Characterization of the heme iron in pyridoxylated hemoglobin cross-linked by glutaraldehyde using Mössbauer spectroscopy.
The heme iron in human adult hemoglobin modified by both pyridoxal-5'-phosphate and glutaraldehyde was characterized by Mössbauer spectroscopy and compared with non-modified hemoglobin. Mössbauer spectra of the samples were measured at 87 and 295 K (1yophilized form) and at 87 K (frozen solution). The values of quadrupole splitting for the oxy-form of modified hemoglobin were found to be lower than those of the oxy-form of hemoglobin without modifications in lyophilized form and frozen solution, respectively. On the other hand, the values of quadrupole splitting for the deoxy-form of modified and non-modified hemoglobins in frozen solution were the same. The Mössbauer spectra of the oxy-form of modified hemoglobin were also analyzed in terms of the heme iron non-equivalence in alpha- and beta-subunits of tetramer. The differences of the tendencies of temperature dependencies of quadrupole splitting for the oxy-form of modified and non-modified hemoglobins in lyophilized form were shown. These results indicated that the heme iron electronic structure and stereochemistry were changed in the oxy-form of pyridoxylated hemoglobin cross-linked by glutaraldehyde.
Oshtrakh
M I
MI
Division of Applied Biophysics, Faculty of Physical Techniques and Devices for Quality Control, Ural State Technical University, 620002, Ekaterinburg, Russia. oshtrakh@soek.erl.e-burg.ru
Milder
O B
OB
Semionkin
V A
VA
Berkovsky
A L
AL
Azhigirova
M A
MA
Vyazova
E P
EP
D000328:Adult; D003432:Cross-Linking Reagents; D004563:Electrochemistry; D005976:Glutaral; D006418:Heme / Q000737:chemistry*; D006454:Hemoglobins / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D007501:Iron / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D010108:Oxyhemoglobins / Q000737:chemistry; D011732:Pyridoxal Phosphate; D015204:Spectroscopy, Mossbauer; D013237:Stereoisomerism
D003432:Cross-Linking Reagents; D006454:Hemoglobins; D010108:Oxyhemoglobins; D006418:Heme; D011732:Pyridoxal Phosphate; C100003:deoxyhemoglobin; D007501:Iron; D010100:Oxygen; D005976:Glutaral