1853-1938

Danish physician and pharmacologist who developed the "Gram staining technique," still used today to identify bacteria as "gram positive" or "gram negative". By modifying an existing method, Gram was able to differentiate bacteria based on their cell wall structure. He taught and practiced internal medicine, and his publications advocated rational pharmacotherapy and a clinical science approach to illnesses and disease. Gram was able to end the use of many ineffective and obsolete therapeutic methodologies, and helped reinvigorate and modernize pharmacology.