A cysteine-rich serine protease inhibitor (Guamerin II) from the non-blood sucking leech Whitmania edentula: biochemical characterization and amino acid sequence analysis

A cysteine-rich serine protease inhibitor (Guamerin II) was isolated from the non-blood sucking leech Whitmania edentula. The new inhibitor was identified as a low molecular weight (6,012 Da) polypeptide with some sequence similarities to antistasin, hirustasin and guamerin. The inhibitor contained 56 amino acid residues with 76.8% sequence similarity to guamerin, 48.2% to hirustasin and 28.6% to the first domain of antistasin. This new inhibitor was the first completely sequenced serine protease inhibitor from a non-blood sucking leech. Analysis of the inhibitor revealed that it was active against neutrophil elastase and chymotrypsin, but had no activity against a variety of other proteases. The P1 reactive site residue was identified as methionine and the residues surrounding the P1 site were hydrophobic amino acids. The primary structure of the inhibitor showed no similarity to well-known elastase inhibitors from leeches such as eglin.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Guamerin II, a 6,012 Da, 56-residue cysteine-rich inhibitor isolated from the non-blood-sucking leech Whitmania edentula, is the first fully sequenced serine protease inhibitor from such a leech and inhibits neutrophil elastase and chymotrypsin.

Explore how this research connects to clinical practice

More peer-reviewed studies in Salivary Pharmacology.

• Medicinal leeches and hirudotherapy — Gödekmerdan A et al. (2011)
• PEROXIDATION OF SALIVA LIPIDS IN PATIENTS WITH POSTCOVID SYNDROME DURING HIRUDOTHERAPY — Serikbayeva S et al. (2024)
• Medicinal leech therapy in pain syndromes: a narrative review — Koeppen D, Aurich M, Rampp T (2014)
• Immunomodulatory effects of medicinal leech saliva extract on in vitro activated macrophages — Ayhan H et al. (2024)
• Proteinase inhibitors from the medicinal leech Hirudo medicinalis — Baskova I, Zavalova L (2001)
• Polyfunctionality of destabilase, a lysozyme from a medicinal leech — Baskova I, Zavalova L (2008)
• Make it double: identification and characterization of a Tandem-Hirudin from the Asian medicinal leech Hirudinaria manillensis — Lukas P et al. (2022)
• Use of the medicinal leech in the treatment of ear diseases — Seleznev K et al. (1992)
• Recombinant Destabilase from Hirudo medicinalis Is Able to Dissolve Human Blood Clots In Vitro — Bobrovsky P et al. (2021)
• Effects of Carbon Nanotube Environmental Dispersion on an Aquatic Invertebrate, Hirudo medicinalis — Girardello R et al. (2015)

Browse all ASH-analysed research →