title: Ozone production by amino acids contributes to killing of bacteria.
abstract: Reactive oxygen species produced by phagocytosing neutrophils are essential for innate host defense against invading microbes. Previous observations revealed that antibody-catalyzed ozone formation by human neutrophils contributed to the killing of bacteria. In this study, we discovered that 4 amino acids themselves were able to catalyze the production of an oxidant with the chemical signature of ozone from singlet oxygen in the water-oxidation pathway, at comparable level to antibodies. The resultant oxidant with the chemical signature of ozone exhibited significant bactericidal activity in our distinct cell-free system and in human neutrophils. The results also suggest that an oxidant with the chemical signature of ozone produced by neutrophils might potentiate a host defense system, when the host is challenged by high doses of infectious agents. Our findings provide biological insights into the killing of bacteria by neutrophils.
authors.affiliation: Departments of Hematology and Oncology and Anesthesia, Kyoto University Hospital, Kyoto 606-8507, Japan.
authors.forename: Kouhei
authors.initials: K
authors.lastname: Yamashita
authors.forename: Takashi
authors.initials: T
authors.lastname: Miyoshi
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Arai
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Endo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Itoh
authors.forename: Keisuke
authors.initials: K
authors.lastname: Makino
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Mizugishi
authors.forename: Takashi
authors.initials: T
authors.lastname: Uchiyama
authors.forename: Masataka
authors.initials: M
authors.lastname: Sasada
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000737:chemistry / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000378:metabolism*; D002384:Catalysis; D004926:Escherichia coli / Q000378:metabolism; D006105:Granulomatous Disease, Chronic / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D008297:Male; D009504:Neutrophils / Q000378:metabolism*; D016877:Oxidants / Q000096:biosynthesis; D010084:Oxidation-Reduction; D010126:Ozone / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D026082:Singlet Oxygen / Q000378:metabolism
chemical_list: D000596:Amino Acids; D000900:Anti-Bacterial Agents; D016877:Oxidants; D017382:Reactive Oxygen Species; D026082:Singlet Oxygen; D010126:Ozone; D006861:Hydrogen Peroxide