NUCLEIC ACIDS

Their Chemical Properties and Physiological ConductIn the year i868 Friedrich Miescher [1868] undertook a chemical examination of pus cells. Surgical bandages, secured from a neigh bouring clinic, were extracted with a dilute solution of sodium sulphate, and the heavy pus cells thus obtained were easily separated from ad herent serum and salt solution by careful decantation. The cells, still intact, were then submitted to the digestive action of artificial gastric juice which dissolved the protoplasm, leaving the more resistant nucleus as an insoluble grey powder, so that cell nuclei free from protoplasm became available for chemical study. Upon treatment of these insoluble nuclei with dilute sodium carbonate a solution was obtained in which acetic acid produced a flocculent precipitate which was found to contain phosphorus and responded to protein colour tests. This substance to which Miescher gave the name nuclein on account of its origin was the first known member of what is now a comparatively large class of sub stances obtainable from the nuclei of animal and plant cells. Hoppe Seyler [1871] prepared one from the nuclei of yeast cells, and Kossel [1881] afterwards prepared another from the red-blood corpuscles of birds. All of these nucleins are insoluble acids which form soluble sodium salts. They respond to the protein colour reactions, but difl er from proteins in the phosphorus which they contain and in the resistance which they ofi er to the solvent action of artificial gastric juice.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition.