Maggot chymotrypsin I from Lucilia sericata is resistant to endogenous wound protease inhibitors

Br J Dermatol. 2011 Jan;164(1):192-6. doi: 10.1111/j.1365-2133.2010.10081.x. Epub 2010 Nov 29.


Background: A chymotrypsin found in the secretions of Lucilia sericata and manufactured as a recombinant enzyme degrades chronic wound eschar ex vivo.

Objectives: To characterize the inhibition profile of the L. sericata recombinant chymotrypsin I.

Methods: Activity of recombinant chymotrypsin I and its sensitivity to endogenous inhibitors were determined enzymatically using the fluorogenic substrate succinyl-alanyl-alanyl-prolyl-phenylalanyl-aminomethyl coumarin.

Results: We report the presence of high concentrations of two endogenous inhibitors, α1-antichymotrypsin and α1-antitrypsin, in wound eschar and a trace of a third, α2-macroglobulin, with the potential to inhibit this debridement process. However, the addition of a soluble and inhibitor-containing extract of chronic wound eschar to chymotrypsin I did not affect activity of the enzyme, neither did the addition of purified native α1-antichymotrypsin or α1-antitrypsin, although chymotrypsin I was inhibited by α2-macroglobulin. Conversely, the mammalian equivalent, α-chymotrypsin, was inhibited by the purified native α1-antichymotrypsin, α1-antitrypsin and α2-macroglobulin and by the soluble extract of wound eschar.

Conclusions: The data suggest that the maggot-derived chymotrypsin I is biochemically distinct from human α-chymotrypsin and the lack of inhibition by wound eschar suggests a means by which chymotrypsin I activity survives within the wound to contribute towards debridement during maggot biotherapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aprotinin / pharmacology
  • Blotting, Western
  • Chymotrypsin / antagonists & inhibitors*
  • Chymotrypsin / metabolism
  • Diptera / enzymology*
  • Electrophoresis, Gel, Two-Dimensional / methods
  • Humans
  • Larva / enzymology
  • Skin / enzymology*
  • Trypsin Inhibitors / pharmacology*
  • Wound Healing / physiology
  • Wounds and Injuries / enzymology*
  • Wounds and Injuries / therapy


  • Trypsin Inhibitors
  • Aprotinin
  • Chymotrypsin