title: A novel analytical method to evaluate directly catalase activity of microorganisms and mammalian cells by ESR oximetry.
abstract: Electron spin resonance (ESR) oximetry technique was applied for analysis of catalase activity in the present study. Catalase activity was evaluated by measuring oxygen from the reaction between hydrogen peroxide (H(2)O(2)) and catalase-positive cells. It was demonstrated that the ESR spectra of spin-label probes, 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPOL), 4-oxo-2,2,6,6-tetramethyl-1-piperidinyloxy (4-oxo-TEMPO) and 4-maleimido-2,2,6,6-tetramethyl-1-piperidinyloxy (4-maleimido-TEMPO) in the presence of H(2)O(2) were broadened with the concentrations of catalase. It was possible to make a calibration curve for catalase activity by peak widths of the spectra of each spin-label probe, which are broadened dependently on catalase concentrations. The broadened ESR spectra were also observed when the catalase-positive micro-organisms or the mammalian cells originally from circulating monocytes/macrophages were mixed with TEMPOL and H(2)O(2). Meanwhile, catalase-negative micro-organisms caused no broadening change of ESR spectra. The present study indicates that it is possible to evaluate directly the catalase activity of various micro-organisms and mammalian cells by using an ESR oximetry technique.
authors.affiliation: New Industry Creation Hatchery Center, Tohoku University, Sendai, Japan. keisuke1@mail.tains.tohoku.ac.jp
authors.forename: Keisuke
authors.initials: K
authors.lastname: Nakamura
authors.forename: Taro
authors.initials: T
authors.lastname: Kanno
authors.forename: Takayuki
authors.initials: T
authors.lastname: Mokudai
authors.forename: Atsuo
authors.initials: A
authors.lastname: Iwasawa
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Niwano
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kohno
mesh_terms: D000818:Animals; D001412:Bacillus subtilis / Q000737:chemistry / Q000378:metabolism; D001419:Bacteria / Q000378:metabolism*; D002138:Calibration; D002374:Catalase / Q000032:analysis / Q000378:metabolism*; D002477:Cells / Q000378:metabolism; D002478:Cells, Cultured; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D003497:Cyclic N-Oxides / Q000737:chemistry / Q000494:pharmacology; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods / Q000592:standards; D004926:Escherichia coli / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008322:Mammals / Q000378:metabolism*; D051379:Mice; D010100:Oxygen / Q000032:analysis*; D013113:Spin Labels; D014216:Triacetoneamine-N-Oxyl / Q000737:chemistry / Q000494:pharmacology
chemical_list: D003497:Cyclic N-Oxides; D013113:Spin Labels; C017480:4-maleimido-2,2,6,6-tetramethylpiperidinooxyl; D014216:Triacetoneamine-N-Oxyl; D002374:Catalase; D010100:Oxygen; C001803:tempol