Composition of Salivary Gland Extracts from the Leech Haementeria ghilianii

Abstract

The giant leech, Haementeria ghilianii, originating from French Guyana, has two pairs of salivary glands. From the anterior and posterior glands, approximately 1.5 and 0.3 mg of protein per leech, respectively, have been extracted. Electrophoretic analysis showed that the protein composition of the anterior and posterior gland extracts is completely different. However, both gland extracts contain fibrinolytic activity associated with only one electrophoretic band. The fractionation of salivary gland homogenates by differential ultracentrifugation showed that the fibrinolytic activity is found entirely in the cytosol fraction. 259

Anticoagulants from Hematophagous

“…Antistasin features 119 residues of amino acids with the domain I (residues 1-55) being 56% similar to the domain II (residues . Of the nine residues of the C-terminal (111)(112)(113)(114)(115)(116)(117)(118)(119), domain portion four was positively charged [86], and their active site was located on domain I [88][89][90]. The cDNA of antistasin was cloned [89] and the recombinant protein expressed in system of baculovirus vector in insect cells [90].…”

“…Hementin is responsible for proteolysis of blood fibrinogen with formation of products which block conversion of fibrinogen into fibrin catalyzed by thrombin; this molecule was discovered in salivary gland from Haementeria ghilianii [115]. Since fibrinogen is involved in the formation of platelet clot, hementin is able to prevent the platelet aggregation induced by ADP and collagen; on the other hand, it can also induce disaggregation of platelet aggregation induced by ADP, but not collagen [116].…”

A Protein from the Salivary Glands of the Giant Amazon Leech with High Sequence Homology to a Nicotinic Acetylcholine Receptor Subunit

“…Placing intact salivary glands in a Ca2+-free solution causes the production of copi ous amounts of secretion from the proboscis (W uttke et a l, 1989) but so far it was not possible to correlate the activity of a m em brane protein with secretion. The secretions in the salivary sys tem of H. ghilianii have been shown to consist of complex mixtures of proteins, some with anticoag ulant activity, presumed to have a role in the feed ing mechanism (Budzynski et al, 1981, Sawyer et al, 1991. Although the mechanisms of secretion in the salivary system of this leech have been well studied from an electrophysiology point of view and there has been a volume of work on the bio chemical characterisation of the secretion compo nents, very little is known about the cellular mech anisms underlying the process of secretion.…”

Protease Inhibitors in Haementeria Leech Species

“…At least one of these inhibitors, hirudin (1), serves as anticoagulant in connection with the blood-sucking feeding habit of these animals. Budzynski et al (4,5) have reported the presence of a fibrinogenolytic and fibrinolytic enzyme in salivary gland extract from the South American giant leech Haementeria ghilianii which they called hementin. Inhibitors of thrombin were absent in salivary glands of this leech.…”