Physical Description of Lactobacillus Acidophilus

Lactobacillus acidophilus bacteria live in the small intestine and vagina and protect against infectious invaders. Among the most common probiotics, or healthy bacteria, Lactobacillus acidophilus is generally considered safe for medicinal use.

History

• Scientists isolated and characterized Lactobacillus acidophilus in 1970, and marketing for its health benefits began mid-decade.

Morphology

• Lactobacillus acidophilus is a bacillus, which means it's shaped like a rod. The NCFM strain of Lactobacillus acidophilus contains 1,993,564 nucleotides, or the molecules that form the bacteria's basic structural units (DNA and RNA).

Size

• Lactobacillus acidophilus measures only 2 to 10 micrometers, which is approximately the size of a red blood cell. (Red blood cells measure about 8 micrometers).

Gram Test

• The Gram test helps determine the content of a bacteria's cell wall. Lactobacillus acidophilus is Gram positive, which means it contains high amounts of peptidoglycan. Peptidoglycan is a mesh-like substance that gives a cell wall structure and shape.

Growing Conditions

• Lactobacillus acidophilus thrives in warm, acidic environments without oxygen. Its optimal growing temperature is about 40 degrees Celsius, the temperature of a hot summer day.

Benefits

• Lactobacillus acidophilus produces vitamin K and lactase (an enzyme that helps you digest milk). This bacteria also produces acidolin, bacteriocin, lactocidin and other anti-microbials, which kill off--or at least stop the growth of--infectious invaders.