Lectins and glucanases exhibit the common property of reversibly binding to specific complex carbohydrates. The lectins/glucanases are a diverse group of proteins found in a wide range of species from prokaryotes to humans. The different family members all contain a concanavalin A-like domain, which consists of a sandwich of 12-14 beta strands in two sheets with a complex topology. Members of this family are diverse, and include the lectins: legume lectins, cereal lectins, viral lectins, and animal lectins. Plant lectins function in the storage and transport of carbohydrates in seeds, the binding of nitrogen-fixing bacteria to root hairs, the inhibition of fungal growth or insect feeding, and in hormonally regulated plant growth . Protein members include concanavalin A (Con A), favin, isolectin I, lectin IV, soybean agglutinin and lentil lectin. Animal lectins include the galectins, which are S-type lactose-binding and IgE-binding proteins such as S-lectin, CLC protein, galectin1, galectin2, galectin3 CRD, and Congerin I .
Other members with a Con A-like domain include the glucanases and xylanases. Bacterial and fungal beta-glucanases, such as Bacillus 1-3,1-4-beta-glucanse, carry out the acid catalysis of beta-glucans found in microorganisms and plants . Similarly, kappa-Carrageenase degrades kappa-carrageenans from marine red algae cell walls . Xylanase and cellobiohydrolase I degrade hemicellulose and cellulose, respectively [9618460, 9466911].
There are many Con A-like domains found in proteins involved in cell recognition and adhesion. For example, several viral and bacterial toxins carry Con A-like domains. Examples include the Clostridium neurotoxins responsible for the neuroparalytic effects of botulism and tetanus . The Pseudomonas exotoxin A, a virulence factor which is highly toxic to eukaryotic cells, causing the arrest of protein synthesis, contains a Con A-like domain involved in receptor binding . Cholerae neuraminidase can bind to cell surfaces, possibly through their Con A-like domains, where they function as part of a mucinase complex to degrade the mucin layer of the gastrointestinal tract . The rotaviral outer capsid protein, VP4, has a Con A-like sialic acid binding domain, which functions in cell attachment and membrane penetration .
Con A-like domains also play a role in cell recognition in eukaryotes. Proteins containing a Con A-like domain include the sex hormone-binding globulins which transport sex steroids in blood and regulate their access to target tissues , laminins which are large heterotrimeric glycoproteins involved in basement membrane architecture and function , neurexins which are expressed in hundreds of isoforms on the neuronal cell surface, where they may function as cell recognition molecules  and sialidases that are found in both microorganisms and animals, and function in cell adhesion and signal transduction .
Other proteins containing a Con A-like domain include pentraxins and calnexins. The pentraxin PTX3 is a TNFalpha-induced, secreted protein of adipose cells produced during inflammation . The calnexin family of molecular chaperones is conserved among plants, fungi, and animals. Family members include Calnexin, a type-I integral membrane protein in the endoplasmic reticulum which coordinates the processing of newly synthesized N-linked glycoproteins with their productive folding, calmegin, a type-I membrane protein expressed mainly in the spermatids of the testis, and calreticulin, a soluble ER lumenal paralog .