THREE DECADES PROGRESS IN MICROBIOLOGY 



put forward which seem suitable to free biochemistry from this special 

 vitalistic aspect. 



I have already remarked that the greater part of the step-reactions 

 in the catabolic breakdown of carbohydrates are of the equilibrium 

 type. This implies that the addition of many of the intermediate pro- 

 ducts to the cell must automatically lead to a partial reversal of the 

 breakdown process, i.e., to the synthesis of the carbohydrate. The real- 

 isation of this situation made Cori succeed in the long-pursued enzym- 

 atic synthesis of glycogen and starch starting from glucose- 1 -phosphate 

 or Cori-ester. Perhaps still more spectacular has been the successful 

 solution found by Doudoroff and his co-workers for the problem of the 

 synthesis of saccharose, a problem which generations of organic chem- 

 ists have been unable to solve. With the aid of a phosphorylase pre- 

 paration obtained from some common bacterium saccharose was read- 

 ily produced from a mixture of Cori-ester and fructose. 



Now these examples of the successful demonstration of the formation 

 of typical assimilatory products like glycogen and saccharose may 

 perhaps not be so very impressive, because of the relative complexity 

 of the substrate - Cori-ester - from which these syntheses start. But 

 there is no doubt that by applying the necessary biocatalysts they 

 could as successfully be accomplished when starting with various much 

 simpler compounds, such as for instance phosphopyruvate. 



Since, however, in these cases the potentials of substrates and syn- 

 thetical products are very much on the same level they do not rep- 

 resent clear cases of energy transfer necessary for the formation of 

 anabolic products of high potential as referred to earlier. 



Now it is very satisfactory that also in the elucidation of the mech- 

 anism of such anabolic reactions important advances have been made. 

 These advances are for a great deal due to three scientists well-known 

 in Copenhagen so that it will suffice to give only a very brief review of 

 their findings. The development of our insight into this matter has 

 started with Lundsgaard's discovery of the anaerobic phosphocreatine 

 breakdown during a lactic acid muscle contraction, and the coupling 

 of the resynthesis of this compound with lactic acid formation in glyc- 

 olysis. A second well-defined instance of the coupling of an oxidation 

 with phosphate uptake was discovered by Meyerhof and his co-workers 

 in the oxidation of phosphotriose as a step-reaction in carbohydrate 

 breakdown. They showed that this oxidation led to the formation of 



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