Companies spend huge resources going to the far reaches of the Earth to search for the next blockbuster. But we need look no further than our own intestines, which are populated with thousands of bacterial species that are constantly producing and releasing small, bioactive molecules.
Small molecules—the bread and butter of pharmaceutical companies—are compounds of low molecular weight (under 3,000 daltons) and diverse chemical composition. Examples of such molecules are the steroid and small-peptide hormones of higher organisms, with a molecular weight around 300 daltons, which have many important biological functions. The term hormone (from the Greek: excite, arouse) was coined in 1905 by British physiologist1 Ernest Starling to describe the chemical messengers produced in an organ or gland of the body that travel to distant organs to exert their physiological effects. In humans, the critical functions of small-molecule hormones include modulation of the immune system, the development of sexual ...
