The innermost circle shows GC skew; red indicates negative values, whereas black indicates positive values. The scale bar is in Mb.