Oxygenation of hemoglobin

Oxygenation of Hemoglobin Triggers Conformational Changes in the Apoprotein... 

Oxygenation of Hemoglobin Is Accompanied by Large Conformational Changes... 

Fig. 45. Effect of oxygenation of Hemoglobin M -B(B2A6,w-0h)on one of the histidine i4N-EN-DOR lines (Washed whole cells). (Adapted from Ref. 243)...

Upon oxygenation of hemoglobin, two of the heme groups move about 100 pm towards each other while two others separate by about 700 pm Perhaps a better way of describing the movement is to say that one aP half of the molecule rotates 15° relative to the other half.30 These movements are the result of a change in the quaternary structure of the hemoglobin and are responsible for the cooperative effects observed. The quaternary structure exhibited by the deoxy form is called the T state. 

Binding Constants of Protons to Dianions of Dicarboxylic Acids Thermodynamic Functions for Oxygenation of Hemoglobin A Few Well-Known Structural Domains... 

Figure 7-25 (A) Structural changes occurring upon oxygenation of hemoglobin. After Dickerson144 and Perutz.143 (B) "Rotation at the contact ot, p2 causes a jump in the dovetailing of the CD region of a relative to the FG region of 3 and a switch of hydrogen bonds as shown".143 (C) Some details of the salt bridges.

The 02 molecule and its two reduced species 02 and 02 can act as ligands to transition metals. Molecular oxygen reacts reversibly with some metal complexes60 and such reversible reactions are involved in the oxygenation of hemoglobin and myoglobin (Section 17-E-10). 

Benesch RE, Benesch R, Yu CL The oxygenation of hemoglobin in the presence of 2,3-diphosphoglycer-ate. Effect of temperature, pH, ionic strength, and hemoglobin concentration. Biochemistry 1969 8 2567-71. 

Schematic representation of the transfer of CO2 from the alveolus (and its loss in the expired air in the lungs) and oxygenation of hemoglobin. Note that the sequence of events occurring in the pulmonary capillaries is the opposite of the process taking place in the tissue capillaries (Figure 1-5). Solid lines indicate major pathways and broken lines indicate minor pathways. Hb = hemoglobin.

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