Catalase Biosynthesis in Yeast: Formation of Catalase A and Catalase T during Oxygen Adaptation of <i>Saccharomyces cerevisiae</i>

Abstract

Catalase A from Saccharomyces cerevisiae and its biosynthetic precursors can specifically be immunoprecipitated from extracts obtained from yeast cells grown in the presence of l ‐[ 3 H]leucine or 59 FeCl 3 . The enzyme and its precursors recognized by a specific antiserum are absent from anaerobic cells. During oxygen adaptation of yeast pre‐grown on 0.3% glucose under anaerobic conditions catalase A is formed via a heme‐less precursor, probably the apomonomer of the protein, and a heme‐containing intermediate. When cells are grown in the presence of Tween 80 the amount of catalase A, but not of catalase T, increases 4‐fold. Comparison of the mode of synthesis of catalase T and A shows that no precursor‐product relationship exists between the two proteins.