The Isolation of a Beta Bios.

Abstract

In 1924 Eddy, Kerr and Williams 1 reported the isolation of a crystalline Bios M.P. 223. As tests of the physiological activity of this product proceeded, it became evident that this substance alone could not account for all the yeast growth stimulatory power of its source, yeast autolyzate. Search was therefore begun for another bios and for convenience Bios M.P. 223 will be referred to hereafter as Alpha-bios. By manipulation of the yeast autolyzate it has now been possible to fraction it into at least 3 specifically distinct bios-containing fractions. One fraction yields a homogenous product not hitherto described and which is here designated as Beta-bios. A third fraction yields a concentrate whose behavior toward precipitants suggests Lucas and Miller's Bios II 2 and which we will call here Gamma-bios.

The evidence of the existence of Beta-bios which led to the development of the fractionation methods for its isolation was first obtained by studying the behavior of yeast autolyzate and Alpha-bios solutions under electrodialysis. Using a 14 compartment carbon cell with parchment paper septa and yeast autolyzate, yeast stimulatory activity was sharply concentrated in 2 separate compartments of quite different pH. No such separation occurred when the cell was filled with pure Alpha-bios solution.

The detailed method of fractionation will be reported later. The essential feature of the separation of Beta-bios is the formation of an insoluble barium salt of this substance preliminary to the separation of Alpha and Gamma bioses. This barium salt is then decomposed with sulfuric acid. Basic impurities are eliminate8 by silver and mercuric sulfate and phosphotungstic acid. Non-nitrogenous acids are removed by extraction with acetone.

The Beta-bios isolated by our procedure is very hygroscopic. When dehydrated with acetone and the aid of the vacuum desiccator it is a fine white granular powder decomposing at 100° C. on prolonged heating.