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

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 LC 50 of 850.1 μg/mL, whereas HGL showed LC 50 of 9.5 µg/mL.

Purification and erythrocyte-membrane perturbing activity of a ketose-specific lectin from Moringa oleifera seeds

“…3 a) . Obtained result was similar to the report on Holothuria grisea lectin (HGL) [59] , cMoL [24] , and Sterculia foetida hemolytic lectin [49] . Hemagglutinating activity of MoL was stable within pH 2–4, however, above pH 4, the activity decreased rapidly and was lost at pH 11 ( Fig.…”

MytiLec-1 Shows Glycan-Dependent Toxicity against Brine Shrimp Artemia and Induces Apoptotic Death of Ehrlich Ascites Carcinoma Cells In Vivo

“…MytiLec-1 showed mild lethality with an LC 50 value of 384.53 μg/mL (Figure 2). In a previous study, CvL-2, another galactose-binding trimeric lectin from Cliona varians , was reported to have lower lethality (LC 50 value of 850.1 μg/mL) since the Sea cucumber ( Holothuria grisea ) lectin HGL was highly toxic (LC 50 value of 9.5 μg/mL) against Artemia nauplii [21]. Two other lectins, H-1 and H-2, from a marine sponge Haliclona caerulea , showed higher toxicity (LC 50 value of 6.4 and 142.1 μg/mL, respectively) than MytiLec-1, putting it in a category of mildly toxic lectins [22].…”

Antiproliferative and Antimicrobial Potentials of a Lectin from Aplysia kurodai (Sea Hare) Eggs

“…Despite having much lower LC 50 value (384.53 µg/mL), MytiLec-1, a lectin from another marine mussel, could kill Burkitt lymphoma and U937 cells in vitro, as well as Ehrlich ascites carcinoma cells in vivo [ 3 , 29 ]. A variable level of toxicity with different LC 50 values (850.1, 142.1, 9.5, and 6.4 μg/mL) was also observed in lectins purified from marine sponges and a sea cucumber [ 30 , 31 ].…”

“…U937 is a monocytic human myeloid leukemia cell line frequently used in biomedical research [ 40 ]. Compared to AKL-40, MytiLec-1 and Ricin inhibited growth of these cells in vitro at much lower concentrations, which also indicates the difference of glycan recognition for these three lectins [ 30 , 41 , 42 ].…”