Hemagglutinating/Hemolytic activities in extracts of marine invertebrates from the Brazilian coast and isolation of two lectins from the marine sponge Cliona varians and the sea cucumber Holothuria grisea.

Plínio Delatorre,Rômulo F Carneiro,Arthur A Melo,Raniere M Moura,Alexandre H Sampaio,Benildo S Cavada,Celso S Nagano,Kyria S Nascimento,Cícera R.F Rodrigues,Silvana Saker-Sampaio

doi:10.1590/0001-3765201520140399

Abstract

Twenty species of marine invertebrates from the Brazilian coast were screened for hemagglutinating/hemolytic activity. In at least twelve tested species, hemagglutinating activity was different for different blood types, suggesting the presence of lectins. Extracts from four species showed hemolytic activity. Two new lectins were purified from the marine sponge Cliona varians (CvL-2) and sea cucumber Holothuria grisea (HGL). CvL-2 was able to agglutinate rabbit erythrocytes and was inhibited by galactosides. The hemagglutinating activity was optimal in pH neutral and temperatures below 70 °C. CvL-2 is a trimeric protein with subunits of 175 kDa. On the other hand, HGL showed both hemagglutinating and hemolytic activity in human and rabbit erythrocytes, but hemolysis could be inhibited by osmotic protection, and agglutination was inhibited by mucin. HGL was stable in pH values ranging from 4 to 10 and temperatures up to 90 °C. In electrophoresis and gel filtration, HGL was a monomeric protein with 15 kDa. CvL-2 and HGL showed different levels of toxicity to Artemia naplii. CvL-2 showed LC50 of 850.1 μg/mL, whereas HGL showed LC50 of 9.5 µg/mL.

Highlights

Marine biodiversity is the result of a long evolutionary history and extreme environmental conditions of pressure, light, oxygen, and temperature, giving rise to organisms with unique features (Ritchie et al 2013)
In at least twelve tested species, hemagglutinating activity was different for different blood types, suggesting the presence of lectin-like molecules in these species; namely, hemagglutinating activity was observed in 60% of the tested species
Similar to lectins isolated from Haliclona caerulea (Carneiro et al 2013), Axinella corrugata (Dresch et al 2011) and Aplysia kurodai (Kawsar et al 2010), HGL showed a high level of cytotoxicity against Artemia nauplii

Summary

Introduction

Marine biodiversity is the result of a long evolutionary history and extreme environmental conditions of pressure, light, oxygen, and temperature, giving rise to organisms with unique features (Ritchie et al 2013). Marine life is much older than earthly life and has been evolving and diversifying longer (Burgess 2012) This amazing, but understudied, species diversity has provided a huge variety of molecules with biotechnological applications. Many of these compounds, which have already been isolated and studied, belong to marine invertebrates, such as sponges, cnidarians, mollusks, arthropods, echinoderms and tunicates (Rasjasa et al 2011). Among these compounds are proteins (Pajic et al 2002, Yoshida et al 2007) and secondary metabolites (Kuramoto et al 2004, Sipkema et al 2005) with a wide range of biological activities. Lectins from marine organisms are one of the promising candidates for useful therapeutic agents because carbohydrate structures, such as proteoglycans, glycoproteins, and glycolipids, have been implicated in certain cell types, and their physiological and pathological functions include host-pathogen interactions and cell-cell communication (Ogawa et al 2011)

Methods

Results

Conclusion