On the Presence of a Glycolytic Enzyme in Muscle. 



323 



may be said that their properties are precisely parallel, the constants 

 and curves being merely moved on to a slight extent by the replace- 

 ment of sulphur by selenium without disturbing their relationships. 



" On the Presence of a Glycolytic Enzyme in Muscle." By 

 Sir T. Lauder Brunton, M.D., F.K.S., and Herbert Bhodes, 

 M.B. Beceived May 7 —Bead May 23, 1901. 



It was found by Claude Bernard as well as by Ludwig and Gene- 

 rich that the blood which issued from a contracting muscle contained 

 less sugar than the arterial blood which entered it. This destruction 

 of sugar during its passage through the muscle might no doubt be 

 partially due to the action of the blood itself upon the sugar, but it is 

 natural to think that it may be due to the action of some glycolytic 

 ferment contained in the muscle itself. An attempt to isolate such a 

 ferment or enzyme was made by one of us (Brunton) in 1873. The 

 attempt was only partially successful. The method employed was that 

 of von Wittich. Some fresh muscle was comminuted, thoroughly 

 mixed with glycerine and allowed to stand for many days. The 

 glycerine extract was then filtered off. When some of this extract was 

 mixed with a solution of glucose and allowed to stand for some hours 

 at the temperature of the body, a distinct diminution was observed 

 in the amount of glucose, while a control specimen of the glucose 

 treated in the same way with a similar quantity of pure glycerine 

 showed no diminution. The presence of a glycolytic substance was 

 thus clearly shown. 



An attempt was made to isolate out a glycolytic enzyme from 

 the glycerine extract by diluting the glycerine and mixing it with 

 alcohol. A scanty white precipitate was obtained, but the precipitate 

 exhibited little if any glycolytic power. Numerous experiments 

 having failed to isolate the ferment, they were not published, and 

 the result was only briefly noticed in a foot-note to a paper on 

 Diabetes in the 'British Medical Journal' of February 21st, 1874. 

 At that time, one of us (Brunton) administered raw meat to diabetic 

 patients in the hope of supplying sufficient glycolytic ferment to 

 enable the sugar to be better utilised in the body, and also tried 

 the administration of glycerine extract of muscle. The success 

 attending these attempts was not, however, sufficient to encourage 

 the persistent use of this means of treatment, and the attempt to 

 isolate a glycolytic ferment was abandoned for a good many years. 



The success of Buchner in separating an alcoholic ferment from yeast 

 by means of great pressure gave promise of possible success in 

 separating a glycolytic ferment from muscle by similar means, and by 



