Bacillus Clausii is Gram-positive, motile, spore-forming and like most of the Bacillus bacteria, it is rod-shaped. Colonies of Bacillus Clausii form filamentous margins that appear cream-white in color. Bacillus Clausii is alkaliphilic and produces a class of subtilisins known as high-alkaline proteases. The protease from Bacillus clausii strain 221, the H-221 protease, was the first enzyme to be identified in an alkaliphilic Bacillus. The alkaliphilic nature of the organism has also proved it to be useful in preventing and treating various gastrointestinal disorders as an oral bacteriotherapy. This Bacillus Clausii can be found in many alkaline environments, including soil and marine habitat.
Bacillus clausii bacterium is naturally found in the soil where it can reduce nitrate to nitrite. The use of nitrite to become other reduced forms of nitrogenous compounds is possible, and some bacteria such as Pseudomonas aeruginosa are capable of the complete reduction of nitrite. But the extent of nitrate reduction has not been studied thoroughly in Bacillus clausii. A possible relationship with other organisms that use nitrites therefore exist.
