title: Respiratory protein-generated reactive oxygen species as an antimicrobial strategy.
abstract: The evolution of the host-pathogen relationship comprises a series of invasive-defensive tactics elicited by both participants. The stereotype is that the antimicrobial immune response requires multistep processes. Little is known about the primordial immunosurveillance system, which probably has components that directly link sensors and effectors. Here we found that the respiratory proteins of both the horseshoe crab and human were directly activated by microbial proteases and were enhanced by pathogen-associated molecular patterns, resulting in the production of more reactive oxygen species. Hemolytic virulent pathogens, which produce proteases as invasive factors, are more susceptible to this killing mechanism. This 'shortcut' antimicrobial strategy represents a fundamental and universal mode of immunosurveillance, which has been in existence since before the split of protostomes and deuterostomes and still persists today.
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore 117543.
authors.forename: Naxin
authors.initials: N
authors.lastname: Jiang
authors.forename: Nguan Soon
authors.initials: NS
authors.lastname: Tan
authors.forename: Bow
authors.initials: B
authors.lastname: Ho
authors.forename: Jeak Ling
authors.initials: JL
authors.lastname: Ding
mesh_terms: D000818:Animals; D001770:Blood Bactericidal Activity; D004789:Enzyme Activation; D004792:Enzyme Precursors / Q000378:metabolism; D006433:Hemocyanins / Q000502:physiology*; D006454:Hemoglobins / Q000502:physiology*; D006737:Horseshoe Crabs; D006801:Humans; D007113:Immunity, Innate; D014442:Monophenol Monooxygenase / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D004792:Enzyme Precursors; D006454:Hemoglobins; D017382:Reactive Oxygen Species; D006433:Hemocyanins; D014442:Monophenol Monooxygenase