PREFACE 



systems and materials has been slower but still impressive. 

 Kinetic analysis of enzymes has graduated to a very sophisticated 

 and exact science which has been taken over by specialists well 

 grounded in physical chemical theory and practice. The con- 

 cepts of energy transformations and of the high-energy bond have 

 lost their earlier primitive character and are now couched in 

 the more rigorous language of quantum mechanics and valency 

 theory. The interpretation of the properties and behavior of 

 proteins and other macromolecules has now attained a high 

 degree of precision. Certainly the molecular picture of how 

 myosin contracts is constructed in terms which would have been 

 inconceivable even ten years ago. 



It now appears that biochemistry has reached a stage in 

 development where fragmentation cannot be avoided. The 

 choice now lies between chemistry and physiology since the 

 meso area has all but disappeared. The classical areas of bio- 

 chemistry such as nutrition, vitamins, minerals, enzymology, 

 metabolism, and the chemical structure of biologically im- 

 portant compounds are becoming leaner and leaner, and the 

 focus is shifting inexorably either to more chemical and molecular 

 aspects or to the broader and as yet unsolved physiological 

 problems. 



It is at present quite clear which chemical problems will 

 dominate the scene in the next few years. Certainly efforts will 

 be redoubled to determine the exact stereochemistry of protein 

 molecules after the spectacular success of the a helix concept. 

 Such efforts will be paralleled by companion efforts to elucidate 

 the structure of the active groups of enzymes. Once an under- 

 standing of the architecture of the active groups of enzymes has 

 been attained then the old problem of the mechanism of enzyme 

 action will be in line for renewed assault. The nature of the 

 forces and bonds which lead to enzyme-substrate interactions is 

 an area of investigation which badly needs sparking by new 

 leads. 



The real frontier areas of biochemistry now reach to the 

 borderlines of physiology, genetics, cytology, medicine, and 



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