{'fraction_non_alphanumeric': 0.028363047001620744, 'fraction_numerical': 0.013776337115072933, 'mean_word_length': 4.563063063063063, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
HEXOKINASE IN ERYTHROCYTES OF NEWBORN INFANTS AND ADULTS: ISOLATION AND CHARACTERIZATION OF THE ISOENZYMES

The metabolism of erythrocytes of newborn infants (nRBC) is different from that of adult erythrocytes (aRBC). Since hexokinase plays an important role in the regulation of glycolysis we investigated the distribution and properties of the hexokinase isoenzymes (Hxi) in nRBC and aRBC.By column chromatography with DEAE-Glycophase we isolated two Hxi in aRBC. Hxi I represented more than 90% of the total hexokinase activity in aRBC. In nRBC we found only one Hxi which was eluted with a slightly higher conductivity than Hxi I from aRBC.Km values for glucose and ATP, inhibition by ADP, pH optimum and thermostability of aRBC Hxi were identical to rat liver Hxi I and III. The Hxi from nRBC, however, is different from all rat liver and aRBC Hxi. It shows a higher Km values for glucose and ATP (0.1 mM and 1.8 mM respectively) than Hxi I from aRBC (0.047 mM and 0.98 mM respectively). 2,3-DPG inhibited the Hxi from nRBC more than Hxi I from aRBC.The low affinity for glucose and the increased inhibition 2,3-DPG of the nRBC Hxi may explain the decreased glycolytic rate compared with aRBC of similar age distribution of nRBC.