Benzylpenicillin

The “wonder drug” penicillin is actually a group of drugs that have different functional groups on one of the side chains on the bicyclic core. In 1928, Scottish biologist Alexander Fleming isolated the first specific form of penicillin from Penicillium fungi; the compound is known variously as benzylpenicillin, penicillin G, or benzylpenicillinic acid. For this achievement, Fleming shared the 1945 Nobel Prize in Physiology or Medicine.

The free acid benzylpenicillin is only sparingly soluble in water; but even worse, it is inactivated by water. Thus, the articles of commerce are its sodium and potassium salts, which are much more water-soluble and stable in solution.

By the beginning of World War II, penicillin had been developed into antibacterial drugs that could be mass-produced. At the time of the Normandy invasion in 1944, more than 2 million doses had been made. Penicillin may have saved as many as 100,000 lives during the war.

Much more recently, it was discovered that some soil bacteria readily consume penicillin and other β-lactam antibiotics. Biologist Gautam Dantas and his team at Washington University (St. Louis) hypothesized that bacteria engineered to maximize β-lactam consumption capacity could be used to remediate antibiotic-contaminated soils.

The researchers created a strain of Escherichia coli that uses penicillin as its only carbon source. The downside, however, is that other organisms might also acquire the degradation genes and become resistant to penicillin.