Skip to main content
Log in

The hemolymph coagulation system in invertebrate animals

  • Special Issue: The Fifth Symposium Of The Federation Of Asian And Oceanian Biochemists. “Enzyme Mechanisms” (Part III)
  • Published:
Journal of Protein Chemistry Aims and scope Submit manuscript


A hemocyte lysate from horseshoe crab produced a gel, when exposed to Gram-negative bacterial endotoxins. This gelation reaction of the lysate, so-called Limulus test, has been widely employed as a simple and very sensitive assay method for endotoxins. Recent biochemical studies on the principle of Limulus test indicate that the hemocytes contain several serine protease zymogens, which constitute a coagulation cascade triggered by endotoxins, and that there is a (1 → 3)-β-d-glucan-mediated coagulation pathway which also results in the formation of gel. Up to now, six protein components, designated coagulogen, proclotting enzyme, factor B, factor C, factor G and anti-LPS factor, all of which are closely associated with the endotoxin-mediated coagulation pathway, have been purified and biochemically characterized. Among these components, the complete amino acid sequences of coagulogens isolated from one American and three Asian species of horseshoe crabs have been established. Moreover, the reconstitution experiment using the isolated clotting factors, C, B, proclotting enzyme and coagulogen in the presence of endotoxin, leads to the formation of coagulin get. Based on these results, we propose here a mechanism for the Limulus coagulation cascade.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others


Download references

Author information

Authors and Affiliations


Rights and permissions

Reprints and permissions

About this article

Cite this article

Iwanaga, S., Morita, T., Miyata, T. et al. The hemolymph coagulation system in invertebrate animals. J Protein Chem 5, 255–268 (1986).

Download citation

  • Received:

  • Published:

  • Issue Date:

  • DOI:

Key words