Abstract
Bacillus subtilis is the best studied Gram-positive bacterium, primarily as a model of cell differentiation and industrial exploitation. To date, little is known about the virulence of B. subtilis. In this study, we examined the virulence potential of a B. subtilis strain (G7) isolated from the Iheya North hydrothermal field of Okinawa Trough. G7 is aerobic, motile, endospore-forming, and requires NaCl for growth. The genome of G7 is composed of one circular chromosome of 4,216,133 base pairs with an average GC content of 43.72%. G7 contains 4,416 coding genes, 27.5% of which could not be annotated, and the remaining 72.5% were annotated with known or predicted functions in 25 different COG categories. Ten sets of 23S, 5S, and 16S ribosomal RNA operons, 86 tRNA and 14 sRNA genes, 50 tandem repeats, 41 mini-satellites, one microsatellite, and 42 transposons were identified in G7. Comparing to the genome of the B. subtilis wild type strain NCIB 3610T, G7 genome contains many genomic translocations, inversions, and insertions, and twice the amount of genomic Islands (GIs), with 42.5% of GI genes encoding hypothetical proteins. G7 possesses abundant putative virulence genes associated with adhesion, invasion, dissemination, anti-phagocytosis, and intracellular survival. Experimental studies showed that G7 was able to cause mortality in fish and mice following intramuscular/intraperitoneal injection, resist the killing effect of serum complement, and replicate in mouse macrophages and fish peripheral blood leukocytes. Taken together, our study indicates that G7 is a B. subtilis isolate with unique genetic features and can be lethal to vertebrate animals once being introduced into the animals by artificial means. These results provide the first insight into the potential harmfulness of deep-sea B. subtilis.
Highlights
Bacillus species are aerobic, rod-shaped bacteria that stain Gram-positive or Gram-negative (Cote et al, 2015)
Strain G7 was isolated from the deep-sea water collected from Iheya North hydrothermal field
In the genome tree based on the 1113 orthologous genes (Figure 2B), the B. subtilis species formed a group, which was separated from that formed by Bacillus cereus and Bacillus anthracis, and strain G7 was a member of B. subtilis subsp. subtilis
Summary
Rod-shaped bacteria that stain Gram-positive or Gram-negative (Cote et al, 2015) They form spores that are resistant to cold, heat, and common disinfectants, enabling the bacteria to survive in various environments (Brown, 2000; Cote et al, 2015). A Virulent Bacillus From Deep-Sea in animals and humans (Spencer, 2003). A report showed that, of the many isolates obtained from four different deep sea sediments, the vast majority (90%) were spore-forming bacteria related to Bacillus (Sass et al, 2008). Phylogenetic, genomic, and potential virulence of strain G7, and provided the first insight into the detrimental effect of Bacillus species from deep-sea hydrothermal vent
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
