Bacillus Subtilis

Definition – What is the meaning of Bacillus Subtilis?

Bacillus licheniformis is a spore-forming soil organism that contributes to nutrient cycling and has antifungal activity. There is current research on B. licheniformis (strain SB3086) and its effects as a microbial fungicide. Novozymes Biofungicide Green Releaf contains B. licheniformis strain SB3086 as an active main ingredient. This fungicide can be used on lawns, conifers, tree seedlings, ornamental turf and ornamental plants in outdoor, greenhouse, and nursery sites. There are concerns regarding the safety of this fungicide. Reports about Bacillus licheniformis having detrimental effects on insect, avian, plant, and estuarine marine species are fortunately almost non-existent.

Bacillus Subtilis explained by Bud Bionics

Habitat

This species is commonly found in the upper layers of the soil, and evidence exists that B. subtilis is a normal gut commensal in humans. A 2009 study compared the density of spores found in soil (about 106 spores per gram) to that found in human feces (about 104 spores per gram). The number of spores found in the human gut was too high to be attributed solely to consumption through food contamination. B. subtilis has been linked to grow in higher elevations and act as an identifier for both eco-adaptability and honey bee health.

Reproduction

Bacillus subtilis is a Gram positive, rod shaped bacteria, commonly found in soil. It was originally named “Vibrio subtilis” when it was discovered in 1835 by Christian Gottfried Ehrenberg. It was renamed “Bacillus subtilis” in 1872 by Ferdinand Cohn. This bacterium is also known by the names hay bacillus, grass bacillus, or Bacillus globigii. Bacillus subtilis is an endospore forming bacteria, and the endospore that it forms allows it to withstand extreme temperatures as well as dry environments. Bacillus subtilis is considered and obligate aerobe, but can also function anaerobicly when in the presence of nitrates or glucose. Bacillus subtilis is not considered pathogenic or toxic and is not a disease-causing agent. Bacillus subtilis has a flagellum which makes motility faster.

Since this bacterium is resistant to extreme temperatures, it can with stand high cooking temperatures. This is not to cause alarm, as it does not cause sickness if ingested. This bacterium can cause a stringy consistency in spoiled bread dough, if dough is exposed.

Bacillus subtilis is readily present everywhere; the air, soil and in plant compost. It is predicted that it spends most of it time inactive and in spore form. When the bacterium is active though, it produces many enzymes. One enzyme contributes to the plant degradation process. Bacillus subtilis can also be found in the human body, mostly on the skin or in the intestinal tract. However, it is very rare for this bacterium to colonize on the human body.

Along with enzymes, Bacillus subtilis also produces a toxin called subtilisin. Subtilisin can cause allergic reactions if there is repeated exposure in high concentrations. This only poses a risk to fermentation plants that use high quantities of subtilisin. Exposure restrictions have been imposed by OSHA for the factory setting and can be found on their website (Occupational Safety & Health Administration). Subtilisin is also used in laundry detergent. It has been known to cause allergic reactions after using such detergent, however only in large quantities.

There are several uses for Bacillus subtilis and the enzymes it produces. It can be used to create proteases and amylase enzymes. At one-point Bacillus subtilis was widely used as a broad-spectrum antibiotic. This was lost after the ability to produce cheaper, large-scale antibiotics. It is still used in Western Europe and the Middle East in alternative medicine. Bacillus subtilis can convert dangerous explosives into just compounds of nitrogen, carbon dioxide and water (Wikipedia). The proton binding properties of the surface of this bacterium can also play a role in the degradation of radioactive waste (Wikipedia). Bacillus subtilis has also been used as a soil inoculant, and was at one time used in biological warfare tests run during the Cold War. Other commercial applications of Bacillus subtilis include cleaning agents in detergents, in de-haring and batting in the leather industry, in the production of special Japanese and Korean food, starch modification, the de-sizing of textiles, and other specialized chemicals. Bacillus subtilis also produces some fungicidal compounds, which are being investigated as control agents of fungal pathogens. It is currently being used as a fungicide for plant and ornamental seeds as well as various agricultural seeds.

Besides its many uses and applications, Bacillus subtilis has become the model agent in laboratory research because of its easy genetic manipulation.

« Back to Glossary Index