1BUU

ONE HO3+ FORM OF RAT MANNOSE-BINDING PROTEIN A

Summary for 1BUU

• Entry DOI: 10.2210/pdb1buu/pdb
• Descriptor: PROTEIN (MANNOSE-BINDING PROTEIN A), HOLMIUM ATOM (3 entities in total)
• Functional Keywords: lectin, host defense, metalloprotein, sugar binding protein
• Biological source: Rattus norvegicus (Norway rat)
• Total number of polymer chains: 1
• Total formula weight: 18614.75

Authors

Ng, K.K.-S.,Park-Snyder, S.,Weis, W.I. (deposition date: 1998-09-06, release date: 1998-09-09, Last modification date: 2024-10-30)

Primary citation

Ng, K.K.,Park-Snyder, S.,Weis, W.I.
Ca2+-dependent structural changes in C-type mannose-binding proteins.
Biochemistry, 37:17965-17976, 1998

PubMed Abstract: C-type animal lectins are a diverse family of proteins which mediate cell-surface carbohydrate-recognition events through a conserved carbohydrate-recognition domain (CRD). Most members of this family possess a carbohydrate-binding activity that depends strictly on the binding of Ca2+ at two sites, designated 1 and 2, in the CRD. The structural transitions associated with Ca2+ binding in C-type lectins have been investigated by determining high-resolution crystal structures of rat serum mannose-binding protein (MBP) bound to one Ho3+ in place of Ca2+, and the apo form of rat liver MBP. The removal of Ca2+ does not affect the core structure of the CRD, but dramatic conformational changes occur in the loops. The most significant structural change in the absence of Ca2+ is the isomerization of a cis-peptide bond preceding a conserved proline residue in Ca2+ site 2. This bond adopts the cis conformation in all Ca2+-bound structures, whereas both cis and trans conformations are observed in the absence of Ca2+. The pattern of structural changes in the three loops that interact with Ca2+ is dictated in large part by the conformation of the prolyl peptide bond. The highly conserved nature of Ca2+ site 2 suggests that the transitions observed in MBPs are general features of Ca2+ binding in C-type lectins.

PubMed: 9922165
DOI: 10.1021/bi981972a

Experimental method

X-RAY DIFFRACTION (1.9 Å)