kluyver's contributions to microbiology and biochemistry 



Jensen's previously proposed genus, Propionibacterium. But this in- 

 vestigation had also indicated a close morphological resemblance be- 

 tween these organisms and several other types of bacteria, such as the 

 lactic acid-, the coryne-, and the mycobacteria. All these organisms 

 can be characterized as non-sporeforming, Gram-positive, and per- 

 manently immotile bacteria. This in turn had suggested the possibility 

 of establishing, in addition to the two major morphological groups 

 recognized by Orla-Jensen, a third one for these immotile organisms. 



These developments resulted, in 1936, in a fairly elaborate attempt 

 to formulate the basic ideas on the classification of bacteria that had 

 gradually taken shape. The timing was shrewd; at the International 

 Congress for Microbiology scheduled to meet in London later during 

 that year, the International Committee for Nomenclature and Classi- 

 fication of which Kluyver was a member would thus be in a position to 

 take cognizance of the proposals, elaborated if necessary by Kluyver 

 himself. Because the paper has been reprinted in this volume it is not nec- 

 essary to discuss it in detail; suffice it to say that it was felt to represent 

 a first step in organizing the Eubacteria in a manner somewhat com- 

 parable to that in which Mendelejeff had arranged the chemical el- 

 ements, and with the same advantage of indicating the potential 

 existence of groups of bacteria with combined morphological and 

 physiological properties not as yet encountered ; if discovered, these 

 could immediately be incorporated in the system in their appropriate 

 places. The recent discovery of polarly flagellated bacteria with a 

 fermentation pattern like that of the coli-group of organisms, and for 

 which Asai et al. [1956] have aptly proposed the generic name, Kluy- 

 vera, testifies to the usefulness of the approach. So do several generic 

 names, created since 1936, and based on the same principles, such as, 

 for example, Methanobacterium and Butyribacterium. 



The simple guidelines employed in 1936 were adequate to achieve 

 a reasonably satisfactory subdivision of those bacteria that are charac- 

 terized by an obligatorily or facultatively fermentative metabolism, be- 

 cause it is easy to distinguish between the diverse and specific fermen- 

 tation patterns. But a subdivision of bacteria with a strictly oxidative 

 type of metabolism could not then be accomplished by a comparable 

 approach; hence the corresponding genera were less satisfactorily 

 defined. Much has meanwhile been learned about patterns of oxi- 

 dative metabolism which suggests that an imaginative use of this in- 



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