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MICROBES—tiny organisms too small to be seen with the naked eye—have altered human history. Life forms such as bacteria, yeasts, and molds can cause sickness or restore health, and help produce foods and beverages.

Scientists, in partnership with industry, have developed techniques to harness…
CONTINUE to INTRODUCTION Graphic illustrations of various microbes numerically numbered
DNA iconAll organisms, from microbes to humans, are governed by the genetic code embedded in their DNA. In the 1970s, scientists inserted a human gene into the genetic material of a common bacterium. This so-called “recombinant” microorganism could produce the protein encoded by the human gene…
CONTINUE to TINKERING WITH DNA Microphotograph of two E. coli bacteria exchanging DNA through conjugation.  Four views of E. coli bacteria by scanning electron microscope.
hormone iconHormones are complex molecules that regulate vital functions, including growth and development. In humans and animals, hormones are produced in glands and organs such as the pituitary, thyroid, and pancreas…
CONTINUE to HARVESTING HORMONES Drawing of a cutaway view of the inside of a human male head in profile.  Inset shows a close up of the pituitary gland and surrounding area.
penicillin iconMicrobes are equipped with defense mechanisms to help ensure their survival. Penicillium, the bluish-green mold that grows on stale food, produces a substance that has the power to kill its bacterial competition. Many of these bacteria are also deadly to humans.…
CONTINUE to MAKING “YELLOW MAGIC” A woman seated at a laboratory bench examines a petri dish under a magnifying glass.  In the background a man examines an industrial fermentation tank.
penicillin iconHumans and animals have natural defense systems that produce antibodies in the blood to combat bacteria and other harmful substances invading the body. In the late nineteenth century, scientists investigating this immune response in animals developed new methods…
CONTINUE to LIVING FACTORIES Four men in white smocks extract blood from two horses in a stable.
fermentation iconBeer making is an old technology that relies on microorganisms. Brewers, however, barely knew of the existence of microbes, much less the critical role they played in their livelihood. Problems encountered in beer production, motivated scientists to study the secrets…
CONTINUE to THE BREWING MYSTERIES A man stands next to a large cylindrical beer vat and gazes into the vat through a small opening in the conical cover.

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