Interactions between human hemoglobin subunits and peroxiredoxin 2.

Red blood cells (RBCs) are exposed to exogenous reactive oxygen species in the circulatory system. To this end, the interactions between the different hemoglobin (Hb) subunits and peroxiredoxin 2, which is a ubiquitous member of the antioxidant enzymes that also controls the cytokine-induced peroxide levels, were assessed. We predicted by the increment of diversity with quadratic discriminant analysis (IDQD) that peroxiredoxin2 (Prx2) could interact with the hemoglobin alpha, beta and gamma subunits but not with the delta subunit. Coimmunoprecipitation (co-IP), electrospray ionization quadrupole time of flight (ESI-Q-TOF) mass spectrometry, Western blotting and X-ray absorption fine structure (XAFS) spectroscopy were performed to verify these predictions. The results showed that Prx2 was a member of the beta-globin immunoprecipitating complex that existed in hemoglobin A, hemolysate-hemoglobin A, hemoglobin A-hemoglobin A₂, hemolysate-hemoglobin A-hemoglobin A₂ and hemoglobin A₂ but not in hemolysate-hemoglobin A₂. Adding Prx2 to hemoglobin A altered the second shell of iron embedded in hemoglobin A. Therefore, Prx2 interacts with hemoglobin A (Alpha₂Beta₂) and hemoglobin F (Alpha₂Gamma₂) but not with hemoglobin A₂ (Alpha₂Delta₂).

KEYWORDS: {{ getKeywords(articleDetailText.words) }}