Mushroom lectins: Current status and future perspectives

Abstract

Lectins are nonimmune proteins or glycoproteins that bind specifically to cell surface carbohydrates, culminating in cell agglutination. These are known to play key roles in host defense system and also in metastasis. Many new sources have been explored for the occurrence of lectins during the last few years. Numerous novel lectins with unique specificities and exploitable properties have been discovered. Mushrooms have attracted a number of researchers in food and pharmaceuticals. Many species have long been used in traditional Chinese medicines or functional foods in Japan and other Asian countries. A number of bioactive constituents have been isolated from mushrooms including polysaccharides, polysaccharopeptides, polysaccharide-protein complexes, proteases, ribonucleases, ribosome inactivating proteins, antifungal proteins, immunomodulatory proteins, enzymes, lectins, etc. Mushroom lectins are endowed with mitogenic, antiproliferative, antitumor, antiviral, and immune stimulating potential. In this review, an attempt has been made to collate the information on mushroom lectins, their blood group and sugar specificities, with an emphasis on their biomedical potential and future perspectives.

New lectins from aspergilli and their carbohydrate specificity

“…Mushroom lectins are endowed with antiproliferative, antitumor, mitogenic, hypotensive, vasorelaxing, haemolytic, anti-HIV1 reverse transcriptase and immunepotentiating activities (Singh et al 2010a). They have also been studied for biochemical reagents with valuable carbohydrate binding specificity (Horibe et al 2010).…”

Purification and characterization of a novel anti-HSV-2 protein with antiproliferative and peroxidase activities from <italic>Stellaria media</italic>

“…Examples of this group include trichosanthin (TCS) which is isolated from Trichosanthes kirilowii and inhibits replication of HIV-1 [34], and MAP30 from the seeds of Momordica charantia, which exhibits potent anti-HSV and anti-HIV activities [35]. Lectins are defined by their ability of clumping erythrocytes and other types of animal and human cells [36]. Typhonium divaricatum lectin (TDL) is isolated from Typhonium divaricatum [37] and Polygonatum odoratum lectin (POL) from rhizomes of Polygonatum odoratum [11], both of which have antiviral activity against HSV-2 and antiproliferative effects on human cancer cell lines.…”

Purification and characterization of a thermostable mycelial lectin from basidiomycete Lentinus squarrosulus

“…The distribution of lectins is ubiquitous in nature and they perform different roles in variety of organisms including viruses, bacteria, fungi, yeast, algae, protozoa, animal and plant cells (Singh et al 1999). These are undoubtedly the most versatile group of proteins used in biological and biomedical research (Singh et al 2010a). Endogenous lectins in animals are known to mediate various biological recognition mechanisms, while plant lectins mainly serve as storage proteins or confer bactericidal properties to plants (Sobti et al 1999).…”

“…Of all the mushroom proteins, lectins are probably the most extensively investigated. There is an ever increasing interest in mushroom lectins due to their unique carbohydrate-binding specificities (Singh et al 2010a). In mushrooms, lectins are present in the caps, stipes, spores and mycelia (Zhang et al 2009).…”