Lactobacillus acidophilus

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Lactobacillus acidophilus
Scientific classification
Domain: Bacteria Phylum: Firmicutes Class: Bacilli Order: Lactobacillales Family: Lactobacillaceae Genus: Lactobacillus Species: L. acidophilus
Binomial name
Lactobacillus acidophilus

Description and significance

Lactobacillus acidophilus is a species of gram-positive bacteria commonly used in dairy production. L. acidophilus is also one of the most common forms of probiotics, which are "friendly bacteria". L. acidophilus is found in the human and animal gut, mouth, and vagina. It functions as a lactic acid producer, by metabolizing lactose to lactic acid. The acid produced by L. acidophilus can control the growth of the fungus Candida albicans, which is the cause of Oral thrush and vaginal yeast infections. The acid produced can also prevent unwanted organisms living in the gut. L. acidophilus is commonly used in the production of yogurt, where it is labeled as an active or live culture. People that are lactose intolerant are able to digest dairy products containing L. acidophilus better than dairy products without it. Selected strains of L. acidophilus have shown significant reductions of cholesterol in humans, lowering the risk of coronary heart disease.

Genome structure

The complete genome of Lactobacillus acidophilus NCFM contains 1,993,564 nucleotides and has no plasmids. Its average GC content is 34.71% and 1,864 ORFs were predicted. 72.5% of the open reading frames (ORFs) were classified as functional. Several proteins which allowed L. acidophilus to survive in the gut were identified. These proteins included gene clusters that allowed the transport of a diverse group of carbohydrates, including fructooligosaccharides and raffinose. 9 two-component regulatory systems were predicted, which involved in bacteriocin production and acid tolerance.

References

http://www.umm.edu/altmed/articles/lactobacillus-acidophilus-000310.htm [1]

http://jds.fass.org/cgi/reprint/63/5/830.pdf [2]

http://jds.fass.org/cgi/content/abstract/66/5/959 [3]

http://www.jacn.org/cgi/reprint/18/1/43.pdf [4]

http://www.pnas.org/content/102/11/3906.full.pdf+html [5]