WALKER 



effect upon the cell. Our interpretation has been that as multi- 

 plication goes on and virus is produced possessing enzymatic 

 activity, you see then the appearance of enzymatic activity in 

 the cell. This is associated with cell damage, but it would be 

 difficult to decide which is cause and which is effect. 



METCALF: Well, this is perhaps true, but in our case, every 

 time that we demonstrate enzymic competence and show this by 

 enzyme fabrication, we experience a corresponding reduction in the 

 exhibitor content and there is demonstrable damage to the cells. 

 I agree that it is difficult to separate cause and effect, but en- 

 zyme fabrication and cell damage are intimately related. Per- 

 haps this would be a compromise between the two viewpoints. 



WALKER: Schlesinger, too, has shown cyclic waves of virus 

 level and substrate levels in the cells. 



ANDRE WES: Dr. Sulkin, you were quoted by Dr. Metcalf. 

 Have you got any comments to make? 



SULKIN: No, not particularly, because when those experiments 

 were done back in 1941 and 1942, we knew nothing about neura- 

 minidase, inhibitors, and so forth. It was sort of a naive ex- 

 periment. 



ANDREWES: We were all naive in those days. 



SULKIN: The results have been subsequently duplicated by other 

 workers, 



CAMPBELL: Frank Lanni has done quite a bit on this inhibitor. 

 Didn't he come up with a chemical nature of it and do some kinetic 

 studies ? 



METCALF: Lanni studied the interaction between enzymatically 

 active swine influenza and egg white inhibitory mucoprotein. 

 He described the kinetics of inhibitor inactivation, basing his 



1 Larmi, F., and Y. T. Lanni. 1955. Virology 1: 40-57. 



340 



