1q8s
Pterocarpus angolensis lectin (PAL) in complex with the dimannoside Man(alpha1-6)Man
OverviewOverview
The crystal structure of a Man/Glc-specific lectin from the seeds of the bloodwood tree (Pterocarpus angolensis), a leguminous plant from central Africa, has been determined in complex with mannose and five manno-oligosaccharides. The lectin contains a classical mannose-specificity loop, but its metal-binding loop resembles that of lectins of unrelated specificity from Ulex europaeus and Maackia amurensis. As a consequence, the interactions with mannose in the primary binding site are conserved, but details of carbohydrate-binding outside the primary binding site differ from those seen in the equivalent carbohydrate complexes of concanavalin A. These observations explain the differences in their respective fine specificity profiles for oligomannoses. While Man(alpha1-3)Man and Man(alpha1-3)[Man(alpha1-6)]Man bind to PAL in low-energy conformations identical with that of ConA, Man(alpha1-6)Man is required to adopt a different conformation. Man(alpha1-2)Man can bind only in a single binding mode, in sharp contrast to ConA, which creates a higher affinity for this disaccharide by allowing two binding modes.
About this StructureAbout this Structure
1Q8S is a Single protein structure of sequence from Pterocarpus angolensis. Full crystallographic information is available from OCA.
ReferenceReference
Structural basis of oligomannose recognition by the Pterocarpus angolensis seed lectin., Loris R, Van Walle I, De Greve H, Beeckmans S, Deboeck F, Wyns L, Bouckaert J, J Mol Biol. 2004 Jan 30;335(5):1227-40. PMID:14729339 Page seeded by OCA on Sat May 3 06:00:28 2008