title: Polyethylene glycol-modified hemin having peroxidase activity in organic solvents.
abstract: Hemin, having two carboxyl groups, was coupled with monomethoxypolyethylene glycol, PEG, through the ester bond formed with carbodiimide. The PEG-modified hemin was readily soluble not only in neutral aqueous solution but also in organic solvents. Its absorption spectrum in 1,1,1-trichloroethane showed a sharp Soret band at 398 nm. The modified hemin catalyzed the peroxidase-reaction in organic solvent and in aqueous solution using hydrogen peroxide or peroxidized linolenic acid as hydrogen acceptor and o-phenylene diamine as hydrogen donor. The activity of PEG-hemin in 1,1,1-trichloroethane was greater than that in an aqueous solution; k1 values in 1,1,1-trichloroethane were 2.3 X 10(3) M-1 sec-1 with hydrogen peroxide and 7.0 X 10(2) M-1 sec-1 with peroxidized linolenic acid, and the value in an aqueous solution was 3.0 X 10 M-1 sec-1 with hydrogen peroxide.
mesh_terms: D006418:Heme / Q000031:analogs & derivatives*; D006427:Hemin / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism; D008042:Linolenic Acids / Q000494:pharmacology; D010544:Peroxidases / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000494:pharmacology*; D012995:Solubility; D012997:Solvents; D013053:Spectrophotometry; D014240:Trichloroethanes / Q000494:pharmacology; D017962:alpha-Linolenic Acid
chemical_list: D008042:Linolenic Acids; D012997:Solvents; D014240:Trichloroethanes; D017962:alpha-Linolenic Acid; C024566:1,1,1-trichloroethane; D011092:Polyethylene Glycols; D006418:Heme; D006427:Hemin; D006861:Hydrogen Peroxide; D010544:Peroxidases