Observation of heme transfer from cytochrome b5 to DNA aptamer.
Heme transfer is commonly observed from one heme protein to the other such as from cytochrome b(5) (cyt b(5)) to apo-myoglobin. In this study, instead of to another heme protein, we observed the heme transfer from wild-type (WT) cyt b(5), H39C cyt b(5) with heme axial ligand His39 mutated to Cys39, and DME cyt b(5) with heme replaced by protoporphyrin IX dimethyl ester, to a heme DNA aptamer, PS2.M, respectively, with a different rate constant. The heme transfer was further confirmed by the enhancement of peroxidase activity of the cyt b(5)s-PS2.M system due to the formation of catalytic PS2.M-heme complex. This study provides valuable insights into both cyt b(5)-heme and PS2.M-heme interactions and shows that heme transfer from heme protein to heme-aptamer can be used to evaluate the relative stability of heme proteins. In addition, this study sheds light on the maturation of heme proteins in vivo by interacting with DNA/RNA enzymes.
School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China. linlinying@hotmail.com
Ying-Wu
YW
Lin
Mei-Hui
MH
Sun
Dun
D
Wan
Li-Fu
LF
Liao
D000818:Animals; D052157:Aptamers, Nucleotide / Q000737:chemistry / Q000378:metabolism*; D055162:Biocatalysis; D002417:Cattle; D018360:Crystallography, X-Ray; D015786:Cytochromes b5 / Q000737:chemistry / Q000378:metabolism*; D006139:Guaiacol / Q000737:chemistry; D006418:Heme / Q000737:chemistry / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000737:chemistry; D007700:Kinetics; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000378:metabolism; D011524:Protoporphyrins / Q000737:chemistry / Q000378:metabolism; D013056:Spectrophotometry, Ultraviolet; D013997:Time Factors
D052157:Aptamers, Nucleotide; D011524:Protoporphyrins; D006418:Heme; D006139:Guaiacol; D015786:Cytochromes b5; D006861:Hydrogen Peroxide; D009195:Peroxidase; C041104:dimethyl protoporphyrin IX