Prophenoloxidase b hexamer, Marsupenaeus japonicus.
Prophenoloxidase (proPO ) is a modified form of the complement response found in some invertebrates, including insects , crabs and worms .[ 1] It is a copper -containing metalloprotein .[ 2]
A major innate defense system in invertebrates is the melanization of pathogens and damaged tissues. This important process is controlled by the enzyme phenoloxidase (PO).[ 3] The conversion of prophenoloxidase to the active form of the enzyme can be brought about by minuscule amounts of molecules such as lipopolysaccharide , peptidoglycan and beta-1,3-glucans from microorganisms .[ 4]
However, it still has many arguments in the innate immune function, especially in model invertebrate animal.[ 5] The proPO homologous-protein in mammal also does not have any immune activity. Thus, it might be difficult to conclude its function in immunity.
^ Beck, Gregory; Habicht, Gail S. (November 1996). "Immunity and the Invertebrates" (PDF) . Scientific American . 275 (5): 60–66. Bibcode :1996SciAm.275e..60B . doi :10.1038/scientificamerican1196-60 . PMID 8875808 .
^ Sánchez-Aparicio, José-Emilio; Tiessler-Sala, Laura; Velasco-Carneros, Lorea; Roldán-Martín, Lorena; Sciortino, Giuseppe; Maréchal, Jean-Didier (2021-01-25). "BioMetAll: Identifying Metal-Binding Sites in Proteins from Backbone Preorganization" . Journal of Chemical Information and Modeling . 61 (1): 311–323. doi :10.1021/acs.jcim.0c00827 . hdl :10261/310255 . ISSN 1549-9596 . PMID 33337144 .
^ Cerenius, L; Söderhäll, K (2004). "The prophenoloxidase-activating system in invertebrates". Immunological Reviews . 198 : 116–26. doi :10.1111/j.0105-2896.2004.00116.x . PMID 15199959 . S2CID 10614298 .
^ Söderhäll, K; Cerenius, L (1998). "Role of the prophenoloxidase-activating system in invertebrate immunity". Current Opinion in Immunology . 10 (1): 23–8. doi :10.1016/S0952-7915(98)80026-5 . PMID 9523106 .
^ Leclerc, V; Reichhart, JM (2006). "Prophenoloxidase activation is not required for survival to microbial infections in Drosophila" . EMBO Rep . 7 (2): 231–5. doi :10.1038/sj.embor.7400592 . PMC 1369246 . PMID 16322759 .