UV-Vis Spectrophotometry as a Useful Technique to Study the Heme-containing Proteins: Structural and Functional Characteristics ofGamma Irradiated Hemoglobin

UV-Visible spectrophotometry is a general and useful analytical instrument which is found in everychemical and biological laboratory. This simple and low cost apparatus play a key role in quantitativeanalysis, qualification and kinetic study of biological processes. One of the most important classes ofbiological molecules is the heme containing proteins. Hemeproteins have diverse biological functionsincluding oxygen transport, catalysis, electron transfer and biological defense. All these diverse abilitiesare originated from approximately the same prosthetic heme group.The heme group shows somecharacteristic bands at UV-Vis spectra of haemproteins. In this study,the UV-Vis spectroscopy wasapplied to study the structural changeof hemoglobin affected by gamma irradiation. Some functionalbehaviors such as aggregation and oxygen affinity of hemoglobin were studied using UV-Visspectrophotometry. The UV-Vis spectra of hemoglobin could be categorized in some structural andfunctional characteristic regions. The globin band at 280nm is completely structural while the Q band at500-600 nm is exactly a functional peak, and the soret band at 370-450 nm shows both behaviors.Theirradiation dose up to 190 Gy changes just functional part but upper doses affect the structural globin parttoo.Position of the bands, relative intensity of the structural and functional peaks to each other and thepresence or absence of some peaks could predict some structural and functional changes in otherhemoproteins.

کلیدواژه ها:

Hemoprotein ، UV-Vis Spectroscopy ، Gamma Radiation ، Hemoglobin ، Aggregation