Journal:Acta Cryst F:S2053230X25003905

Crystal structure of a recombinant mushroom Agaricus bisporus mannose-binding protein with a longer C-terminal region

Dr Hiromi Yoshida ^[1]

Molecular Tour
Agaricus bisporus mannose-binding protein (Abmb, 150 residues) is a ricin B-like type lectin, which has a beta-trefoil fold. Previously reported recombinant C-terminal His-tagged Abmb (additional 12 residues + 6 x His-tag, Abmb168h) showed specific binding activity to mannose and mannitol in surface plasmon resonance analysis. The structure of a recombinant Abmb including additional six residues at the C-terminus after cleavage by TEV protease (Abmb156, PDB code: 5eha) has been reported, however, carbohydrate binding site of Abmb has not yet been determined. The present structure of a recombinant Abmb with a longer C-terminal region (14 residues + 6 x His-tag, Abmb170h, crystalized in two forms, orthorhombic (PDB code: 9udy) and monoclinic (PDB code: 9ucz) showed high flexibility of several surface loop regions including C-terminal tail. This recombinant Abmb170h did not show binding affinity toward alpha-D-mannose but showed weak binding affinity toward GalNAc and beta-D-galactose in glycan search assay. The structure of Abmb170h reveals that the C-terminal region has an impact on the sugar binding and would be important to the mannose binding affinity. References

1. ↑ Yoshida H, Nakakita SI, Rachmawati H, Tjandrawinata RR, Ismaya WT. Crystal structure of a recombinant Agaricus bisporus mushroom mannose-binding protein with a longer C-terminal region. Acta Crystallogr F Struct Biol Commun. 2025 Jun 1. PMID:40349189 doi:10.1107/S2053230X25003905