The Biochemistry 

 of Ferritin 



ABRAHAM MAZUR 



An interpretation of biological phenomena in terms of chemical 

 structure or chemical interaction remains a basic goal of biochemistry. 

 Progress along these lines has been made with compounds of low 

 molecular weight and relatively simple structure. Examples are the 

 reactions involved in metabolism of carbohydrates, fatty acids, and 

 amino acids; these reactions can now be written in great detail and 

 their mechanisms have been revealed. Such advances have been aided 

 in no small measure by the relative ease with which these compounds 

 can be obtained in a pure state and by the simplicity of the criteria for 

 their purity. 



The difficulties are greatly multiplied for macromolecules such as 

 proteins, where the criteria for purity are themselves often in question. 

 Progress in relating function to chemical structure is currently in evi- 

 dence among one group of proteins, the enzymes; their activities are 

 measured by methods which are relatively simple, quick, and quanti- 

 tative. However, for proteins endowed with hormonal activity, our 

 understanding is more limited. Because of the nature of the tests for 

 physiological activity, the isolation of protein hormones in a pure state 

 has been slow and studies relating their activity to structure are ham- 

 pered by lack of sufficient amounts of the protein, lack of accuracy of 

 the determination, and the length of time required to obtain an ade- 

 quate measure of activity. An additional factor which complicates 

 the study of protein hormones is the fact that the observed activity in 

 an animal, organ, or tissue is usually the end result of a series of re- 

 actions which occur between the administration of the protein and the 

 final observation of functional activity, with no evidence concerning 

 the nature of the initial or intermediate reactions. 



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