o‐Quinone/quinone methide isomerase: A novel enzyme preventing the destruction of self‐matter by phenoloxidase‐generated quinones during immune response in insects

FEBS Letters

Saul, Steven J.¹  Sugumaran, Manickam¹ 

[1] Department of Biology, University of Massachusetts at Boston, Harbor Campus, Boston, MA 02125, USA

关键词: Immunity;    Phenoloxidase;    Melanization;    Quinone tautomerase;    Quinone methide;    (Sarcophaga bullata);    NADA;    N-acetyldopamine;    NANE;    N-acetyl-norepinephrine;   

DOI  :  10.1016/0014-5793(89)80614-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Melanization and encapsulation of invading foreign organisms observed during the immune response in insects is known to be due to the action of activated phenoloxidase. Phenoloxidase-generated quinones are deposited either directly or after self-polymerization on foreign objects accounting for the observed reactions. Since the reactions of quinones are nonenzymatic, they do not discriminate self from nonself and hence will also destroy self-matter. In this report we present evidence for the presence of a novel quinone/quinone methide isomerase in the hemolymph of Sarcophaga bullata which destroys long-lived quinones and hence acts to protect the self-matter. Quinone methides, formed by the action of this enzyme on physiologically important quinones, being unstable undergo rapid hydration to form nontoxic metabolites.

【 授权许可】

Unknown