Different susceptibilities to intracellular proteases of hemoglobin and hemoglobin-haptoglobin complex
Kimura, H.; Yamato, S.; Murachi, T.
Physiological Chemistry and Physics 8(2): 101-106
1976
ISSN/ISBN: 0031-9325 PMID: 10591 Document Number: 99288
The susceptibilities of hemoglobin and hemoglobin-haptoglobin complex to intracellular proteases differ significantly. Hemoglobin and hemoglobin-haptoglobin complex are degested in the regions of pH 5.5-2.5 and 4.0-2.5 respectively, having pH optima at pH 4.0 and 3.0 respectively, by intracellular proteases from rat and mouse liver or spleen. The difference in proteolytic susceptibility is found to be due to the different stabilities to acid among hemoglobin derivatives as evidenced by the measurements of their helical contents in acidic pH.