Lectin that specifically recognizes microbial carbohydrate chains in a calcium-dependent manner (PubMed:11313366, PubMed:26148048). Binds to microbial glycans that contain a terminal acyclic 1,2-diol moiety, including beta-linked D-galactofuranose (beta- Galf), D-phosphoglycerol-modified glycans, D-glycero-D-talo-oct-2- ulosonic acid (KO) and 3-deoxy-D-manno-oct-2-ulosonic acid (KDO) (PubMed:26148048). Binds to glycans from Gram-positive and Gram- negative bacteria, including K.pneumoniae, S.pneumoniae, Y.pestis, P.mirabilis and P.vulgaris (PubMed:26148048). Does not bind human glycans (PubMed:26148048). Probably plays a role in the defense system against microorganisms (Probable). May function as adipokine that has no effect on basal glucose uptake but enhances insulin-stimulated glucose uptake in adipocytes (PubMed:16531507). Increases AKT phosphorylation in the absence and presence of insulin (PubMed:16531507). May interact with lactoferrin/LTF and increase its uptake, and may thereby play a role in iron absorption (PubMed:11747454, PubMed:23921499). {ECO:0000269|PubMed:11313366, ECO:0000269|PubMed:16531507, ECO:0000269|PubMed:23921499, ECO:0000269|PubMed:26148048, ECO:0000305, ECO:0000305|PubMed:11747454}. This is the function of ITLN1 (intelectin 1, ENSG00000179914).