Updated: Sep 4, 2020
Description & Signifigance
Bacillus licheniformis is a bacterium that is commonly found in soil and bird feathers. Birds that tend to stay on the ground more than the air (i.e. sparrows)and on the water (i.e. ducks) are common carriers of this bacterium; it is mostly found around the bird's chest area and back plumage. B. licheniformis is part of the subtilis group along with Bacillus subtilis and Bacillus pumilus. These bacteria are commonly known to cause food poisoning and food spoilage. B. licheniformis also is known for contaminating dairy products. Food borne outbreaks usually involve cases of cooked meats and vegetables, raw milk, and industrially produced baby food contaminated with B. licheniformis.
This bacterium, although detrimental, can be modified to become useful. Researchers are trying to turn bird feathers into a nutritious livestock feed by fermenting non-digestable proteins on bird feathers with B. licheniformis. There is also research about the possibility that B. licheniformis causes changes in color in birds' feathers; this will provide information on the evolution of molting. Also, cultures of B. licheniformis are made to retain its protease, which is in turn used in laundry detergent.
The complete nucleotide sequence of Bacillus licheniformis consists of the ATCC 14580 genome, which has a circular chromosome of 4,222,336 bp (base pairs) which contains 4,208 predicted protein-coding genes (average size of 873 bp), 7 rRNA operons, and 72 tRNA genes. The GC content is 46.2% and no plasmids were detected.
The chromosome of B. licheniformis has large regions that are similar to Bacillus subtilis and Bacillus halodurans. Since about 80% of the coding sequence of B. licheniformis contain B. subtilis orthologs, it is considered part of the subtilis group. But, although similar to B. subtilis, they differ in the amount and location of prophages, transposable elements, extracellular enzymes, and secondary metabolic pathway operons.
Cell Structure and Metabolism
Bacillus licheniformis is a rod-shaped, Gram-positive bacterium. It tends to form spores in soil which makes it desirable to be used for the industrial purposes such as the production of enzymes, antibiotics, and small metabolites. It produces a variety of extracellular enzymes that are associated with the cycling of nutrients in nature.
Its optimal growth temperature is 50°C, but it can also survive at much higher temperatures. Its optimal temperature for enzyme secretion is 37°C. This bacterium can survive harsh environments by turning into spore-form; when conditions are good, it will turn back into a vegetative state.
B. licheniformis produces a protease that can survive at high pH levels. This protease is a desired ingredient in laundry detergent due to its ability to be used in low temperatures, which prevents shrinkage and fading colors.
Application to Biotechnology
Bacillus licheniformis is a spore-forming soil organism that contributes to nutrient cycling and has antifungal activity. There is current research on B. licheniformis 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. There have been reports of reproductive failure and mastitis caused by this bacterium in cattle, sheep and swine. It fortunately does not have any detrimental effects on endangered species
Watch our "Function Focused Bacteria for Soil Health Video": https://youtu.be/L7yyeK-UVnA