Structural and Functional Characterization of a New Double Variant Haemoglobin (HbG-Philadelphia/Duarte )
Table 1
Oxygen binding properties of purified HbG-Philadelphia/Duarte.
pH
logโp50
p50HbA/p50HbG Philadelphia/Duarte
6.47
0.81 (1.13)
2.56 (2.71)
2.09
โ5โmM 2,3-DPG
7.05
0.67 (0.94)
2.54 (2.67)
1.86
7.4
0.41 (0.66)
2.64 (3.0)
1.77
Alkaline Bohr effect
โ0.43 (โ0.50)
6.54
1.09 (1.47)
2.40 (2.74)
1.40
+5โmM 2,3-DPG
7.18
0.88 (1.30)
2.29 (2.78)
2.63
7.44
0.67 (1.0)
2.45 (2.96)
2.14
Alkaline Bohr effect
โ0.46 (โ0.52)
Corresponding values for HbA are given in parentheses. Data were obtained with 0.1โM Bis-Tris/Tris buffer + 0.1โM NaCl at 25ยฐC. O2 pressure is expressed in Torr units. An average S.D. of 5% for values of logโp50 was calculed.