Characterization of a defense complex consisting of interleukin 1 and phenol oxidase from the hemolymph of the tobacco hornworm, Manduca sexta.
Hemolymph of fifth instar Manduca sexta larvae collected under non-sterile conditions exhibited the presence of a novel high molecular weight protein complex, which was absent from the hemolymph collected aseptically. The high molecular weight complex consisted of, at least prophenol oxidase, phenol oxidase, and an interleukin 1-like molecule, thereby demonstrating the generation of this complex as a consequence of a host defense response. While the native phenol oxidase and the interleukin 1-like molecule possessed molecular weights of about 80,000 and 17,000, respectively, the complex had a molecular weight of about 400,000. Apart from prophenol oxidase, phenol oxidase, and interleukin 1, dopachrome isomerase and other, as of yet unidentified, proteins may be part of the complex as judged by the presence of additional bands observed during SDS-polyacrylamide gel electrophoresis. The significance of the assembly of this defense complex for insect host defense strategies is discussed.
Beck
G
G
Department of Biology, University of Massachusetts, Boston 02125-3393, USA.
Cardinale
S
S
Wang
L
L
Reiner
M
M
Sugumaran
M
M
D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D006458:Hemolymph / Q000276:immunology*; D007106:Immune Sera; D007375:Interleukin-1 / Q000302:isolation & purification / Q000378:metabolism*; D019746:Intramolecular Oxidoreductases; D007535:Isomerases / Q000302:isolation & purification; D007814:Larva; D018402:Manduca / Q000276:immunology*; D008970:Molecular Weight; D014442:Monophenol Monooxygenase / Q000302:isolation & purification / Q000378:metabolism*; D011817:Rabbits
D007106:Immune Sera; D007375:Interleukin-1; D014442:Monophenol Monooxygenase; D007535:Isomerases; D019746:Intramolecular Oxidoreductases; C042501:dopachrome isomerase