In 1945, Waksman, Schatz, and Bugie published theirwork on streptomycin, the first antibiotic active againstthe tuberculosis bacterium and also valuable in the fightagainst bacterial meningitis. Waksman received theNobel Prize for this accomplishment in 1952, and withroyalties turned over to the Rutgers University by agenerous Merck administration, he was able to build theWaksman Institute of Microbiology. With his studentLechevalier, Waksman reported on the discovery ofneomycin in 1948 and candicidin in 1953. Discovery of25 additional antibiotics by the Waksman group followed.Neomycin, an aminoglycoside produced byStreptomyces fradiae, serves as a topical antibacterialagent, and the polyene candicidin, made by Streptomycegriseus, became a topical antifungal product. The discoveriesof the Waksman group stimulated antibioticdrug discovery efforts internationally from 1948 untiltoday. The selective action exerted on pathogenic bacteriaand fungi by these microbial secondary metabolitesushered in the antibiotic era and for many years, wehave benefited from this remarkable property of wonderdrugs such as the penicillins, cephalosporins, tetracyclines,aminoglycosides, chloramphenicol, macrolides,and many others [13]. The successes were so impressivethat these antibiotics were virtually the only drugs utilizedfor chemotherapy against pathogenic microorganisms.By 2002, over 22,000 bioactive compounds hadbeen discovered from microbes. These included 20,000antibiotics, mainly produced by the actinomycetes(45%), fungi (38%), and unicellular bacteria (17%,chiefly by Pseudomonas and Bacillus) [6]. Of the actinomyceteantibiotics, about 80% are made by membersof the genus Streptomyces. One microbe usually producesmore than one compound. For example, a gentamicin-producingstrain of Micromonospora forms 50isolatable secondary metabolites [7].
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