Ozone production by amino acids contributes to killing of bacteria.
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.
Yamashita
Kouhei
K
Departments of Hematology and Oncology and Anesthesia, Kyoto University Hospital, Kyoto 606-8507, Japan.
Miyoshi
Takashi
T
Arai
Toshiyuki
T
Endo
Nobuyuki
N
Itoh
Hiroshi
H
Makino
Keisuke
K
Mizugishi
Kiyomi
K
Uchiyama
Takashi
T
Sasada
Masataka
M
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
D000596:Amino Acids; D000900:Anti-Bacterial Agents; D016877:Oxidants; D017382:Reactive Oxygen Species; D026082:Singlet Oxygen; D010126:Ozone; D006861:Hydrogen Peroxide