Bacillus subtilis

bacterium

Also known as: hay bacillus

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Last updated

June 23, 2026

Quick Summary

Bacillus subtilis is a rod-shaped bacterium commonly found in soil and decaying organic matter. It is a gram-positive, aerobic bacterium, meaning it thrives in the presence of oxygen.12

A key characteristic of Bacillus species, including B. subtilis, is their ability to form dormant, heat-resistant structures called endospores when environmental conditions become unfavorable. These endospores can survive for extended periods and are resistant to heat, chemicals, and radiation. When conditions improve, these spores can revert to an actively growing state.13

While B. subtilis is often a contaminant in laboratory settings and can be found on human skin, most strains are not pathogenic. However, some Bacillus species can cause issues like food spoilage or food poisoning. Medically, B. subtilis is notable for producing the antibiotic bacitracin.1

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bacillus
…hay bacillus (now known as Bacillus subtilis): one that could be killed upon exposure to heat and one that was resistant to heat. He called the heat-resistant forms “spores” (endospores) and discovered that these dormant forms could be converted to a vegetative, or actively growing, state. Today it is known…
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…hay bacillus (now known as Bacillus subtilis): one that could be killed upon exposure to heat and one that was resistant to heat. He called the heat-resistant forms “spores” (endospores) and discovered that these dormant forms could be converted to a vegetative, or actively growing, state. Today it is known…
Read More

Charles Yanofsky
coli and Bacillus subtilis. While conducting experiments focused on discerning the mechanisms of this process in 1981, Yanofsky noticed that the cell was able to sense how much tryptophan was present and alter the transcription process accordingly, halting it if necessary. This indicated that mRNA was not…
Read More
coli and Bacillus subtilis. While conducting experiments focused on discerning the mechanisms of this process in 1981, Yanofsky noticed that the cell was able to sense how much tryptophan was present and alter the transcription process accordingly, halting it if necessary. This indicated that mRNA was not…
Read More