Veillonella are gram-negative anaerobic cocci. This bacterium is well known for its lactate fermenting abilities. They are a normal bacterium in the intestines and oral mucosa of mammals. In humans they have been rarely implicated in cases of osteomyelitis and endocarditis, for example with the species Veillonella parvula.
Lactate → acetate + 2 propionate + CO2 + H2O