1Q8V: Pterocarpus Angolensis Lectin (Pal) In Complex With The Trimannoside [man(Alpha1-3)]man(Alpha1-6)man

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.
PDB ID: 1Q8VDownload
MMDB ID: 26484
PDB Deposition Date: 2003/8/22
Updated in MMDB: 2012/11
Experimental Method:
x-ray diffraction
Resolution: 1.85  Å
Source Organism:
Similar Structures:
Biological Unit for 1Q8V: dimeric; determined by author
Molecular Components in 1Q8V
Label Count Molecule
Proteins (2 molecules)
Molecule annotation
Chemicals (9 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB