Development of catalase activity in yeast in relation to growth and respiration

1. 1) When yeast cells grown anaerobically were adapted to aerobicculture in a normal medium, catalase formation was markedlyenhanced after the earlier stage of exponential growth of thecells. The same thing occurred with cells transferred from ananaerobic culture into a nitrogen deficient medium.
2. 2) Thecatalase activity of aerobically grown cells declinedprogressivelyuntil glucose, which had been added to the mediumwas profoundlyexhausted. This decline was followed by a progressiverecoveryof activity to a normal level with the growth of thecells.Similar behavior of catalase was also seen at low concentrationsof glucose, except that an abrupt rise in activity was observedat the beginning of incubation. Even when cells which had declinedto a minimum of catalase activity were aerated in phosphatebuffer, they continued to synthesize catalase.
3. 3) The patternof alteration of catalase activity during cellgrowth was accompaniedby a comparable pattern of alterationin respiratory capacity.On the basis of this finding, togetherwith the fact that antimycinA causes intensive depression incatalase formation, it maybe inferred that the formation ofthe respiratory chain conductsthe formation of catalase.
4. 4) In the presence of ethyl alcoholas the carbon source inplace of glucose, a rise in both catalaseactivity and respiratorycapacity occurred from initiation ofincubation. This fact canbe interpreted to mean that the repressiveeffect of glucoseon catalase formation depends on the aerobiccharacter of thecells.

(Received February 26, 1968; )