BIOGRAPHICAL MEMORANDA 



a procedure that was patented by Kluyver [Kluyver and Visser 't 

 Hooft, 1 931]. The efficacy of such processes is attested to by the fact 

 that the commercial production of sorbose, an important intermediate 

 stage in the commercial manufacture of ascorbic acid by the Reich- 

 stein method, is universally accomplished with cultures of this or- 

 ganism. 



But the discovery of A. suboxydans was even more important because 

 of the consequences it entailed for the evolution of Kluyver's bio- 

 chemical outlook. First of all, it had become apparent that the phys- 

 iological group of the vinegar bacteria comprizes a number of repre- 

 sentatives that are distinguishable by the extent to which they can 

 oxidize various substrates. And the possibility of arranging these rep- 

 resentatives in order so that the metabolic end products of one type 

 can still serve as oxidation substrates for the subsequent ones further 

 suggested that generally the stepwise oxidation of substrates might be 

 analyzed with the aid of such a series of strains which would permit the 

 isolation of the consecutive oxidation products from cultures with pro- 

 gressively increasing oxidative capacity. Thus came about the desire 

 to study in a comparative manner the biochemical activities of va- 

 rious groups of micro-organisms. 



That Kluyver anticipated a considerable clarification of our under- 

 standing of metabolic processes from such studies is clearly evident 

 from the lecture he delivered before the Netherlands' Chemical So- 

 ciety in 1924. The major part of this lecture on the 'Unity and diversity 

 in the metabolism of micro-organisms' was devoted to a discussion of 

 the diversity; it could hardly have been otherwise because so little 

 could be said at that time about a possible unity. Nevertheless, this 

 aspect was also broached, and two different approaches were reviewed 

 in some detail, viz., the energetic and the chemical ones. It is un- 

 necessary to summarize the contents of this lecture which is included 

 in this volume; suffice it to say that it illustrates the primitive state of 

 understanding of biochemical phenomena in general. But it may not 

 be superfluous to emphasize Kluyver's insistence on the unifying effect 

 that energetic considerations could exert on our interpretation of bio- 

 chemical processes, equating, for example, all known cases of the so- 

 called dissimilatory reactions, fermentative as well as oxidative, inas- 

 much as they represented the mechanisms whereby energy is made 

 available for the synthetic or assimilatory, and hence energy-requiring 



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