Method for assaying activity of prophenoloxidase activating enzyme and application thereof

摘要

A method for assaying an activity of a prophenoloxidase activating enzyme (PPAE), comprising assaying at least X-Arg or Y produced upon contact of the PPAE with a peptide chain of the formulaX-Arg-Ywherein X is an optionally labeled amino acid residue or peptide residue, having an optionally protected alpha -amino group or N-terminal, provided that the amino acid residue adjoining Arg is not Gly or Ala, and Y is an organic residue capable of binding to a carboxyl group of Arg by acid amide bonding or ester bonding, or an optionally labeled amino acid residue or peptide residue, having an optionally protected alpha -carboxyl group or C-terminal, the peptide chain capable of being hydrolyzed into X-Arg and Y by a PPAE derived from an insect. According to the present invention, PPAE activity can be quantitatively assayed with precision and a highly precise method for determining beta -1,3-glucan and/or peptidoglycan, wherein said PPAE activity is used as an index, can be provided. In addition, the present invention enables detection of fungi and bacteria without multiplication by culture, which makes early diagnosis of microbial infections possible. The present invention is applicable to a wide range of use such as tests for microbial contamination of water and food, safety tests of therapeutic agents such as antibiotics and injectable preparations, etc.