Novosphingobium aromaticivorans is a gram-negative aerobic bacterium that is well known for its ability to degrade phenolic structures. N. aromaticivorans has been reported to trigger the development of primary biliary cirrhosis because it expresses proteins that have high homology with human pyruvate dehydrogenase component (PDC-E2), which can act as an immunological trigger for T cell-mediated tissue destruction.