( 2) 



f n verted 

 canesugar 



Chemistry. - "Ertzj/riK^ Action.'' By Dr. H. P. Barendrfcht. 

 (Communicated by Prof. .T. M. van Bemmelkn). 



(Cüminunicaled in the meeting of April 23, 1904.) 



The follow iiiu is n pi-eliiiiiiuiry coniinuiiicadoji of the writer's 

 researches on eir/.ynie action.^ duriiig the last \\\o years. 



From the connnencement it has been the writer's object to ascer- 

 tain in liow far a continued research of simi)le enzyme actions might 

 confirm the hypothesis that the enzymes exert their catalytic action 



l»y radiation. This hypothesis ori- 

 ginated iji the peculiarity of the 

 action of the enzymes which 

 distinguishes this action so sharply 

 from that of tlie acids. A graphic 

 representation of the action of the 

 same (piautity of acid or enzyme 

 in the same time on sugar solut- 

 ions of different concentrations 

 renders this difference very per- 

 ceptible. 



Fig. 1 gives a scheme of the 

 _ inversion bv acids. The line wliich 



Iniliul concentration ol' tlii> canesugar 



iM-. i. 



Invorteil canesiijiar. 



remains straight indicates that the 

 quantity of inverted canesugar 

 i-emains proportionate to the initial 

 concentration. 



— — . In the case of enzymes the 



Initial concentration oC tlie canesugar. general course is represented by 

 ^''^'' -■ fig. 2. In the inversion of cane- 



sugar for instance, the line remains straigld up to an initial con- 

 centration of 0.i"/„ ; it then inflects towards the -t' axis and runs 

 henceforth parallel to this. 



This characteristic behaviour of tlie enzymes is now at once 

 explained l)y the radiation theory which will be further developed. 

 Let us, for the sake of convenience, confine ourselves to the action 

 of invertin and let us suppose we have two solutions containing, 

 respecti\ely, 20'^/,, and 107„ of canesugar. In the 207„ solution tlie 

 radiation from each enzyme i)article will l)e comparatively soon 

 absorbed by the surrounding molecules of canesugar ; in the lO'/o 

 solution the sphere to which the enzyme action can extend will 

 be larger. So long as the solution is sufficiently concentrated to 

 finalh absorb b> a sugar molecule all radiation emanating from an 



