To clarify the enzymatic properties of catalase from the acatalasemic mice, the change in the enzymatic activity during maturation of reticulocytes was observed both in normal and anemic conditions. Catalase activity in the blood of acatalasemic mice retained its maximum level 5 days after final injection of phenylhydrazine. An intimate lag correlation coefficient was obtained between reticulocyte count and catalase activity in blood by one day shift in acatalasemic mice and three days shift in normal mice, which corresponded to the interval between maximum peaks of reticulocyte count and catalase activity.
The erythrocytes and reticulocytes were also counted, and the catalase activity per erythrocyte and reticulocyte in the blood of normal and acatalasemic mice was calculated. The catalase activity in blood due to reticulocyte retained its maximum level 5 days after injection of phenylhydrazine in normal and acatalasemic mice. The results revealed that catalase activity in acatalasemic mice was very low in reticulocyte and yet its degeneration by maturation was considerably great. Catalase activity per reticulocyte in the blood of acatalasemic mice was 55% of that of normal mice. Degeneration ratio expressed as (catalase activity in reticulocytes-that in erythrocytes)/catalase activity in reticulocytes was 88% in acatalasemic mice and 34% in normal mice. The difference in catalase activity between reticulocytes and erythrocytes in the blood of acatalasemic mice was also higher than that of normal mice. Thus the catalase activity in erythrocytes in the blood of acatalasemic mice was 10% of that of normal mice.