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glutamic acid

(Encyclopedia)CE5 glutamic acid glo͞otămˈĭk [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer occurs in mammalian proteins. Like aspartic acid, glu...

Lipmann, Fritz Albert

(Encyclopedia)Lipmann, Fritz Albert, 1899–1986, American biochemist, b. Germany, grad. Univ. of Berlin (M.D., 1922; Ph.D., 1927). He emigrated to the United States in 1939 and became a citizen in 1944. In 1941 he...

coenzyme

(Encyclopedia)coenzyme kō-ĕnˈzīm [key], any one of a group of relatively small organic molecules required for the catalytic function of certain enzymes. A coenzyme may either be attached by covalent bonds to a ...

glycolysis

(Encyclopedia)glycolysis glīkŏlˈĭsĭs [key], term given to the metabolic pathway utilized by most microorganisms (yeast and bacteria) and by all “higher” animals (including humans) for the degradation of gl...

Hartwell, Leland Harrison

(Encyclopedia)Hartwell, Leland Harrison, 1939–, American cell biologist, b. Los Angeles, Ph.D. Massachusetts Institute of Technology, 1964. He is a professor at the Univ. of Washington (1968–) and since 1997 ha...

Julian Day calendar

(Encyclopedia)Julian Day calendar, system of astronomical dating that allows the difference between two dates to be calculated more easily than conventional civil calendars with their uneven months. It was devised ...

Mottl, Felix

(Encyclopedia)Mottl, Felix fāˈlēks mōˈtəl [key], 1856–1911, Austrian conductor. He assisted Wagner in preparing the first Bayreuth Festival, at which he conducted the Ring cycle. Mottl conducted (1881–190...

nucleosynthesis

(Encyclopedia)nucleosynthesis or nucleogenesis, in astronomy, production of all the chemical elements from the simplest element, hydrogen, by thermonuclear reactions within stars, supernovas, and in the big bang at...

snowmobile

(Encyclopedia)snowmobile, vehicle designed to travel over snow, ice, and similar surfaces that offer limited traction and weight-supporting capability. As the performance of the vehicle depends to a large extent on...

business cycles

(Encyclopedia)business cycles, fluctuations in economic activity characterized by periods of rising and falling fiscal health. During a business cycle, an economy grows, reaches a peak, and then begins a downturn f...