Structural basis for both pro- and anti-inflammatory response induced by mannose-specific legume lectin from Cymbosema roseum

Abstract

Legume lectins, despite high sequence homology, express diverse biological activities that vary in potency and efficacy. In studies reported here, the mannose-specific lectin from Cymbosema roseum (CRLI), which binds N-glycoproteins, shows both pro-inflammatory effects when administered by local injection and anti-inflammatory effects when by systemic injection. Protein sequencing was obtained by Tandem Mass Spectrometry and the crystal structure was solved by X-ray crystallography using a Synchrotron radiation source. Molecular replacement and refinement were performed using CCP4 and the carbohydrate binding properties were described by affinity assays and computational docking. Biological assays were performed in order to evaluate the lectin edematogenic activity. The crystal structure of CRLI was established to a 1.8Å resolution in order to determine a structural basis for these differing activities. The structure of CRLI is closely homologous to those of other legume lectins at the monomer level and assembles into tetramers as do many of its homologues. The CRLI carbohydrate binding site was predicted by docking with a specific inhibitory trisaccharide. CRLI possesses a hydrophobic pocket for the binding of α-aminobutyric acid and that pocket is occupied in this structure as are the binding sites for calcium and manganese cations characteristic of legume lectins. CRLI route-dependent effects for acute inflammation are related to its carbohydrate binding domain (due to inhibition caused by the presence of α-methyl-mannoside), and are based on comparative analysis with ConA crystal structure. This may be due to carbohydrate binding site design, which differs at Tyr12 and Glu205 position.

Structural Studies of an Anti-Inflammatory Lectin from Canavalia boliviana Seeds in Complex with Dimannosides

“…Some Phaseoleae lectins, isolated from Canavalia grandiflora , C. ensiformis [56], Dioclea rostrata [ 55 ], C. brasiliensis , C. gladiata , C. maritima (Assreuy et al ., 2009) and Cymbosema roseum [57], elicit inflammatory responses that could be reversed by specific carbohydrates. Cymbosema roseum is also known to elicit anti-inflammatory responses after systemic administration, which has been described as a legume lectin pattern of action; an inflammatory response based on administration route [57]. Cbol anti-inflammatory action is very consistent because describes anti-inflammatory responses through the i.v.…”

Molecular Modeling of Lectin-Like Protein fromAcacia farnesianaReveals a Possible Anti-Inflammatory Mechanism in Carrageenan-Induced Inflammation

“…It has also been shown that legume lectins can be proinflammatory when administrated subcutaneously or anti-inflammatory when this administration is intravenous [20]. Alencar and coworkers [39] demonstrated that legume lectins act in inflammatory process via carbohydrate recognition domain (CDR), but AFAL is also capable of acting in a different way based on its affinity by CGN.…”

“…This sulfated polysaccharide has been used to test inflammation and anti-inflammatory activity with lectins for long time, but little can be deduced about how this activity occurs [41–43]. Some authors assumed that some anti-inflammatory events, such as inhibition of neutrophil migration, occur through competition for binding to neutrophils between lectins tested and selectins [20, 39], but AFAL also can inhibit the signaling pathway triggered by CGN through the recognition and binding, preventing the recognition of carrageenan by epithelial cells and inhibiting the induction of IL-8 production resulted from the activation of BCL10 [23, 25]. …”

“…The conformation of these loops is determined by the presence of calcium and transition metal ions coordinated in the protein structure [17–19]. One of the most studied biological activities of lectins is the ability to reduce the effects of inflammation caused by certain phlogistic agents, such as carrageenan (CGN) [20]. Many molecules with this ability were considered for their potential for the development of drugs with anti-inflammatory action [21].…”

Holothuria grisea agglutinin (HGA): the first invertebrate lectin with anti‐inflammatory effects

“…A considerable number of marine invertebrate lectins have already been purified and characterized, and considerable attention is focused on its biological recognition role [8][9][10][11][12]. The Table I summarizes the origin, specificity, and biological activity from some lectins [5,[17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. Then, they come as ancestral molecules that show a high degree of conservation during the evolution to superior vertebrates [13][14][15][16].…”