Higher order taxa:
Bacteria; Firmicutes; Bacilli; Lactobacillales; Lactobacillaceae; Lactobacillus crispatus
Lactobacillus crispactus. L. bulgarius. L acidophilus, L. thermophilus
Description and Significance
Lactobacillus is an anaerobic, gram positive, rod shaped bacteria. Lactobacillus crispatus is beneficial bacteria found in the vaginal tract, intestinal regions, and gut flora. This species has the ability to produce numerous antimicrobial compounds and helps to maintain an acidic environment in its host. This environment allows for the proper maintenance of a healthy pH, as well as preventing the formation of foreign gram negative and gram positive bacteria from forming. L. crispatus has been discovered to adhere to epithelial cells via proteins, allowing for the protection and prevention of other pathogenic microbes from adhering to the host cell walls.
The exact carbon content and genome sequence of L. crispatus is not well known, although after metabolizing it does produce ( H2O2) hydrogen peroxide.
Cell Structure and Metabolism
The structure of Lactobacillus crispatus is a rod shaped bacteria that uses homofermentative metabolism; it converts lactose or other sugars into lactic acid. It is a hydrogen peroxide producing microbe that uses lactic acid as its form of growth product. This anaerobic microbe uses these fermentative processes to create its growth product lactic acid; allowing for the protection of its host micro biota. The cell preforms its adhesion to the host organism’s linings using three components: amino acid composition, Lipoteichoic acid, and S layer proteins. The amino acid composition varies although it mainly facilitates via hydrophobic residues. Lipoteichoic acid aides the adherence of the Lactobacilli due to its presence of cytokine receptors, these receptors contain both probiotic and anti-inflammatory responsibilities. Extra cellular proteins such as CbsA benefit L. crispatus by mediating binding of the microbe to the host micro biota with collagen and laminin.
The species L. crispatus is a probiotic found in the intestinal tract, vaginal tract, and gut flora of humans. It grows optimally between the temperatures of 30 and 40 degrees Celsius. L. crispatus present in the vaginal tract is useful for maintaining a balanced flora, while providing preventative measures against bacterial vaginosis. In the gut flora, L. crispatus is found to promote healthy digestion due to the production of enzymes. The Lactobacilli species can be replenished into these tracts by the way of supplement ingestion. L. crispatus is not the only lactobacillus species found although it is the most prevalent in the vaginal tract.
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