Domain: Bacteria
       Kingdom: Bacteria
       Phylum: Firmicutes
       Class: Bacilli
       Order: Lactobacillales
       Family: Lactobacillacea
       Genus: Lactobacillus
       Species: delbruekii
       Subspecies: bulgaricus

Have you ever ate yogurt? Well then you have consumed the bacteria Lactobacillus bulgaricus.  Lactobacilli are bacteria are commonly known for producing lactic acid.  The lactic acid from Lactobacillus bulgaricus is used in the production of yogurt.  The bacteria can also help people that are lactose intolerant. It will break down the lactose since they lack the enzyme, lactase, which normally breaks lactose into simpler sugars. To aid in human health they are also probiotics, which are beneficial bacteria in the digestive tract.  They are rod-shaped and found in pairs or in long chains as seen in the photo above.  Lactobacillus bulgaricus was first discovered in 1905 by a Bulgarian doctor, Stamen Grigorov, and named after the country. Later in 1983 studies done by Weiss, Schillinger, and Kandler changed the taxonomy of Lactobacillus bulgaricus.  It soon became a subspecies to Lactobacillus delbrueckii, along with Lactobacillus lactis, and Lactobacillus delbrueckii.