Involved in the recognition of invading microorganisms activating the phenoloxidase cascade (PubMed:10671539, PubMed:3136171, PubMed:19561300). Binds specifically to beta-1,3-glucan (PubMed:10671539, PubMed:3136171, PubMed:19561300, PubMed:21697086). Binds to both curdlan, a linear water-insoluble beta-1,3-glucan polysaccharide, and laminarin, a water-soluble beta-1,3-glucan polysaccharide containing beta-1,6 branches (PubMed:19561300). Monomer. Hemocytes, fat body and epidermal cells. By bacterial and yeast infection. Glycosylated. Belongs to the insect beta-1,3-glucan binding protein family.