The beta-lactam antibiotics: past, present, and future.

The discovery and development of the beta-lactam antibiotics are among the most powerful and successful achievements of modern science and technology. Since Fleming's accidental discovery of the penicillin-producing mold, seventy years of steady progress has followed, and today the beta-lactam group of compounds are the most successful example of natural product application and chemotherapy. Following on the heels of penicillin production by Penicillium chrysogenum came the discoveries of cephalosporin formation by Cephalosporium acremonium, cephamycin, clavam and carbapenem production by actinomycetes, and monocyclic beta-lactam production by actinomycetes and unicellular bacteria. Each one of these groups has yielded medically-useful products and has contributed to the reduction of pain and suffering of people throughout the world. Research on the microbiology, biochemistry, genetics and chemistry of these compounds have continued up to the present with major contributions being made by both individual and collaborative groups from industry and academia. The discovery of penicillin not only led to the era of the wonder drugs but provided the most important antibiotics available to medicine. Continued efforts have resulted in the improvement of these compounds with respect to potency, breadth of spectrum, activity against resistant pathogens, stability and pharmacokinetic properties. On the research front, major advances are being made on structural and regulatory biosynthetic genes and metabolic engineering of the pathways involved. New semisynthetic compounds especially those designed to combat resistance development are being examined in the clinic, and unusual non-antibiotic activities of these compounds are being pursued. Although seventy years of age, the beta-lactams are not yet ready for retirement.