BIOCHEMISTRY OF MICRO-ORGANISMS 



117 



If it is remembered that the study of 

 these synthetic processes is as yet limited 

 to a very small number of investigations, 

 carried out only during the last three 

 years, it is not surprising that our knowl- 

 edge is still most imperfect and in so in- 

 cipient a stage. Considering the develop- 

 ment in the other fields of biochemical 

 research, there is, however, reason to be- 

 lieve that the anabolic phase of metabolism 

 w^ill soon become as fruitful a field of in- 

 vestigation as catabolism has been during 

 the past quarter of a century. I should 

 like to stress the importance of micro- 

 organisms for such studies; the variety of 

 organisms is so large, and one may expect 

 to find so many individual differences that 

 the approach from the viewpoint of com- 

 parative biochemistry promises a vastly 

 increased possibility to survey the ele- 

 mentary processes. 



Here I may end this cursory review of 

 the basic principles upon which biochem- 

 ical thought rests today. I hope to have 

 succeeded in showing how a study of the 

 behavior of micro-organisms has aided in 

 the formulation of these principles; how 

 "comparative biochemistry" has come to 

 occupy an important position. 



Science rests upon the firm foundation 

 of observation and experimental results, 

 i.e., upon reproducible facts. But the 

 progress of science, even though bound to 

 the recording of such observations, is itself 

 due to the gradual development of hy- 

 potheses. It is the great generalizations in 

 which observational data on many appar- 

 ently unrelated groups of phenomena are 

 linked together into comprehensive points 

 of view — our working hypotheses and 

 theories — that mark the stepping stones by 

 which our scientific outlook has developed. 



A century ago Schwann, in formulating 

 one of these broad generalizations, com- 

 mented upon the fortunate circumstances 

 which had led to an increasing unification 

 of the scientific outlook. This unification 

 has not come to a standstill; the side-by- 

 side growth of the various branches of 

 scientific endeavor and discovery has led, 

 and is still leading, towards a mutual 



fertilization, and we can unhesitatingly 

 subscribe today to Schwann's statement 



(1837) : 



Es ist ein wesentlicher Vorzug unseres Zeitalters, 

 dass die einzelnen Disziplinen der Naturwissen- 

 schaften in immer innigere Vereinigung miteinan- 

 der treten, und gerade dieser weehselseitigen 

 Durehdringung und Erganzung verdanken wir 

 einen grossen Theil der Fortschritte, welche die 

 Naturwissenschaften in der neuesten Zeit gemacht 

 haben. 



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