318 6. INTERACTIONS OF INHIBITORS WITH ENZYMES 



ground. It is not advisable tiiat the inherent complexities of intermolecular 

 reactions be minimized for the problems must be faced and progressively 

 solved. The development with respect to enzyme inhibition must progress 

 through the interplay of two principal lines of investigation: the theo- 

 retical and experimental study of intermolecular forces between simple mol- 

 ecules of biological significance on the one hand, and the accumulation 

 and interpretation of much quantitative data from enzyme inhibitions 

 on the other. Only by the full utilization of the results of both approaches 

 can a more accurate and meaningful understanding on the molecular level 

 be attained. Many investigations are concerned only with whether an inhi- 

 bitor acts on the system or not and such studies contribute nothing to the 

 problem of mechanisms. It is somewhat laborious to vary concentrations 

 and various factors, to obtain accurate data and to submit these data 

 to a thorough analysis, bearing in mind all of the possibilities in mechanism 

 and the many types of forces that must be considered as contributing to 

 the total binding energy, but once the interest of the investigator is attuned 

 to molecular levels it is very rewarding. The study of enzyme inhibition is, 

 of course, only one aspect of the general problem of the interactions wich 

 proteins and advances in the general field must be applied to the special 

 phenomenon of inhibition to achieve maximal progress. As in any scientific 

 field, the greater our knowledge of the basic mechanisms, the more readily 

 we can predict interactions and develop enzyme inhibitors of high potency 

 and specificity for use in both research and medicine. 



It must be admitted that the state of knowledge of enzyme interactions 

 is relatively rudimentary, as it is in the field of molecular interactions 

 in general. The author has probal)ly exceeded the limits of certainty in 

 some cases and stated some doubtful points with more conviction than is 

 justified. This has been done in the interests of clarity but apologies must 

 be made not only for such overstatements but also for the sins of omission, 

 because of which important reports have been unrecognized or here un- 

 recorded. If the inaccuracies stimulate others to any profitable emotion or 

 to more rigorous solutions of the problems, we shall be indebted to these 

 inaccuracies, although I regret them. 



