4Z8B

crystal structure of a DGL mutant - H51G H131N

Summary for 4Z8B

• Entry DOI: 10.2210/pdb4z8b/pdb
• Descriptor: Lectin alpha chain, CALCIUM ION, MANGANESE (II) ION, ... (7 entities in total)
• Functional Keywords: lectin, dioclea grandiflora, h31a-h151n mutant, sugar binding protein
• Biological source: Dioclea grandiflora (Mucana)
• Total number of polymer chains: 1
• Total formula weight: 26314.10

Authors

Zamora-Caballero, S.,Perez, A.,Sanz, L.,Bravo, J.,Calvete, J.J. (deposition date: 2015-04-08, release date: 2015-07-22, Last modification date: 2024-01-10)

Primary citation

Zamora-Caballero, S.,Perez, A.,Sanz, L.,Bravo, J.,Calvete, J.J.
Quaternary structure of Dioclea grandiflora lectin assessed by equilibrium sedimentation and crystallographic analysis of recombinant mutants.
Febs Lett., 589:2290-2296, 2015

PubMed Abstract: The structural basis of the pH dependency of the dimer-tetramer transition exhibited by Brinda's type II Diocleinae lectins was investigated by equilibrium sedimentation and X-ray crystal structure determination of recombinant wild-type and site-directed single and double mutants of the pH-stable tetrameric Dioclea grandiflora lectin (r-αDGL). Releasing the peripheral site interdimeric contact between R60 and D78 rendered a mutant displaying dimer-tetramer equilibrium in the pH range equivalent to pKa±1 of the γ-COOH. Mutation of both histidines 51 and 131, but not the mutation of each His separately, abolished the formation of the Diocleinae canonical tetramer in the pH range 2.5-8.5. The X-ray structure of the double mutant r-αDGL H51G/H131N suggests that H131 plays a crucial role in networking loop 114-125 residues from all four subunits at the central cavity of the tetrameric lectin, and that H51 maintains the central cavity loops in a proper spatial orientation to make H131-mediated interdimer contacts.

PubMed: 26226421
DOI: 10.1016/j.febslet.2015.07.020

Experimental method

X-RAY DIFFRACTION (1.951 Å)