ENZYME ISOLATED

Shannon News, 30 November 1926, Page 3

ENZYME ISOLATED

BY CORNELL SCIENTIST. ■ ■ ' ' PROBLEM SOLVED.. After nine years of research James B. Sumner, Assistant Professor of Biological Chemistry at.(Cornell Medical College, has solved a problem that lias baffled chemists for a century. He has succeeded, it is stated, in,the isolation and crystallisation of the first enzyme. ' During a part of the time, Dr. Sumner was assisted by Dr. Viola A. Graham and Dr. Charles V. Noback. The enzyme in question is known as urease and occurs in the jack bean, in the soy bean and 'in a gremt many kinds of bacteria. It has been found in the horse-shoe crab and in the lining of the stomach. , Urease is important in the cycle of nitrogen, because it converts the urea that is produced by animals into ammonium carbonate, which is tsed by the plant, usually after conversion of the nitrates by bacteria. Chemists have been attempting to purify enzymes for nearly a century, but up to the time of Dr. Sumner’s discovery no enzyme had even been prepared in pure condition and the chemical nature of enzymes was entirely unknown. A prominent worker in the field, Dr Richard Wilstatter of Germany, recently declared that enzymes belonged to no known group of chemical substances. For the benefit of the layman, it may be stated that an enzyme (the word means “in yeast") is a substance elaborated by plants, animals or micro-organisms that accelerates chemical reactions without itself being used up in the process. In other words, an enzyme is a catalyst df a special sort. It is extremely unstable, and of collodial nature. Urease has been prepared by Dr. Sumner as octahedral crystals that are slightly larger in diameter than Tiuman blood corpuscles. The crystals are protein and belong to a class known as globulins. They are able to transform their own weight of urea into ammonium carbonate every 1.4 second at room temperatures. ' ' "